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postgresql/src/backend/utils/adt/jsonfuncs.c

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/*-------------------------------------------------------------------------
*
* jsonfuncs.c
* Functions to process JSON data types.
*
* Portions Copyright (c) 1996-2019, PostgreSQL Global Development Group
* Portions Copyright (c) 1994, Regents of the University of California
*
* IDENTIFICATION
* src/backend/utils/adt/jsonfuncs.c
*
*-------------------------------------------------------------------------
*/
#include "postgres.h"
#include <limits.h>
#include "access/htup_details.h"
#include "catalog/pg_type.h"
#include "fmgr.h"
#include "funcapi.h"
#include "lib/stringinfo.h"
#include "mb/pg_wchar.h"
#include "miscadmin.h"
#include "utils/array.h"
#include "utils/builtins.h"
#include "utils/hsearch.h"
#include "utils/json.h"
#include "utils/jsonapi.h"
#include "utils/jsonb.h"
#include "utils/lsyscache.h"
#include "utils/memutils.h"
#include "utils/syscache.h"
#include "utils/typcache.h"
/* Operations available for setPath */
#define JB_PATH_CREATE 0x0001
#define JB_PATH_DELETE 0x0002
#define JB_PATH_REPLACE 0x0004
#define JB_PATH_INSERT_BEFORE 0x0008
#define JB_PATH_INSERT_AFTER 0x0010
#define JB_PATH_CREATE_OR_INSERT \
(JB_PATH_INSERT_BEFORE | JB_PATH_INSERT_AFTER | JB_PATH_CREATE)
/* state for json_object_keys */
typedef struct OkeysState
{
JsonLexContext *lex;
char **result;
int result_size;
int result_count;
int sent_count;
} OkeysState;
/* state for iterate_json_values function */
typedef struct IterateJsonStringValuesState
{
JsonLexContext *lex;
JsonIterateStringValuesAction action; /* an action that will be applied
* to each json value */
void *action_state; /* any necessary context for iteration */
uint32 flags; /* what kind of elements from a json we want
* to iterate */
} IterateJsonStringValuesState;
/* state for transform_json_string_values function */
typedef struct TransformJsonStringValuesState
{
JsonLexContext *lex;
StringInfo strval; /* resulting json */
JsonTransformStringValuesAction action; /* an action that will be applied
* to each json value */
void *action_state; /* any necessary context for transformation */
} TransformJsonStringValuesState;
/* state for json_get* functions */
typedef struct GetState
{
JsonLexContext *lex;
text *tresult;
char *result_start;
bool normalize_results;
bool next_scalar;
int npath; /* length of each path-related array */
char **path_names; /* field name(s) being sought */
int *path_indexes; /* array index(es) being sought */
bool *pathok; /* is path matched to current depth? */
int *array_cur_index; /* current element index at each path
* level */
} GetState;
/* state for json_array_length */
typedef struct AlenState
{
JsonLexContext *lex;
int count;
} AlenState;
/* state for json_each */
typedef struct EachState
{
JsonLexContext *lex;
Tuplestorestate *tuple_store;
TupleDesc ret_tdesc;
MemoryContext tmp_cxt;
char *result_start;
bool normalize_results;
bool next_scalar;
char *normalized_scalar;
} EachState;
/* state for json_array_elements */
typedef struct ElementsState
{
JsonLexContext *lex;
const char *function_name;
Tuplestorestate *tuple_store;
TupleDesc ret_tdesc;
MemoryContext tmp_cxt;
char *result_start;
bool normalize_results;
bool next_scalar;
char *normalized_scalar;
} ElementsState;
/* state for get_json_object_as_hash */
typedef struct JHashState
{
JsonLexContext *lex;
const char *function_name;
HTAB *hash;
char *saved_scalar;
char *save_json_start;
JsonTokenType saved_token_type;
} JHashState;
/* hashtable element */
typedef struct JsonHashEntry
{
char fname[NAMEDATALEN]; /* hash key (MUST BE FIRST) */
char *val;
JsonTokenType type;
} JsonHashEntry;
/* structure to cache type I/O metadata needed for populate_scalar() */
typedef struct ScalarIOData
{
Oid typioparam;
FmgrInfo typiofunc;
} ScalarIOData;
/* these two structures are used recursively */
typedef struct ColumnIOData ColumnIOData;
typedef struct RecordIOData RecordIOData;
/* structure to cache metadata needed for populate_array() */
typedef struct ArrayIOData
{
ColumnIOData *element_info; /* metadata cache */
Oid element_type; /* array element type id */
int32 element_typmod; /* array element type modifier */
} ArrayIOData;
/* structure to cache metadata needed for populate_composite() */
typedef struct CompositeIOData
{
/*
* We use pointer to a RecordIOData here because variable-length struct
* RecordIOData can't be used directly in ColumnIOData.io union
*/
RecordIOData *record_io; /* metadata cache for populate_record() */
TupleDesc tupdesc; /* cached tuple descriptor */
/* these fields differ from target type only if domain over composite: */
Oid base_typid; /* base type id */
int32 base_typmod; /* base type modifier */
/* this field is used only if target type is domain over composite: */
void *domain_info; /* opaque cache for domain checks */
} CompositeIOData;
/* structure to cache metadata needed for populate_domain() */
typedef struct DomainIOData
{
ColumnIOData *base_io; /* metadata cache */
Oid base_typid; /* base type id */
int32 base_typmod; /* base type modifier */
void *domain_info; /* opaque cache for domain checks */
} DomainIOData;
/* enumeration type categories */
typedef enum TypeCat
{
TYPECAT_SCALAR = 's',
TYPECAT_ARRAY = 'a',
TYPECAT_COMPOSITE = 'c',
TYPECAT_COMPOSITE_DOMAIN = 'C',
TYPECAT_DOMAIN = 'd'
} TypeCat;
/* these two are stolen from hstore / record_out, used in populate_record* */
/* structure to cache record metadata needed for populate_record_field() */
struct ColumnIOData
{
Oid typid; /* column type id */
int32 typmod; /* column type modifier */
TypeCat typcat; /* column type category */
ScalarIOData scalar_io; /* metadata cache for directi conversion
* through input function */
union
{
ArrayIOData array;
CompositeIOData composite;
DomainIOData domain;
} io; /* metadata cache for various column type
* categories */
};
/* structure to cache record metadata needed for populate_record() */
struct RecordIOData
{
Oid record_type;
int32 record_typmod;
int ncolumns;
ColumnIOData columns[FLEXIBLE_ARRAY_MEMBER];
};
/* per-query cache for populate_recordset */
typedef struct PopulateRecordsetCache
{
Oid argtype; /* declared type of the record argument */
ColumnIOData c; /* metadata cache for populate_composite() */
MemoryContext fn_mcxt; /* where this is stored */
} PopulateRecordsetCache;
/* per-call state for populate_recordset */
typedef struct PopulateRecordsetState
{
JsonLexContext *lex;
const char *function_name;
HTAB *json_hash;
char *saved_scalar;
char *save_json_start;
JsonTokenType saved_token_type;
Tuplestorestate *tuple_store;
HeapTupleHeader rec;
PopulateRecordsetCache *cache;
} PopulateRecordsetState;
/* structure to cache metadata needed for populate_record_worker() */
typedef struct PopulateRecordCache
{
Oid argtype; /* declared type of the record argument */
ColumnIOData c; /* metadata cache for populate_composite() */
} PopulateRecordCache;
/* common data for populate_array_json() and populate_array_dim_jsonb() */
typedef struct PopulateArrayContext
{
ArrayBuildState *astate; /* array build state */
ArrayIOData *aio; /* metadata cache */
MemoryContext acxt; /* array build memory context */
MemoryContext mcxt; /* cache memory context */
const char *colname; /* for diagnostics only */
int *dims; /* dimensions */
int *sizes; /* current dimension counters */
int ndims; /* number of dimensions */
} PopulateArrayContext;
/* state for populate_array_json() */
typedef struct PopulateArrayState
{
JsonLexContext *lex; /* json lexer */
PopulateArrayContext *ctx; /* context */
char *element_start; /* start of the current array element */
char *element_scalar; /* current array element token if it is a
* scalar */
JsonTokenType element_type; /* current array element type */
} PopulateArrayState;
/* state for json_strip_nulls */
typedef struct StripnullState
{
JsonLexContext *lex;
StringInfo strval;
bool skip_next_null;
} StripnullState;
/* structure for generalized json/jsonb value passing */
typedef struct JsValue
{
bool is_json; /* json/jsonb */
union
{
struct
{
char *str; /* json string */
int len; /* json string length or -1 if null-terminated */
JsonTokenType type; /* json type */
} json; /* json value */
JsonbValue *jsonb; /* jsonb value */
} val;
} JsValue;
typedef struct JsObject
{
bool is_json; /* json/jsonb */
union
{
HTAB *json_hash;
JsonbContainer *jsonb_cont;
} val;
} JsObject;
/* useful macros for testing JsValue properties */
#define JsValueIsNull(jsv) \
((jsv)->is_json ? \
(!(jsv)->val.json.str || (jsv)->val.json.type == JSON_TOKEN_NULL) : \
(!(jsv)->val.jsonb || (jsv)->val.jsonb->type == jbvNull))
#define JsValueIsString(jsv) \
((jsv)->is_json ? (jsv)->val.json.type == JSON_TOKEN_STRING \
: ((jsv)->val.jsonb && (jsv)->val.jsonb->type == jbvString))
#define JsObjectIsEmpty(jso) \
((jso)->is_json \
? hash_get_num_entries((jso)->val.json_hash) == 0 \
: ((jso)->val.jsonb_cont == NULL || \
JsonContainerSize((jso)->val.jsonb_cont) == 0))
#define JsObjectFree(jso) \
do { \
if ((jso)->is_json) \
hash_destroy((jso)->val.json_hash); \
} while (0)
/* semantic action functions for json_object_keys */
static void okeys_object_field_start(void *state, char *fname, bool isnull);
static void okeys_array_start(void *state);
static void okeys_scalar(void *state, char *token, JsonTokenType tokentype);
/* semantic action functions for json_get* functions */
static void get_object_start(void *state);
static void get_object_end(void *state);
static void get_object_field_start(void *state, char *fname, bool isnull);
static void get_object_field_end(void *state, char *fname, bool isnull);
static void get_array_start(void *state);
static void get_array_end(void *state);
static void get_array_element_start(void *state, bool isnull);
static void get_array_element_end(void *state, bool isnull);
static void get_scalar(void *state, char *token, JsonTokenType tokentype);
/* common worker function for json getter functions */
static Datum get_path_all(FunctionCallInfo fcinfo, bool as_text);
static text *get_worker(text *json, char **tpath, int *ipath, int npath,
bool normalize_results);
static Datum get_jsonb_path_all(FunctionCallInfo fcinfo, bool as_text);
/* semantic action functions for json_array_length */
static void alen_object_start(void *state);
static void alen_scalar(void *state, char *token, JsonTokenType tokentype);
static void alen_array_element_start(void *state, bool isnull);
/* common workers for json{b}_each* functions */
static Datum each_worker(FunctionCallInfo fcinfo, bool as_text);
static Datum each_worker_jsonb(FunctionCallInfo fcinfo, const char *funcname,
bool as_text);
/* semantic action functions for json_each */
static void each_object_field_start(void *state, char *fname, bool isnull);
static void each_object_field_end(void *state, char *fname, bool isnull);
static void each_array_start(void *state);
static void each_scalar(void *state, char *token, JsonTokenType tokentype);
/* common workers for json{b}_array_elements_* functions */
static Datum elements_worker(FunctionCallInfo fcinfo, const char *funcname,
bool as_text);
static Datum elements_worker_jsonb(FunctionCallInfo fcinfo, const char *funcname,
bool as_text);
/* semantic action functions for json_array_elements */
static void elements_object_start(void *state);
static void elements_array_element_start(void *state, bool isnull);
static void elements_array_element_end(void *state, bool isnull);
static void elements_scalar(void *state, char *token, JsonTokenType tokentype);
/* turn a json object into a hash table */
static HTAB *get_json_object_as_hash(char *json, int len, const char *funcname);
/* semantic actions for populate_array_json */
static void populate_array_object_start(void *_state);
static void populate_array_array_end(void *_state);
static void populate_array_element_start(void *_state, bool isnull);
static void populate_array_element_end(void *_state, bool isnull);
static void populate_array_scalar(void *_state, char *token, JsonTokenType tokentype);
/* semantic action functions for get_json_object_as_hash */
static void hash_object_field_start(void *state, char *fname, bool isnull);
static void hash_object_field_end(void *state, char *fname, bool isnull);
static void hash_array_start(void *state);
static void hash_scalar(void *state, char *token, JsonTokenType tokentype);
/* semantic action functions for populate_recordset */
static void populate_recordset_object_field_start(void *state, char *fname, bool isnull);
static void populate_recordset_object_field_end(void *state, char *fname, bool isnull);
static void populate_recordset_scalar(void *state, char *token, JsonTokenType tokentype);
static void populate_recordset_object_start(void *state);
static void populate_recordset_object_end(void *state);
static void populate_recordset_array_start(void *state);
static void populate_recordset_array_element_start(void *state, bool isnull);
/* semantic action functions for json_strip_nulls */
static void sn_object_start(void *state);
static void sn_object_end(void *state);
static void sn_array_start(void *state);
static void sn_array_end(void *state);
static void sn_object_field_start(void *state, char *fname, bool isnull);
static void sn_array_element_start(void *state, bool isnull);
static void sn_scalar(void *state, char *token, JsonTokenType tokentype);
/* worker functions for populate_record, to_record, populate_recordset and to_recordset */
static Datum populate_recordset_worker(FunctionCallInfo fcinfo, const char *funcname,
bool is_json, bool have_record_arg);
static Datum populate_record_worker(FunctionCallInfo fcinfo, const char *funcname,
bool is_json, bool have_record_arg);
/* helper functions for populate_record[set] */
static HeapTupleHeader populate_record(TupleDesc tupdesc, RecordIOData **record_p,
HeapTupleHeader defaultval, MemoryContext mcxt,
JsObject *obj);
static void JsValueToJsObject(JsValue *jsv, JsObject *jso);
static Datum populate_composite(CompositeIOData *io, Oid typid,
const char *colname, MemoryContext mcxt,
HeapTupleHeader defaultval, JsValue *jsv, bool isnull);
static Datum populate_scalar(ScalarIOData *io, Oid typid, int32 typmod, JsValue *jsv);
static void prepare_column_cache(ColumnIOData *column, Oid typid, int32 typmod,
MemoryContext mcxt, bool need_scalar);
static Datum populate_record_field(ColumnIOData *col, Oid typid, int32 typmod,
const char *colname, MemoryContext mcxt, Datum defaultval,
JsValue *jsv, bool *isnull);
static RecordIOData *allocate_record_info(MemoryContext mcxt, int ncolumns);
static bool JsObjectGetField(JsObject *obj, char *field, JsValue *jsv);
static void populate_recordset_record(PopulateRecordsetState *state, JsObject *obj);
static void populate_array_json(PopulateArrayContext *ctx, char *json, int len);
static void populate_array_dim_jsonb(PopulateArrayContext *ctx, JsonbValue *jbv,
int ndim);
static void populate_array_report_expected_array(PopulateArrayContext *ctx, int ndim);
static void populate_array_assign_ndims(PopulateArrayContext *ctx, int ndims);
static void populate_array_check_dimension(PopulateArrayContext *ctx, int ndim);
static void populate_array_element(PopulateArrayContext *ctx, int ndim, JsValue *jsv);
static Datum populate_array(ArrayIOData *aio, const char *colname,
MemoryContext mcxt, JsValue *jsv);
static Datum populate_domain(DomainIOData *io, Oid typid, const char *colname,
MemoryContext mcxt, JsValue *jsv, bool isnull);
/* Worker that takes care of common setup for us */
static JsonbValue *findJsonbValueFromContainerLen(JsonbContainer *container,
uint32 flags,
char *key,
uint32 keylen);
/* functions supporting jsonb_delete, jsonb_set and jsonb_concat */
static JsonbValue *IteratorConcat(JsonbIterator **it1, JsonbIterator **it2,
JsonbParseState **state);
static JsonbValue *setPath(JsonbIterator **it, Datum *path_elems,
bool *path_nulls, int path_len,
JsonbParseState **st, int level, Jsonb *newval,
int op_type);
static void setPathObject(JsonbIterator **it, Datum *path_elems,
bool *path_nulls, int path_len, JsonbParseState **st,
int level,
Jsonb *newval, uint32 npairs, int op_type);
static void setPathArray(JsonbIterator **it, Datum *path_elems,
bool *path_nulls, int path_len, JsonbParseState **st,
int level, Jsonb *newval, uint32 nelems, int op_type);
static void addJsonbToParseState(JsonbParseState **jbps, Jsonb *jb);
/* function supporting iterate_json_values */
static void iterate_values_scalar(void *state, char *token, JsonTokenType tokentype);
static void iterate_values_object_field_start(void *state, char *fname, bool isnull);
/* functions supporting transform_json_string_values */
static void transform_string_values_object_start(void *state);
static void transform_string_values_object_end(void *state);
static void transform_string_values_array_start(void *state);
static void transform_string_values_array_end(void *state);
static void transform_string_values_object_field_start(void *state, char *fname, bool isnull);
static void transform_string_values_array_element_start(void *state, bool isnull);
static void transform_string_values_scalar(void *state, char *token, JsonTokenType tokentype);
/*
* SQL function json_object_keys
*
* Returns the set of keys for the object argument.
*
* This SRF operates in value-per-call mode. It processes the
* object during the first call, and the keys are simply stashed
* in an array, whose size is expanded as necessary. This is probably
* safe enough for a list of keys of a single object, since they are
* limited in size to NAMEDATALEN and the number of keys is unlikely to
* be so huge that it has major memory implications.
*/
Datum
jsonb_object_keys(PG_FUNCTION_ARGS)
{
FuncCallContext *funcctx;
OkeysState *state;
int i;
if (SRF_IS_FIRSTCALL())
{
MemoryContext oldcontext;
Jsonb *jb = PG_GETARG_JSONB_P(0);
bool skipNested = false;
JsonbIterator *it;
JsonbValue v;
JsonbIteratorToken r;
if (JB_ROOT_IS_SCALAR(jb))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot call %s on a scalar",
"jsonb_object_keys")));
else if (JB_ROOT_IS_ARRAY(jb))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot call %s on an array",
"jsonb_object_keys")));
funcctx = SRF_FIRSTCALL_INIT();
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
state = palloc(sizeof(OkeysState));
state->result_size = JB_ROOT_COUNT(jb);
state->result_count = 0;
state->sent_count = 0;
state->result = palloc(state->result_size * sizeof(char *));
it = JsonbIteratorInit(&jb->root);
while ((r = JsonbIteratorNext(&it, &v, skipNested)) != WJB_DONE)
{
skipNested = true;
if (r == WJB_KEY)
{
char *cstr;
cstr = palloc(v.val.string.len + 1 * sizeof(char));
memcpy(cstr, v.val.string.val, v.val.string.len);
cstr[v.val.string.len] = '\0';
state->result[state->result_count++] = cstr;
}
}
MemoryContextSwitchTo(oldcontext);
funcctx->user_fctx = (void *) state;
}
funcctx = SRF_PERCALL_SETUP();
state = (OkeysState *) funcctx->user_fctx;
if (state->sent_count < state->result_count)
{
char *nxt = state->result[state->sent_count++];
SRF_RETURN_NEXT(funcctx, CStringGetTextDatum(nxt));
}
/* cleanup to reduce or eliminate memory leaks */
for (i = 0; i < state->result_count; i++)
pfree(state->result[i]);
pfree(state->result);
pfree(state);
SRF_RETURN_DONE(funcctx);
}
Datum
json_object_keys(PG_FUNCTION_ARGS)
{
FuncCallContext *funcctx;
OkeysState *state;
int i;
if (SRF_IS_FIRSTCALL())
{
text *json = PG_GETARG_TEXT_PP(0);
JsonLexContext *lex = makeJsonLexContext(json, true);
JsonSemAction *sem;
MemoryContext oldcontext;
funcctx = SRF_FIRSTCALL_INIT();
oldcontext = MemoryContextSwitchTo(funcctx->multi_call_memory_ctx);
state = palloc(sizeof(OkeysState));
sem = palloc0(sizeof(JsonSemAction));
state->lex = lex;
state->result_size = 256;
state->result_count = 0;
state->sent_count = 0;
state->result = palloc(256 * sizeof(char *));
sem->semstate = (void *) state;
sem->array_start = okeys_array_start;
sem->scalar = okeys_scalar;
sem->object_field_start = okeys_object_field_start;
/* remainder are all NULL, courtesy of palloc0 above */
pg_parse_json(lex, sem);
/* keys are now in state->result */
pfree(lex->strval->data);
pfree(lex->strval);
pfree(lex);
pfree(sem);
MemoryContextSwitchTo(oldcontext);
funcctx->user_fctx = (void *) state;
}
funcctx = SRF_PERCALL_SETUP();
state = (OkeysState *) funcctx->user_fctx;
if (state->sent_count < state->result_count)
{
char *nxt = state->result[state->sent_count++];
SRF_RETURN_NEXT(funcctx, CStringGetTextDatum(nxt));
}
/* cleanup to reduce or eliminate memory leaks */
for (i = 0; i < state->result_count; i++)
pfree(state->result[i]);
pfree(state->result);
pfree(state);
SRF_RETURN_DONE(funcctx);
}
static void
okeys_object_field_start(void *state, char *fname, bool isnull)
{
OkeysState *_state = (OkeysState *) state;
/* only collecting keys for the top level object */
if (_state->lex->lex_level != 1)
return;
/* enlarge result array if necessary */
if (_state->result_count >= _state->result_size)
{
_state->result_size *= 2;
_state->result = (char **)
repalloc(_state->result, sizeof(char *) * _state->result_size);
}
/* save a copy of the field name */
_state->result[_state->result_count++] = pstrdup(fname);
}
static void
okeys_array_start(void *state)
{
OkeysState *_state = (OkeysState *) state;
/* top level must be a json object */
if (_state->lex->lex_level == 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot call %s on an array",
"json_object_keys")));
}
static void
okeys_scalar(void *state, char *token, JsonTokenType tokentype)
{
OkeysState *_state = (OkeysState *) state;
/* top level must be a json object */
if (_state->lex->lex_level == 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot call %s on a scalar",
"json_object_keys")));
}
/*
* json and jsonb getter functions
* these implement the -> ->> #> and #>> operators
* and the json{b?}_extract_path*(json, text, ...) functions
*/
Datum
json_object_field(PG_FUNCTION_ARGS)
{
text *json = PG_GETARG_TEXT_PP(0);
text *fname = PG_GETARG_TEXT_PP(1);
char *fnamestr = text_to_cstring(fname);
text *result;
result = get_worker(json, &fnamestr, NULL, 1, false);
if (result != NULL)
PG_RETURN_TEXT_P(result);
else
PG_RETURN_NULL();
}
Datum
jsonb_object_field(PG_FUNCTION_ARGS)
{
Jsonb *jb = PG_GETARG_JSONB_P(0);
text *key = PG_GETARG_TEXT_PP(1);
JsonbValue *v;
if (!JB_ROOT_IS_OBJECT(jb))
PG_RETURN_NULL();
v = findJsonbValueFromContainerLen(&jb->root, JB_FOBJECT,
VARDATA_ANY(key),
VARSIZE_ANY_EXHDR(key));
if (v != NULL)
PG_RETURN_JSONB_P(JsonbValueToJsonb(v));
PG_RETURN_NULL();
}
Datum
json_object_field_text(PG_FUNCTION_ARGS)
{
text *json = PG_GETARG_TEXT_PP(0);
text *fname = PG_GETARG_TEXT_PP(1);
char *fnamestr = text_to_cstring(fname);
text *result;
result = get_worker(json, &fnamestr, NULL, 1, true);
if (result != NULL)
PG_RETURN_TEXT_P(result);
else
PG_RETURN_NULL();
}
Datum
jsonb_object_field_text(PG_FUNCTION_ARGS)
{
Jsonb *jb = PG_GETARG_JSONB_P(0);
text *key = PG_GETARG_TEXT_PP(1);
JsonbValue *v;
if (!JB_ROOT_IS_OBJECT(jb))
PG_RETURN_NULL();
v = findJsonbValueFromContainerLen(&jb->root, JB_FOBJECT,
VARDATA_ANY(key),
VARSIZE_ANY_EXHDR(key));
if (v != NULL)
{
text *result = NULL;
switch (v->type)
{
case jbvNull:
break;
case jbvBool:
result = cstring_to_text(v->val.boolean ? "true" : "false");
break;
case jbvString:
result = cstring_to_text_with_len(v->val.string.val, v->val.string.len);
break;
case jbvNumeric:
result = cstring_to_text(DatumGetCString(DirectFunctionCall1(numeric_out,
PointerGetDatum(v->val.numeric))));
break;
case jbvBinary:
{
StringInfo jtext = makeStringInfo();
(void) JsonbToCString(jtext, v->val.binary.data, -1);
result = cstring_to_text_with_len(jtext->data, jtext->len);
}
break;
default:
elog(ERROR, "unrecognized jsonb type: %d", (int) v->type);
}
if (result)
PG_RETURN_TEXT_P(result);
}
PG_RETURN_NULL();
}
Datum
json_array_element(PG_FUNCTION_ARGS)
{
text *json = PG_GETARG_TEXT_PP(0);
int element = PG_GETARG_INT32(1);
text *result;
result = get_worker(json, NULL, &element, 1, false);
if (result != NULL)
PG_RETURN_TEXT_P(result);
else
PG_RETURN_NULL();
}
Datum
jsonb_array_element(PG_FUNCTION_ARGS)
{
Jsonb *jb = PG_GETARG_JSONB_P(0);
int element = PG_GETARG_INT32(1);
JsonbValue *v;
if (!JB_ROOT_IS_ARRAY(jb))
PG_RETURN_NULL();
/* Handle negative subscript */
if (element < 0)
{
uint32 nelements = JB_ROOT_COUNT(jb);
if (-element > nelements)
PG_RETURN_NULL();
else
element += nelements;
}
v = getIthJsonbValueFromContainer(&jb->root, element);
if (v != NULL)
PG_RETURN_JSONB_P(JsonbValueToJsonb(v));
PG_RETURN_NULL();
}
Datum
json_array_element_text(PG_FUNCTION_ARGS)
{
text *json = PG_GETARG_TEXT_PP(0);
int element = PG_GETARG_INT32(1);
text *result;
result = get_worker(json, NULL, &element, 1, true);
if (result != NULL)
PG_RETURN_TEXT_P(result);
else
PG_RETURN_NULL();
}
Datum
jsonb_array_element_text(PG_FUNCTION_ARGS)
{
Jsonb *jb = PG_GETARG_JSONB_P(0);
int element = PG_GETARG_INT32(1);
JsonbValue *v;
if (!JB_ROOT_IS_ARRAY(jb))
PG_RETURN_NULL();
/* Handle negative subscript */
if (element < 0)
{
uint32 nelements = JB_ROOT_COUNT(jb);
if (-element > nelements)
PG_RETURN_NULL();
else
element += nelements;
}
v = getIthJsonbValueFromContainer(&jb->root, element);
if (v != NULL)
{
text *result = NULL;
switch (v->type)
{
case jbvNull:
break;
case jbvBool:
result = cstring_to_text(v->val.boolean ? "true" : "false");
break;
case jbvString:
result = cstring_to_text_with_len(v->val.string.val, v->val.string.len);
break;
case jbvNumeric:
result = cstring_to_text(DatumGetCString(DirectFunctionCall1(numeric_out,
PointerGetDatum(v->val.numeric))));
break;
case jbvBinary:
{
StringInfo jtext = makeStringInfo();
(void) JsonbToCString(jtext, v->val.binary.data, -1);
result = cstring_to_text_with_len(jtext->data, jtext->len);
}
break;
default:
elog(ERROR, "unrecognized jsonb type: %d", (int) v->type);
}
if (result)
PG_RETURN_TEXT_P(result);
}
PG_RETURN_NULL();
}
Datum
json_extract_path(PG_FUNCTION_ARGS)
{
return get_path_all(fcinfo, false);
}
Datum
json_extract_path_text(PG_FUNCTION_ARGS)
{
return get_path_all(fcinfo, true);
}
/*
* common routine for extract_path functions
*/
static Datum
get_path_all(FunctionCallInfo fcinfo, bool as_text)
{
text *json = PG_GETARG_TEXT_PP(0);
ArrayType *path = PG_GETARG_ARRAYTYPE_P(1);
text *result;
Datum *pathtext;
bool *pathnulls;
int npath;
char **tpath;
int *ipath;
int i;
/*
* If the array contains any null elements, return NULL, on the grounds
* that you'd have gotten NULL if any RHS value were NULL in a nested
* series of applications of the -> operator. (Note: because we also
* return NULL for error cases such as no-such-field, this is true
* regardless of the contents of the rest of the array.)
*/
if (array_contains_nulls(path))
PG_RETURN_NULL();
deconstruct_array(path, TEXTOID, -1, false, 'i',
&pathtext, &pathnulls, &npath);
tpath = palloc(npath * sizeof(char *));
ipath = palloc(npath * sizeof(int));
for (i = 0; i < npath; i++)
{
Assert(!pathnulls[i]);
tpath[i] = TextDatumGetCString(pathtext[i]);
/*
* we have no idea at this stage what structure the document is so
* just convert anything in the path that we can to an integer and set
* all the other integers to INT_MIN which will never match.
*/
if (*tpath[i] != '\0')
{
long ind;
char *endptr;
errno = 0;
ind = strtol(tpath[i], &endptr, 10);
if (*endptr == '\0' && errno == 0 && ind <= INT_MAX && ind >= INT_MIN)
ipath[i] = (int) ind;
else
ipath[i] = INT_MIN;
}
else
ipath[i] = INT_MIN;
}
result = get_worker(json, tpath, ipath, npath, as_text);
if (result != NULL)
PG_RETURN_TEXT_P(result);
else
PG_RETURN_NULL();
}
/*
* get_worker
*
* common worker for all the json getter functions
*
* json: JSON object (in text form)
* tpath[]: field name(s) to extract
* ipath[]: array index(es) (zero-based) to extract, accepts negatives
* npath: length of tpath[] and/or ipath[]
* normalize_results: true to de-escape string and null scalars
*
* tpath can be NULL, or any one tpath[] entry can be NULL, if an object
* field is not to be matched at that nesting level. Similarly, ipath can
* be NULL, or any one ipath[] entry can be INT_MIN if an array element is
* not to be matched at that nesting level (a json datum should never be
* large enough to have -INT_MIN elements due to MaxAllocSize restriction).
*/
static text *
get_worker(text *json,
char **tpath,
int *ipath,
int npath,
bool normalize_results)
{
JsonLexContext *lex = makeJsonLexContext(json, true);
JsonSemAction *sem = palloc0(sizeof(JsonSemAction));
GetState *state = palloc0(sizeof(GetState));
Assert(npath >= 0);
state->lex = lex;
/* is it "_as_text" variant? */
state->normalize_results = normalize_results;
state->npath = npath;
state->path_names = tpath;
state->path_indexes = ipath;
state->pathok = palloc0(sizeof(bool) * npath);
state->array_cur_index = palloc(sizeof(int) * npath);
if (npath > 0)
state->pathok[0] = true;
sem->semstate = (void *) state;
/*
* Not all variants need all the semantic routines. Only set the ones that
* are actually needed for maximum efficiency.
*/
sem->scalar = get_scalar;
if (npath == 0)
{
sem->object_start = get_object_start;
sem->object_end = get_object_end;
sem->array_start = get_array_start;
sem->array_end = get_array_end;
}
if (tpath != NULL)
{
sem->object_field_start = get_object_field_start;
sem->object_field_end = get_object_field_end;
}
if (ipath != NULL)
{
sem->array_start = get_array_start;
sem->array_element_start = get_array_element_start;
sem->array_element_end = get_array_element_end;
}
pg_parse_json(lex, sem);
return state->tresult;
}
static void
get_object_start(void *state)
{
GetState *_state = (GetState *) state;
int lex_level = _state->lex->lex_level;
if (lex_level == 0 && _state->npath == 0)
{
/*
* Special case: we should match the entire object. We only need this
* at outermost level because at nested levels the match will have
* been started by the outer field or array element callback.
*/
_state->result_start = _state->lex->token_start;
}
}
static void
get_object_end(void *state)
{
GetState *_state = (GetState *) state;
int lex_level = _state->lex->lex_level;
if (lex_level == 0 && _state->npath == 0)
{
/* Special case: return the entire object */
char *start = _state->result_start;
int len = _state->lex->prev_token_terminator - start;
_state->tresult = cstring_to_text_with_len(start, len);
}
}
static void
get_object_field_start(void *state, char *fname, bool isnull)
{
GetState *_state = (GetState *) state;
bool get_next = false;
int lex_level = _state->lex->lex_level;
if (lex_level <= _state->npath &&
_state->pathok[lex_level - 1] &&
_state->path_names != NULL &&
_state->path_names[lex_level - 1] != NULL &&
strcmp(fname, _state->path_names[lex_level - 1]) == 0)
{
if (lex_level < _state->npath)
{
/* if not at end of path just mark path ok */
_state->pathok[lex_level] = true;
}
else
{
/* end of path, so we want this value */
get_next = true;
}
}
if (get_next)
{
/* this object overrides any previous matching object */
_state->tresult = NULL;
_state->result_start = NULL;
if (_state->normalize_results &&
_state->lex->token_type == JSON_TOKEN_STRING)
{
/* for as_text variants, tell get_scalar to set it for us */
_state->next_scalar = true;
}
else
{
/* for non-as_text variants, just note the json starting point */
_state->result_start = _state->lex->token_start;
}
}
}
static void
get_object_field_end(void *state, char *fname, bool isnull)
{
GetState *_state = (GetState *) state;
bool get_last = false;
int lex_level = _state->lex->lex_level;
/* same tests as in get_object_field_start */
if (lex_level <= _state->npath &&
_state->pathok[lex_level - 1] &&
_state->path_names != NULL &&
_state->path_names[lex_level - 1] != NULL &&
strcmp(fname, _state->path_names[lex_level - 1]) == 0)
{
if (lex_level < _state->npath)
{
/* done with this field so reset pathok */
_state->pathok[lex_level] = false;
}
else
{
/* end of path, so we want this value */
get_last = true;
}
}
/* for as_text scalar case, our work is already done */
if (get_last && _state->result_start != NULL)
{
/*
* make a text object from the string from the previously noted json
* start up to the end of the previous token (the lexer is by now
* ahead of us on whatever came after what we're interested in).
*/
if (isnull && _state->normalize_results)
_state->tresult = (text *) NULL;
else
{
char *start = _state->result_start;
int len = _state->lex->prev_token_terminator - start;
_state->tresult = cstring_to_text_with_len(start, len);
}
/* this should be unnecessary but let's do it for cleanliness: */
_state->result_start = NULL;
}
}
static void
get_array_start(void *state)
{
GetState *_state = (GetState *) state;
int lex_level = _state->lex->lex_level;
if (lex_level < _state->npath)
{
/* Initialize counting of elements in this array */
_state->array_cur_index[lex_level] = -1;
/* INT_MIN value is reserved to represent invalid subscript */
if (_state->path_indexes[lex_level] < 0 &&
_state->path_indexes[lex_level] != INT_MIN)
{
/* Negative subscript -- convert to positive-wise subscript */
int nelements = json_count_array_elements(_state->lex);
if (-_state->path_indexes[lex_level] <= nelements)
_state->path_indexes[lex_level] += nelements;
}
}
else if (lex_level == 0 && _state->npath == 0)
{
/*
* Special case: we should match the entire array. We only need this
* at the outermost level because at nested levels the match will have
* been started by the outer field or array element callback.
*/
_state->result_start = _state->lex->token_start;
}
}
static void
get_array_end(void *state)
{
GetState *_state = (GetState *) state;
int lex_level = _state->lex->lex_level;
if (lex_level == 0 && _state->npath == 0)
{
/* Special case: return the entire array */
char *start = _state->result_start;
int len = _state->lex->prev_token_terminator - start;
_state->tresult = cstring_to_text_with_len(start, len);
}
}
static void
get_array_element_start(void *state, bool isnull)
{
GetState *_state = (GetState *) state;
bool get_next = false;
int lex_level = _state->lex->lex_level;
/* Update array element counter */
if (lex_level <= _state->npath)
_state->array_cur_index[lex_level - 1]++;
if (lex_level <= _state->npath &&
_state->pathok[lex_level - 1] &&
_state->path_indexes != NULL &&
_state->array_cur_index[lex_level - 1] == _state->path_indexes[lex_level - 1])
{
if (lex_level < _state->npath)
{
/* if not at end of path just mark path ok */
_state->pathok[lex_level] = true;
}
else
{
/* end of path, so we want this value */
get_next = true;
}
}
/* same logic as for objects */
if (get_next)
{
_state->tresult = NULL;
_state->result_start = NULL;
if (_state->normalize_results &&
_state->lex->token_type == JSON_TOKEN_STRING)
{
_state->next_scalar = true;
}
else
{
_state->result_start = _state->lex->token_start;
}
}
}
static void
get_array_element_end(void *state, bool isnull)
{
GetState *_state = (GetState *) state;
bool get_last = false;
int lex_level = _state->lex->lex_level;
/* same tests as in get_array_element_start */
if (lex_level <= _state->npath &&
_state->pathok[lex_level - 1] &&
_state->path_indexes != NULL &&
_state->array_cur_index[lex_level - 1] == _state->path_indexes[lex_level - 1])
{
if (lex_level < _state->npath)
{
/* done with this element so reset pathok */
_state->pathok[lex_level] = false;
}
else
{
/* end of path, so we want this value */
get_last = true;
}
}
/* same logic as for objects */
if (get_last && _state->result_start != NULL)
{
if (isnull && _state->normalize_results)
_state->tresult = (text *) NULL;
else
{
char *start = _state->result_start;
int len = _state->lex->prev_token_terminator - start;
_state->tresult = cstring_to_text_with_len(start, len);
}
_state->result_start = NULL;
}
}
static void
get_scalar(void *state, char *token, JsonTokenType tokentype)
{
GetState *_state = (GetState *) state;
int lex_level = _state->lex->lex_level;
/* Check for whole-object match */
if (lex_level == 0 && _state->npath == 0)
{
if (_state->normalize_results && tokentype == JSON_TOKEN_STRING)
{
/* we want the de-escaped string */
_state->next_scalar = true;
}
else if (_state->normalize_results && tokentype == JSON_TOKEN_NULL)
{
_state->tresult = (text *) NULL;
}
else
{
/*
* This is a bit hokey: we will suppress whitespace after the
* scalar token, but not whitespace before it. Probably not worth
* doing our own space-skipping to avoid that.
*/
char *start = _state->lex->input;
int len = _state->lex->prev_token_terminator - start;
_state->tresult = cstring_to_text_with_len(start, len);
}
}
if (_state->next_scalar)
{
/* a de-escaped text value is wanted, so supply it */
_state->tresult = cstring_to_text(token);
/* make sure the next call to get_scalar doesn't overwrite it */
_state->next_scalar = false;
}
}
Datum
jsonb_extract_path(PG_FUNCTION_ARGS)
{
return get_jsonb_path_all(fcinfo, false);
}
Datum
jsonb_extract_path_text(PG_FUNCTION_ARGS)
{
return get_jsonb_path_all(fcinfo, true);
}
static Datum
get_jsonb_path_all(FunctionCallInfo fcinfo, bool as_text)
{
Jsonb *jb = PG_GETARG_JSONB_P(0);
ArrayType *path = PG_GETARG_ARRAYTYPE_P(1);
Jsonb *res;
Datum *pathtext;
bool *pathnulls;
int npath;
int i;
bool have_object = false,
have_array = false;
JsonbValue *jbvp = NULL;
JsonbValue tv;
JsonbContainer *container;
/*
* If the array contains any null elements, return NULL, on the grounds
* that you'd have gotten NULL if any RHS value were NULL in a nested
* series of applications of the -> operator. (Note: because we also
* return NULL for error cases such as no-such-field, this is true
* regardless of the contents of the rest of the array.)
*/
if (array_contains_nulls(path))
PG_RETURN_NULL();
deconstruct_array(path, TEXTOID, -1, false, 'i',
&pathtext, &pathnulls, &npath);
/* Identify whether we have object, array, or scalar at top-level */
container = &jb->root;
if (JB_ROOT_IS_OBJECT(jb))
have_object = true;
else if (JB_ROOT_IS_ARRAY(jb) && !JB_ROOT_IS_SCALAR(jb))
have_array = true;
else
{
Assert(JB_ROOT_IS_ARRAY(jb) && JB_ROOT_IS_SCALAR(jb));
/* Extract the scalar value, if it is what we'll return */
if (npath <= 0)
jbvp = getIthJsonbValueFromContainer(container, 0);
}
/*
* If the array is empty, return the entire LHS object, on the grounds
* that we should do zero field or element extractions. For the
* non-scalar case we can just hand back the object without much work. For
* the scalar case, fall through and deal with the value below the loop.
* (This inconsistency arises because there's no easy way to generate a
* JsonbValue directly for root-level containers.)
*/
if (npath <= 0 && jbvp == NULL)
{
if (as_text)
{
PG_RETURN_TEXT_P(cstring_to_text(JsonbToCString(NULL,
container,
VARSIZE(jb))));
}
else
{
/* not text mode - just hand back the jsonb */
PG_RETURN_JSONB_P(jb);
}
}
for (i = 0; i < npath; i++)
{
if (have_object)
{
jbvp = findJsonbValueFromContainerLen(container,
JB_FOBJECT,
VARDATA(pathtext[i]),
VARSIZE(pathtext[i]) - VARHDRSZ);
}
else if (have_array)
{
long lindex;
uint32 index;
char *indextext = TextDatumGetCString(pathtext[i]);
char *endptr;
errno = 0;
lindex = strtol(indextext, &endptr, 10);
if (endptr == indextext || *endptr != '\0' || errno != 0 ||
lindex > INT_MAX || lindex < INT_MIN)
PG_RETURN_NULL();
if (lindex >= 0)
{
index = (uint32) lindex;
}
else
{
/* Handle negative subscript */
uint32 nelements;
/* Container must be array, but make sure */
if (!JsonContainerIsArray(container))
elog(ERROR, "not a jsonb array");
nelements = JsonContainerSize(container);
if (-lindex > nelements)
PG_RETURN_NULL();
else
index = nelements + lindex;
}
jbvp = getIthJsonbValueFromContainer(container, index);
}
else
{
/* scalar, extraction yields a null */
PG_RETURN_NULL();
}
if (jbvp == NULL)
PG_RETURN_NULL();
else if (i == npath - 1)
break;
if (jbvp->type == jbvBinary)
{
JsonbIterator *it = JsonbIteratorInit((JsonbContainer *) jbvp->val.binary.data);
JsonbIteratorToken r;
r = JsonbIteratorNext(&it, &tv, true);
container = (JsonbContainer *) jbvp->val.binary.data;
have_object = r == WJB_BEGIN_OBJECT;
have_array = r == WJB_BEGIN_ARRAY;
}
else
{
have_object = jbvp->type == jbvObject;
have_array = jbvp->type == jbvArray;
}
}
if (as_text)
{
/* special-case outputs for string and null values */
if (jbvp->type == jbvString)
PG_RETURN_TEXT_P(cstring_to_text_with_len(jbvp->val.string.val,
jbvp->val.string.len));
if (jbvp->type == jbvNull)
PG_RETURN_NULL();
}
res = JsonbValueToJsonb(jbvp);
if (as_text)
{
PG_RETURN_TEXT_P(cstring_to_text(JsonbToCString(NULL,
&res->root,
VARSIZE(res))));
}
else
{
/* not text mode - just hand back the jsonb */
PG_RETURN_JSONB_P(res);
}
}
/*
* SQL function json_array_length(json) -> int
*/
Datum
json_array_length(PG_FUNCTION_ARGS)
{
text *json = PG_GETARG_TEXT_PP(0);
AlenState *state;
JsonLexContext *lex;
JsonSemAction *sem;
lex = makeJsonLexContext(json, false);
state = palloc0(sizeof(AlenState));
sem = palloc0(sizeof(JsonSemAction));
/* palloc0 does this for us */
#if 0
state->count = 0;
#endif
state->lex = lex;
sem->semstate = (void *) state;
sem->object_start = alen_object_start;
sem->scalar = alen_scalar;
sem->array_element_start = alen_array_element_start;
pg_parse_json(lex, sem);
PG_RETURN_INT32(state->count);
}
Datum
jsonb_array_length(PG_FUNCTION_ARGS)
{
Jsonb *jb = PG_GETARG_JSONB_P(0);
if (JB_ROOT_IS_SCALAR(jb))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot get array length of a scalar")));
else if (!JB_ROOT_IS_ARRAY(jb))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot get array length of a non-array")));
PG_RETURN_INT32(JB_ROOT_COUNT(jb));
}
/*
* These next two checks ensure that the json is an array (since it can't be
* a scalar or an object).
*/
static void
alen_object_start(void *state)
{
AlenState *_state = (AlenState *) state;
/* json structure check */
if (_state->lex->lex_level == 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot get array length of a non-array")));
}
static void
alen_scalar(void *state, char *token, JsonTokenType tokentype)
{
AlenState *_state = (AlenState *) state;
/* json structure check */
if (_state->lex->lex_level == 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot get array length of a scalar")));
}
static void
alen_array_element_start(void *state, bool isnull)
{
AlenState *_state = (AlenState *) state;
/* just count up all the level 1 elements */
if (_state->lex->lex_level == 1)
_state->count++;
}
/*
* SQL function json_each and json_each_text
*
* decompose a json object into key value pairs.
*
* Unlike json_object_keys() these SRFs operate in materialize mode,
* stashing results into a Tuplestore object as they go.
* The construction of tuples is done using a temporary memory context
* that is cleared out after each tuple is built.
*/
Datum
json_each(PG_FUNCTION_ARGS)
{
return each_worker(fcinfo, false);
}
Datum
jsonb_each(PG_FUNCTION_ARGS)
{
return each_worker_jsonb(fcinfo, "jsonb_each", false);
}
Datum
json_each_text(PG_FUNCTION_ARGS)
{
return each_worker(fcinfo, true);
}
Datum
jsonb_each_text(PG_FUNCTION_ARGS)
{
return each_worker_jsonb(fcinfo, "jsonb_each_text", true);
}
static Datum
each_worker_jsonb(FunctionCallInfo fcinfo, const char *funcname, bool as_text)
{
Jsonb *jb = PG_GETARG_JSONB_P(0);
ReturnSetInfo *rsi;
Tuplestorestate *tuple_store;
TupleDesc tupdesc;
TupleDesc ret_tdesc;
MemoryContext old_cxt,
tmp_cxt;
bool skipNested = false;
JsonbIterator *it;
JsonbValue v;
JsonbIteratorToken r;
if (!JB_ROOT_IS_OBJECT(jb))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot call %s on a non-object",
funcname)));
rsi = (ReturnSetInfo *) fcinfo->resultinfo;
if (!rsi || !IsA(rsi, ReturnSetInfo) ||
(rsi->allowedModes & SFRM_Materialize) == 0 ||
rsi->expectedDesc == NULL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("set-valued function called in context that "
"cannot accept a set")));
rsi->returnMode = SFRM_Materialize;
if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("function returning record called in context "
"that cannot accept type record")));
old_cxt = MemoryContextSwitchTo(rsi->econtext->ecxt_per_query_memory);
ret_tdesc = CreateTupleDescCopy(tupdesc);
BlessTupleDesc(ret_tdesc);
tuple_store =
tuplestore_begin_heap(rsi->allowedModes & SFRM_Materialize_Random,
false, work_mem);
MemoryContextSwitchTo(old_cxt);
tmp_cxt = AllocSetContextCreate(CurrentMemoryContext,
"jsonb_each temporary cxt",
ALLOCSET_DEFAULT_SIZES);
it = JsonbIteratorInit(&jb->root);
while ((r = JsonbIteratorNext(&it, &v, skipNested)) != WJB_DONE)
{
skipNested = true;
if (r == WJB_KEY)
{
text *key;
HeapTuple tuple;
Datum values[2];
bool nulls[2] = {false, false};
/* Use the tmp context so we can clean up after each tuple is done */
old_cxt = MemoryContextSwitchTo(tmp_cxt);
key = cstring_to_text_with_len(v.val.string.val, v.val.string.len);
/*
* The next thing the iterator fetches should be the value, no
* matter what shape it is.
*/
r = JsonbIteratorNext(&it, &v, skipNested);
Assert(r != WJB_DONE);
values[0] = PointerGetDatum(key);
if (as_text)
{
if (v.type == jbvNull)
{
/* a json null is an sql null in text mode */
nulls[1] = true;
values[1] = (Datum) NULL;
}
else
{
text *sv;
if (v.type == jbvString)
{
/* In text mode, scalar strings should be dequoted */
sv = cstring_to_text_with_len(v.val.string.val, v.val.string.len);
}
else
{
/* Turn anything else into a json string */
StringInfo jtext = makeStringInfo();
Jsonb *jb = JsonbValueToJsonb(&v);
(void) JsonbToCString(jtext, &jb->root, 0);
sv = cstring_to_text_with_len(jtext->data, jtext->len);
}
values[1] = PointerGetDatum(sv);
}
}
else
{
/* Not in text mode, just return the Jsonb */
Jsonb *val = JsonbValueToJsonb(&v);
values[1] = PointerGetDatum(val);
}
tuple = heap_form_tuple(ret_tdesc, values, nulls);
tuplestore_puttuple(tuple_store, tuple);
/* clean up and switch back */
MemoryContextSwitchTo(old_cxt);
MemoryContextReset(tmp_cxt);
}
}
MemoryContextDelete(tmp_cxt);
rsi->setResult = tuple_store;
rsi->setDesc = ret_tdesc;
PG_RETURN_NULL();
}
static Datum
each_worker(FunctionCallInfo fcinfo, bool as_text)
{
text *json = PG_GETARG_TEXT_PP(0);
JsonLexContext *lex;
JsonSemAction *sem;
ReturnSetInfo *rsi;
MemoryContext old_cxt;
TupleDesc tupdesc;
EachState *state;
lex = makeJsonLexContext(json, true);
state = palloc0(sizeof(EachState));
sem = palloc0(sizeof(JsonSemAction));
rsi = (ReturnSetInfo *) fcinfo->resultinfo;
if (!rsi || !IsA(rsi, ReturnSetInfo) ||
(rsi->allowedModes & SFRM_Materialize) == 0 ||
rsi->expectedDesc == NULL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("set-valued function called in context that "
"cannot accept a set")));
rsi->returnMode = SFRM_Materialize;
(void) get_call_result_type(fcinfo, NULL, &tupdesc);
/* make these in a sufficiently long-lived memory context */
old_cxt = MemoryContextSwitchTo(rsi->econtext->ecxt_per_query_memory);
state->ret_tdesc = CreateTupleDescCopy(tupdesc);
BlessTupleDesc(state->ret_tdesc);
state->tuple_store =
tuplestore_begin_heap(rsi->allowedModes & SFRM_Materialize_Random,
false, work_mem);
MemoryContextSwitchTo(old_cxt);
sem->semstate = (void *) state;
sem->array_start = each_array_start;
sem->scalar = each_scalar;
sem->object_field_start = each_object_field_start;
sem->object_field_end = each_object_field_end;
state->normalize_results = as_text;
state->next_scalar = false;
state->lex = lex;
state->tmp_cxt = AllocSetContextCreate(CurrentMemoryContext,
"json_each temporary cxt",
ALLOCSET_DEFAULT_SIZES);
pg_parse_json(lex, sem);
MemoryContextDelete(state->tmp_cxt);
rsi->setResult = state->tuple_store;
rsi->setDesc = state->ret_tdesc;
PG_RETURN_NULL();
}
static void
each_object_field_start(void *state, char *fname, bool isnull)
{
EachState *_state = (EachState *) state;
/* save a pointer to where the value starts */
if (_state->lex->lex_level == 1)
{
/*
* next_scalar will be reset in the object_field_end handler, and
* since we know the value is a scalar there is no danger of it being
* on while recursing down the tree.
*/
if (_state->normalize_results && _state->lex->token_type == JSON_TOKEN_STRING)
_state->next_scalar = true;
else
_state->result_start = _state->lex->token_start;
}
}
static void
each_object_field_end(void *state, char *fname, bool isnull)
{
EachState *_state = (EachState *) state;
MemoryContext old_cxt;
int len;
text *val;
HeapTuple tuple;
Datum values[2];
bool nulls[2] = {false, false};
/* skip over nested objects */
if (_state->lex->lex_level != 1)
return;
/* use the tmp context so we can clean up after each tuple is done */
old_cxt = MemoryContextSwitchTo(_state->tmp_cxt);
values[0] = CStringGetTextDatum(fname);
if (isnull && _state->normalize_results)
{
nulls[1] = true;
values[1] = (Datum) 0;
}
else if (_state->next_scalar)
{
values[1] = CStringGetTextDatum(_state->normalized_scalar);
_state->next_scalar = false;
}
else
{
len = _state->lex->prev_token_terminator - _state->result_start;
val = cstring_to_text_with_len(_state->result_start, len);
values[1] = PointerGetDatum(val);
}
tuple = heap_form_tuple(_state->ret_tdesc, values, nulls);
tuplestore_puttuple(_state->tuple_store, tuple);
/* clean up and switch back */
MemoryContextSwitchTo(old_cxt);
MemoryContextReset(_state->tmp_cxt);
}
static void
each_array_start(void *state)
{
EachState *_state = (EachState *) state;
/* json structure check */
if (_state->lex->lex_level == 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot deconstruct an array as an object")));
}
static void
each_scalar(void *state, char *token, JsonTokenType tokentype)
{
EachState *_state = (EachState *) state;
/* json structure check */
if (_state->lex->lex_level == 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot deconstruct a scalar")));
/* supply de-escaped value if required */
if (_state->next_scalar)
_state->normalized_scalar = token;
}
/*
* SQL functions json_array_elements and json_array_elements_text
*
* get the elements from a json array
*
* a lot of this processing is similar to the json_each* functions
*/
Datum
jsonb_array_elements(PG_FUNCTION_ARGS)
{
return elements_worker_jsonb(fcinfo, "jsonb_array_elements", false);
}
Datum
jsonb_array_elements_text(PG_FUNCTION_ARGS)
{
return elements_worker_jsonb(fcinfo, "jsonb_array_elements_text", true);
}
static Datum
elements_worker_jsonb(FunctionCallInfo fcinfo, const char *funcname,
bool as_text)
{
Jsonb *jb = PG_GETARG_JSONB_P(0);
ReturnSetInfo *rsi;
Tuplestorestate *tuple_store;
TupleDesc tupdesc;
TupleDesc ret_tdesc;
MemoryContext old_cxt,
tmp_cxt;
bool skipNested = false;
JsonbIterator *it;
JsonbValue v;
JsonbIteratorToken r;
if (JB_ROOT_IS_SCALAR(jb))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot extract elements from a scalar")));
else if (!JB_ROOT_IS_ARRAY(jb))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot extract elements from an object")));
rsi = (ReturnSetInfo *) fcinfo->resultinfo;
if (!rsi || !IsA(rsi, ReturnSetInfo) ||
(rsi->allowedModes & SFRM_Materialize) == 0 ||
rsi->expectedDesc == NULL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("set-valued function called in context that "
"cannot accept a set")));
rsi->returnMode = SFRM_Materialize;
/* it's a simple type, so don't use get_call_result_type() */
tupdesc = rsi->expectedDesc;
old_cxt = MemoryContextSwitchTo(rsi->econtext->ecxt_per_query_memory);
ret_tdesc = CreateTupleDescCopy(tupdesc);
BlessTupleDesc(ret_tdesc);
tuple_store =
tuplestore_begin_heap(rsi->allowedModes & SFRM_Materialize_Random,
false, work_mem);
MemoryContextSwitchTo(old_cxt);
tmp_cxt = AllocSetContextCreate(CurrentMemoryContext,
"jsonb_array_elements temporary cxt",
ALLOCSET_DEFAULT_SIZES);
it = JsonbIteratorInit(&jb->root);
while ((r = JsonbIteratorNext(&it, &v, skipNested)) != WJB_DONE)
{
skipNested = true;
if (r == WJB_ELEM)
{
HeapTuple tuple;
Datum values[1];
bool nulls[1] = {false};
/* use the tmp context so we can clean up after each tuple is done */
old_cxt = MemoryContextSwitchTo(tmp_cxt);
if (!as_text)
{
Jsonb *val = JsonbValueToJsonb(&v);
values[0] = PointerGetDatum(val);
}
else
{
if (v.type == jbvNull)
{
/* a json null is an sql null in text mode */
nulls[0] = true;
values[0] = (Datum) NULL;
}
else
{
text *sv;
if (v.type == jbvString)
{
/* in text mode scalar strings should be dequoted */
sv = cstring_to_text_with_len(v.val.string.val, v.val.string.len);
}
else
{
/* turn anything else into a json string */
StringInfo jtext = makeStringInfo();
Jsonb *jb = JsonbValueToJsonb(&v);
(void) JsonbToCString(jtext, &jb->root, 0);
sv = cstring_to_text_with_len(jtext->data, jtext->len);
}
values[0] = PointerGetDatum(sv);
}
}
tuple = heap_form_tuple(ret_tdesc, values, nulls);
tuplestore_puttuple(tuple_store, tuple);
/* clean up and switch back */
MemoryContextSwitchTo(old_cxt);
MemoryContextReset(tmp_cxt);
}
}
MemoryContextDelete(tmp_cxt);
rsi->setResult = tuple_store;
rsi->setDesc = ret_tdesc;
PG_RETURN_NULL();
}
Datum
json_array_elements(PG_FUNCTION_ARGS)
{
return elements_worker(fcinfo, "json_array_elements", false);
}
Datum
json_array_elements_text(PG_FUNCTION_ARGS)
{
return elements_worker(fcinfo, "json_array_elements_text", true);
}
static Datum
elements_worker(FunctionCallInfo fcinfo, const char *funcname, bool as_text)
{
text *json = PG_GETARG_TEXT_PP(0);
/* elements only needs escaped strings when as_text */
JsonLexContext *lex = makeJsonLexContext(json, as_text);
JsonSemAction *sem;
ReturnSetInfo *rsi;
MemoryContext old_cxt;
TupleDesc tupdesc;
ElementsState *state;
state = palloc0(sizeof(ElementsState));
sem = palloc0(sizeof(JsonSemAction));
rsi = (ReturnSetInfo *) fcinfo->resultinfo;
if (!rsi || !IsA(rsi, ReturnSetInfo) ||
(rsi->allowedModes & SFRM_Materialize) == 0 ||
rsi->expectedDesc == NULL)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("set-valued function called in context that "
"cannot accept a set")));
rsi->returnMode = SFRM_Materialize;
/* it's a simple type, so don't use get_call_result_type() */
tupdesc = rsi->expectedDesc;
/* make these in a sufficiently long-lived memory context */
old_cxt = MemoryContextSwitchTo(rsi->econtext->ecxt_per_query_memory);
state->ret_tdesc = CreateTupleDescCopy(tupdesc);
BlessTupleDesc(state->ret_tdesc);
state->tuple_store =
tuplestore_begin_heap(rsi->allowedModes & SFRM_Materialize_Random,
false, work_mem);
MemoryContextSwitchTo(old_cxt);
sem->semstate = (void *) state;
sem->object_start = elements_object_start;
sem->scalar = elements_scalar;
sem->array_element_start = elements_array_element_start;
sem->array_element_end = elements_array_element_end;
state->function_name = funcname;
state->normalize_results = as_text;
state->next_scalar = false;
state->lex = lex;
state->tmp_cxt = AllocSetContextCreate(CurrentMemoryContext,
"json_array_elements temporary cxt",
ALLOCSET_DEFAULT_SIZES);
pg_parse_json(lex, sem);
MemoryContextDelete(state->tmp_cxt);
rsi->setResult = state->tuple_store;
rsi->setDesc = state->ret_tdesc;
PG_RETURN_NULL();
}
static void
elements_array_element_start(void *state, bool isnull)
{
ElementsState *_state = (ElementsState *) state;
/* save a pointer to where the value starts */
if (_state->lex->lex_level == 1)
{
/*
* next_scalar will be reset in the array_element_end handler, and
* since we know the value is a scalar there is no danger of it being
* on while recursing down the tree.
*/
if (_state->normalize_results && _state->lex->token_type == JSON_TOKEN_STRING)
_state->next_scalar = true;
else
_state->result_start = _state->lex->token_start;
}
}
static void
elements_array_element_end(void *state, bool isnull)
{
ElementsState *_state = (ElementsState *) state;
MemoryContext old_cxt;
int len;
text *val;
HeapTuple tuple;
Datum values[1];
bool nulls[1] = {false};
/* skip over nested objects */
if (_state->lex->lex_level != 1)
return;
/* use the tmp context so we can clean up after each tuple is done */
old_cxt = MemoryContextSwitchTo(_state->tmp_cxt);
if (isnull && _state->normalize_results)
{
nulls[0] = true;
values[0] = (Datum) NULL;
}
else if (_state->next_scalar)
{
values[0] = CStringGetTextDatum(_state->normalized_scalar);
_state->next_scalar = false;
}
else
{
len = _state->lex->prev_token_terminator - _state->result_start;
val = cstring_to_text_with_len(_state->result_start, len);
values[0] = PointerGetDatum(val);
}
tuple = heap_form_tuple(_state->ret_tdesc, values, nulls);
tuplestore_puttuple(_state->tuple_store, tuple);
/* clean up and switch back */
MemoryContextSwitchTo(old_cxt);
MemoryContextReset(_state->tmp_cxt);
}
static void
elements_object_start(void *state)
{
ElementsState *_state = (ElementsState *) state;
/* json structure check */
if (_state->lex->lex_level == 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot call %s on a non-array",
_state->function_name)));
}
static void
elements_scalar(void *state, char *token, JsonTokenType tokentype)
{
ElementsState *_state = (ElementsState *) state;
/* json structure check */
if (_state->lex->lex_level == 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot call %s on a scalar",
_state->function_name)));
/* supply de-escaped value if required */
if (_state->next_scalar)
_state->normalized_scalar = token;
}
/*
* SQL function json_populate_record
*
* set fields in a record from the argument json
*
* Code adapted shamelessly from hstore's populate_record
* which is in turn partly adapted from record_out.
*
* The json is decomposed into a hash table, in which each
* field in the record is then looked up by name. For jsonb
* we fetch the values direct from the object.
*/
Datum
jsonb_populate_record(PG_FUNCTION_ARGS)
{
return populate_record_worker(fcinfo, "jsonb_populate_record",
false, true);
}
Datum
jsonb_to_record(PG_FUNCTION_ARGS)
{
return populate_record_worker(fcinfo, "jsonb_to_record",
false, false);
}
Datum
json_populate_record(PG_FUNCTION_ARGS)
{
return populate_record_worker(fcinfo, "json_populate_record",
true, true);
}
Datum
json_to_record(PG_FUNCTION_ARGS)
{
return populate_record_worker(fcinfo, "json_to_record",
true, false);
}
/* helper function for diagnostics */
static void
populate_array_report_expected_array(PopulateArrayContext *ctx, int ndim)
{
if (ndim <= 0)
{
if (ctx->colname)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("expected JSON array"),
errhint("See the value of key \"%s\".", ctx->colname)));
else
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("expected JSON array")));
}
else
{
StringInfoData indices;
int i;
initStringInfo(&indices);
Assert(ctx->ndims > 0 && ndim < ctx->ndims);
for (i = 0; i < ndim; i++)
appendStringInfo(&indices, "[%d]", ctx->sizes[i]);
if (ctx->colname)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("expected JSON array"),
errhint("See the array element %s of key \"%s\".",
indices.data, ctx->colname)));
else
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("expected JSON array"),
errhint("See the array element %s.",
indices.data)));
}
}
/* set the number of dimensions of the populated array when it becomes known */
static void
populate_array_assign_ndims(PopulateArrayContext *ctx, int ndims)
{
int i;
Assert(ctx->ndims <= 0);
if (ndims <= 0)
populate_array_report_expected_array(ctx, ndims);
ctx->ndims = ndims;
ctx->dims = palloc(sizeof(int) * ndims);
ctx->sizes = palloc0(sizeof(int) * ndims);
for (i = 0; i < ndims; i++)
ctx->dims[i] = -1; /* dimensions are unknown yet */
}
/* check the populated subarray dimension */
static void
populate_array_check_dimension(PopulateArrayContext *ctx, int ndim)
{
int dim = ctx->sizes[ndim]; /* current dimension counter */
if (ctx->dims[ndim] == -1)
ctx->dims[ndim] = dim; /* assign dimension if not yet known */
else if (ctx->dims[ndim] != dim)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("malformed JSON array"),
errdetail("Multidimensional arrays must have "
"sub-arrays with matching dimensions.")));
/* reset the current array dimension size counter */
ctx->sizes[ndim] = 0;
/* increment the parent dimension counter if it is a nested sub-array */
if (ndim > 0)
ctx->sizes[ndim - 1]++;
}
static void
populate_array_element(PopulateArrayContext *ctx, int ndim, JsValue *jsv)
{
Datum element;
bool element_isnull;
/* populate the array element */
element = populate_record_field(ctx->aio->element_info,
ctx->aio->element_type,
ctx->aio->element_typmod,
NULL, ctx->mcxt, PointerGetDatum(NULL),
jsv, &element_isnull);
accumArrayResult(ctx->astate, element, element_isnull,
ctx->aio->element_type, ctx->acxt);
Assert(ndim > 0);
ctx->sizes[ndim - 1]++; /* increment current dimension counter */
}
/* json object start handler for populate_array_json() */
static void
populate_array_object_start(void *_state)
{
PopulateArrayState *state = (PopulateArrayState *) _state;
int ndim = state->lex->lex_level;
if (state->ctx->ndims <= 0)
populate_array_assign_ndims(state->ctx, ndim);
else if (ndim < state->ctx->ndims)
populate_array_report_expected_array(state->ctx, ndim);
}
/* json array end handler for populate_array_json() */
static void
populate_array_array_end(void *_state)
{
PopulateArrayState *state = (PopulateArrayState *) _state;
PopulateArrayContext *ctx = state->ctx;
int ndim = state->lex->lex_level;
if (ctx->ndims <= 0)
populate_array_assign_ndims(ctx, ndim + 1);
if (ndim < ctx->ndims)
populate_array_check_dimension(ctx, ndim);
}
/* json array element start handler for populate_array_json() */
static void
populate_array_element_start(void *_state, bool isnull)
{
PopulateArrayState *state = (PopulateArrayState *) _state;
int ndim = state->lex->lex_level;
if (state->ctx->ndims <= 0 || ndim == state->ctx->ndims)
{
/* remember current array element start */
state->element_start = state->lex->token_start;
state->element_type = state->lex->token_type;
state->element_scalar = NULL;
}
}
/* json array element end handler for populate_array_json() */
static void
populate_array_element_end(void *_state, bool isnull)
{
PopulateArrayState *state = (PopulateArrayState *) _state;
PopulateArrayContext *ctx = state->ctx;
int ndim = state->lex->lex_level;
Assert(ctx->ndims > 0);
if (ndim == ctx->ndims)
{
JsValue jsv;
jsv.is_json = true;
jsv.val.json.type = state->element_type;
if (isnull)
{
Assert(jsv.val.json.type == JSON_TOKEN_NULL);
jsv.val.json.str = NULL;
jsv.val.json.len = 0;
}
else if (state->element_scalar)
{
jsv.val.json.str = state->element_scalar;
jsv.val.json.len = -1; /* null-terminated */
}
else
{
jsv.val.json.str = state->element_start;
jsv.val.json.len = (state->lex->prev_token_terminator -
state->element_start) * sizeof(char);
}
populate_array_element(ctx, ndim, &jsv);
}
}
/* json scalar handler for populate_array_json() */
static void
populate_array_scalar(void *_state, char *token, JsonTokenType tokentype)
{
PopulateArrayState *state = (PopulateArrayState *) _state;
PopulateArrayContext *ctx = state->ctx;
int ndim = state->lex->lex_level;
if (ctx->ndims <= 0)
populate_array_assign_ndims(ctx, ndim);
else if (ndim < ctx->ndims)
populate_array_report_expected_array(ctx, ndim);
if (ndim == ctx->ndims)
{
/* remember the scalar element token */
state->element_scalar = token;
/* element_type must already be set in populate_array_element_start() */
Assert(state->element_type == tokentype);
}
}
/* parse a json array and populate array */
static void
populate_array_json(PopulateArrayContext *ctx, char *json, int len)
{
PopulateArrayState state;
JsonSemAction sem;
state.lex = makeJsonLexContextCstringLen(json, len, true);
state.ctx = ctx;
memset(&sem, 0, sizeof(sem));
sem.semstate = (void *) &state;
sem.object_start = populate_array_object_start;
sem.array_end = populate_array_array_end;
sem.array_element_start = populate_array_element_start;
sem.array_element_end = populate_array_element_end;
sem.scalar = populate_array_scalar;
pg_parse_json(state.lex, &sem);
/* number of dimensions should be already known */
Assert(ctx->ndims > 0 && ctx->dims);
pfree(state.lex);
}
/*
* populate_array_dim_jsonb() -- Iterate recursively through jsonb sub-array
* elements and accumulate result using given ArrayBuildState.
*/
static void
populate_array_dim_jsonb(PopulateArrayContext *ctx, /* context */
JsonbValue *jbv, /* jsonb sub-array */
int ndim) /* current dimension */
{
JsonbContainer *jbc = jbv->val.binary.data;
JsonbIterator *it;
JsonbIteratorToken tok;
JsonbValue val;
JsValue jsv;
check_stack_depth();
if (jbv->type != jbvBinary || !JsonContainerIsArray(jbc))
populate_array_report_expected_array(ctx, ndim - 1);
Assert(!JsonContainerIsScalar(jbc));
it = JsonbIteratorInit(jbc);
tok = JsonbIteratorNext(&it, &val, true);
Assert(tok == WJB_BEGIN_ARRAY);
tok = JsonbIteratorNext(&it, &val, true);
/*
* If the number of dimensions is not yet known and we have found end of
* the array, or the first child element is not an array, then assign the
* number of dimensions now.
*/
if (ctx->ndims <= 0 &&
(tok == WJB_END_ARRAY ||
(tok == WJB_ELEM &&
(val.type != jbvBinary ||
!JsonContainerIsArray(val.val.binary.data)))))
populate_array_assign_ndims(ctx, ndim);
jsv.is_json = false;
jsv.val.jsonb = &val;
/* process all the array elements */
while (tok == WJB_ELEM)
{
/*
* Recurse only if the dimensions of dimensions is still unknown or if
* it is not the innermost dimension.
*/
if (ctx->ndims > 0 && ndim >= ctx->ndims)
populate_array_element(ctx, ndim, &jsv);
else
{
/* populate child sub-array */
populate_array_dim_jsonb(ctx, &val, ndim + 1);
/* number of dimensions should be already known */
Assert(ctx->ndims > 0 && ctx->dims);
populate_array_check_dimension(ctx, ndim);
}
tok = JsonbIteratorNext(&it, &val, true);
}
Assert(tok == WJB_END_ARRAY);
/* free iterator, iterating until WJB_DONE */
tok = JsonbIteratorNext(&it, &val, true);
Assert(tok == WJB_DONE && !it);
}
/* recursively populate an array from json/jsonb */
static Datum
populate_array(ArrayIOData *aio,
const char *colname,
MemoryContext mcxt,
JsValue *jsv)
{
PopulateArrayContext ctx;
Datum result;
int *lbs;
int i;
ctx.aio = aio;
ctx.mcxt = mcxt;
ctx.acxt = CurrentMemoryContext;
ctx.astate = initArrayResult(aio->element_type, ctx.acxt, true);
ctx.colname = colname;
ctx.ndims = 0; /* unknown yet */
ctx.dims = NULL;
ctx.sizes = NULL;
if (jsv->is_json)
populate_array_json(&ctx, jsv->val.json.str,
jsv->val.json.len >= 0 ? jsv->val.json.len
: strlen(jsv->val.json.str));
else
{
populate_array_dim_jsonb(&ctx, jsv->val.jsonb, 1);
ctx.dims[0] = ctx.sizes[0];
}
Assert(ctx.ndims > 0);
lbs = palloc(sizeof(int) * ctx.ndims);
for (i = 0; i < ctx.ndims; i++)
lbs[i] = 1;
result = makeMdArrayResult(ctx.astate, ctx.ndims, ctx.dims, lbs,
ctx.acxt, true);
pfree(ctx.dims);
pfree(ctx.sizes);
pfree(lbs);
return result;
}
static void
JsValueToJsObject(JsValue *jsv, JsObject *jso)
{
jso->is_json = jsv->is_json;
if (jsv->is_json)
{
/* convert plain-text json into a hash table */
jso->val.json_hash =
get_json_object_as_hash(jsv->val.json.str,
jsv->val.json.len >= 0
? jsv->val.json.len
: strlen(jsv->val.json.str),
"populate_composite");
}
else
{
JsonbValue *jbv = jsv->val.jsonb;
if (jbv->type == jbvBinary &&
JsonContainerIsObject(jbv->val.binary.data))
{
jso->val.jsonb_cont = jbv->val.binary.data;
}
else
{
bool is_scalar;
is_scalar = IsAJsonbScalar(jbv) ||
(jbv->type == jbvBinary &&
JsonContainerIsScalar(jbv->val.binary.data));
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
is_scalar
? errmsg("cannot call %s on a scalar",
"populate_composite")
: errmsg("cannot call %s on an array",
"populate_composite")));
}
}
}
/* acquire or update cached tuple descriptor for a composite type */
static void
update_cached_tupdesc(CompositeIOData *io, MemoryContext mcxt)
{
if (!io->tupdesc ||
io->tupdesc->tdtypeid != io->base_typid ||
io->tupdesc->tdtypmod != io->base_typmod)
{
TupleDesc tupdesc = lookup_rowtype_tupdesc(io->base_typid,
io->base_typmod);
MemoryContext oldcxt;
if (io->tupdesc)
FreeTupleDesc(io->tupdesc);
/* copy tuple desc without constraints into cache memory context */
oldcxt = MemoryContextSwitchTo(mcxt);
io->tupdesc = CreateTupleDescCopy(tupdesc);
MemoryContextSwitchTo(oldcxt);
ReleaseTupleDesc(tupdesc);
}
}
/* recursively populate a composite (row type) value from json/jsonb */
static Datum
populate_composite(CompositeIOData *io,
Oid typid,
const char *colname,
MemoryContext mcxt,
HeapTupleHeader defaultval,
JsValue *jsv,
bool isnull)
{
Datum result;
/* acquire/update cached tuple descriptor */
update_cached_tupdesc(io, mcxt);
if (isnull)
result = (Datum) 0;
else
{
HeapTupleHeader tuple;
JsObject jso;
/* prepare input value */
JsValueToJsObject(jsv, &jso);
/* populate resulting record tuple */
tuple = populate_record(io->tupdesc, &io->record_io,
defaultval, mcxt, &jso);
result = HeapTupleHeaderGetDatum(tuple);
JsObjectFree(&jso);
}
/*
* If it's domain over composite, check domain constraints. (This should
* probably get refactored so that we can see the TYPECAT value, but for
* now, we can tell by comparing typid to base_typid.)
*/
if (typid != io->base_typid && typid != RECORDOID)
domain_check(result, isnull, typid, &io->domain_info, mcxt);
return result;
}
/* populate non-null scalar value from json/jsonb value */
static Datum
populate_scalar(ScalarIOData *io, Oid typid, int32 typmod, JsValue *jsv)
{
Datum res;
char *str = NULL;
char *json = NULL;
if (jsv->is_json)
{
int len = jsv->val.json.len;
json = jsv->val.json.str;
Assert(json);
if (len >= 0)
{
/* Need to copy non-null-terminated string */
str = palloc(len + 1 * sizeof(char));
memcpy(str, json, len);
str[len] = '\0';
}
else
str = json; /* string is already null-terminated */
/* If converting to json/jsonb, make string into valid JSON literal */
if ((typid == JSONOID || typid == JSONBOID) &&
jsv->val.json.type == JSON_TOKEN_STRING)
{
StringInfoData buf;
initStringInfo(&buf);
escape_json(&buf, str);
/* free temporary buffer */
if (str != json)
pfree(str);
str = buf.data;
}
}
else
{
JsonbValue *jbv = jsv->val.jsonb;
if (typid == JSONBOID)
{
Jsonb *jsonb = JsonbValueToJsonb(jbv); /* directly use jsonb */
return JsonbPGetDatum(jsonb);
}
/* convert jsonb to string for typio call */
else if (typid == JSONOID && jbv->type != jbvBinary)
{
/*
* Convert scalar jsonb (non-scalars are passed here as jbvBinary)
* to json string, preserving quotes around top-level strings.
*/
Jsonb *jsonb = JsonbValueToJsonb(jbv);
str = JsonbToCString(NULL, &jsonb->root, VARSIZE(jsonb));
}
else if (jbv->type == jbvString) /* quotes are stripped */
str = pnstrdup(jbv->val.string.val, jbv->val.string.len);
else if (jbv->type == jbvBool)
str = pstrdup(jbv->val.boolean ? "true" : "false");
else if (jbv->type == jbvNumeric)
str = DatumGetCString(DirectFunctionCall1(numeric_out,
PointerGetDatum(jbv->val.numeric)));
else if (jbv->type == jbvBinary)
str = JsonbToCString(NULL, jbv->val.binary.data,
jbv->val.binary.len);
else
elog(ERROR, "unrecognized jsonb type: %d", (int) jbv->type);
}
res = InputFunctionCall(&io->typiofunc, str, io->typioparam, typmod);
/* free temporary buffer */
if (str != json)
pfree(str);
return res;
}
static Datum
populate_domain(DomainIOData *io,
Oid typid,
const char *colname,
MemoryContext mcxt,
JsValue *jsv,
bool isnull)
{
Datum res;
if (isnull)
res = (Datum) 0;
else
{
res = populate_record_field(io->base_io,
io->base_typid, io->base_typmod,
colname, mcxt, PointerGetDatum(NULL),
jsv, &isnull);
Assert(!isnull);
}
domain_check(res, isnull, typid, &io->domain_info, mcxt);
return res;
}
/* prepare column metadata cache for the given type */
static void
prepare_column_cache(ColumnIOData *column,
Oid typid,
int32 typmod,
MemoryContext mcxt,
bool need_scalar)
{
HeapTuple tup;
Form_pg_type type;
column->typid = typid;
column->typmod = typmod;
tup = SearchSysCache1(TYPEOID, ObjectIdGetDatum(typid));
if (!HeapTupleIsValid(tup))
elog(ERROR, "cache lookup failed for type %u", typid);
type = (Form_pg_type) GETSTRUCT(tup);
if (type->typtype == TYPTYPE_DOMAIN)
{
/*
* We can move directly to the bottom base type; domain_check() will
* take care of checking all constraints for a stack of domains.
*/
Oid base_typid;
int32 base_typmod = typmod;
base_typid = getBaseTypeAndTypmod(typid, &base_typmod);
if (get_typtype(base_typid) == TYPTYPE_COMPOSITE)
{
/* domain over composite has its own code path */
column->typcat = TYPECAT_COMPOSITE_DOMAIN;
column->io.composite.record_io = NULL;
column->io.composite.tupdesc = NULL;
column->io.composite.base_typid = base_typid;
column->io.composite.base_typmod = base_typmod;
column->io.composite.domain_info = NULL;
}
else
{
/* domain over anything else */
column->typcat = TYPECAT_DOMAIN;
column->io.domain.base_typid = base_typid;
column->io.domain.base_typmod = base_typmod;
column->io.domain.base_io =
MemoryContextAllocZero(mcxt, sizeof(ColumnIOData));
column->io.domain.domain_info = NULL;
}
}
else if (type->typtype == TYPTYPE_COMPOSITE || typid == RECORDOID)
{
column->typcat = TYPECAT_COMPOSITE;
column->io.composite.record_io = NULL;
column->io.composite.tupdesc = NULL;
column->io.composite.base_typid = typid;
column->io.composite.base_typmod = typmod;
column->io.composite.domain_info = NULL;
}
else if (type->typlen == -1 && OidIsValid(type->typelem))
{
column->typcat = TYPECAT_ARRAY;
column->io.array.element_info = MemoryContextAllocZero(mcxt,
sizeof(ColumnIOData));
column->io.array.element_type = type->typelem;
/* array element typemod stored in attribute's typmod */
column->io.array.element_typmod = typmod;
}
else
{
column->typcat = TYPECAT_SCALAR;
need_scalar = true;
}
/* caller can force us to look up scalar_io info even for non-scalars */
if (need_scalar)
{
Oid typioproc;
getTypeInputInfo(typid, &typioproc, &column->scalar_io.typioparam);
fmgr_info_cxt(typioproc, &column->scalar_io.typiofunc, mcxt);
}
ReleaseSysCache(tup);
}
/* recursively populate a record field or an array element from a json/jsonb value */
static Datum
populate_record_field(ColumnIOData *col,
Oid typid,
int32 typmod,
const char *colname,
MemoryContext mcxt,
Datum defaultval,
JsValue *jsv,
bool *isnull)
{
TypeCat typcat;
check_stack_depth();
/*
* Prepare column metadata cache for the given type. Force lookup of the
* scalar_io data so that the json string hack below will work.
*/
if (col->typid != typid || col->typmod != typmod)
prepare_column_cache(col, typid, typmod, mcxt, true);
*isnull = JsValueIsNull(jsv);
typcat = col->typcat;
/* try to convert json string to a non-scalar type through input function */
if (JsValueIsString(jsv) &&
(typcat == TYPECAT_ARRAY ||
typcat == TYPECAT_COMPOSITE ||
typcat == TYPECAT_COMPOSITE_DOMAIN))
typcat = TYPECAT_SCALAR;
/* we must perform domain checks for NULLs, otherwise exit immediately */
if (*isnull &&
typcat != TYPECAT_DOMAIN &&
typcat != TYPECAT_COMPOSITE_DOMAIN)
return (Datum) 0;
switch (typcat)
{
case TYPECAT_SCALAR:
return populate_scalar(&col->scalar_io, typid, typmod, jsv);
case TYPECAT_ARRAY:
return populate_array(&col->io.array, colname, mcxt, jsv);
case TYPECAT_COMPOSITE:
case TYPECAT_COMPOSITE_DOMAIN:
return populate_composite(&col->io.composite, typid,
colname, mcxt,
DatumGetPointer(defaultval)
? DatumGetHeapTupleHeader(defaultval)
: NULL,
jsv, *isnull);
case TYPECAT_DOMAIN:
return populate_domain(&col->io.domain, typid, colname, mcxt,
jsv, *isnull);
default:
elog(ERROR, "unrecognized type category '%c'", typcat);
return (Datum) 0;
}
}
static RecordIOData *
allocate_record_info(MemoryContext mcxt, int ncolumns)
{
RecordIOData *data = (RecordIOData *)
MemoryContextAlloc(mcxt,
offsetof(RecordIOData, columns) +
ncolumns * sizeof(ColumnIOData));
data->record_type = InvalidOid;
data->record_typmod = 0;
data->ncolumns = ncolumns;
MemSet(data->columns, 0, sizeof(ColumnIOData) * ncolumns);
return data;
}
static bool
JsObjectGetField(JsObject *obj, char *field, JsValue *jsv)
{
jsv->is_json = obj->is_json;
if (jsv->is_json)
{
JsonHashEntry *hashentry = hash_search(obj->val.json_hash, field,
HASH_FIND, NULL);
jsv->val.json.type = hashentry ? hashentry->type : JSON_TOKEN_NULL;
jsv->val.json.str = jsv->val.json.type == JSON_TOKEN_NULL ? NULL :
hashentry->val;
jsv->val.json.len = jsv->val.json.str ? -1 : 0; /* null-terminated */
return hashentry != NULL;
}
else
{
jsv->val.jsonb = !obj->val.jsonb_cont ? NULL :
findJsonbValueFromContainerLen(obj->val.jsonb_cont, JB_FOBJECT,
field, strlen(field));
return jsv->val.jsonb != NULL;
}
}
/* populate a record tuple from json/jsonb value */
static HeapTupleHeader
populate_record(TupleDesc tupdesc,
RecordIOData **record_p,
HeapTupleHeader defaultval,
MemoryContext mcxt,
JsObject *obj)
{
RecordIOData *record = *record_p;
Datum *values;
bool *nulls;
HeapTuple res;
int ncolumns = tupdesc->natts;
int i;
/*
* if the input json is empty, we can only skip the rest if we were passed
* in a non-null record, since otherwise there may be issues with domain
* nulls.
*/
if (defaultval && JsObjectIsEmpty(obj))
return defaultval;
/* (re)allocate metadata cache */
if (record == NULL ||
record->ncolumns != ncolumns)
*record_p = record = allocate_record_info(mcxt, ncolumns);
/* invalidate metadata cache if the record type has changed */
if (record->record_type != tupdesc->tdtypeid ||
record->record_typmod != tupdesc->tdtypmod)
{
MemSet(record, 0, offsetof(RecordIOData, columns) +
ncolumns * sizeof(ColumnIOData));
record->record_type = tupdesc->tdtypeid;
record->record_typmod = tupdesc->tdtypmod;
record->ncolumns = ncolumns;
}
values = (Datum *) palloc(ncolumns * sizeof(Datum));
nulls = (bool *) palloc(ncolumns * sizeof(bool));
if (defaultval)
{
HeapTupleData tuple;
/* Build a temporary HeapTuple control structure */
tuple.t_len = HeapTupleHeaderGetDatumLength(defaultval);
ItemPointerSetInvalid(&(tuple.t_self));
tuple.t_tableOid = InvalidOid;
tuple.t_data = defaultval;
/* Break down the tuple into fields */
heap_deform_tuple(&tuple, tupdesc, values, nulls);
}
else
{
for (i = 0; i < ncolumns; ++i)
{
values[i] = (Datum) 0;
nulls[i] = true;
}
}
for (i = 0; i < ncolumns; ++i)
{
Form_pg_attribute att = TupleDescAttr(tupdesc, i);
char *colname = NameStr(att->attname);
JsValue field = {0};
bool found;
/* Ignore dropped columns in datatype */
if (att->attisdropped)
{
nulls[i] = true;
continue;
}
found = JsObjectGetField(obj, colname, &field);
/*
* we can't just skip here if the key wasn't found since we might have
* a domain to deal with. If we were passed in a non-null record
* datum, we assume that the existing values are valid (if they're
* not, then it's not our fault), but if we were passed in a null,
* then every field which we don't populate needs to be run through
* the input function just in case it's a domain type.
*/
if (defaultval && !found)
continue;
values[i] = populate_record_field(&record->columns[i],
att->atttypid,
att->atttypmod,
colname,
mcxt,
nulls[i] ? (Datum) 0 : values[i],
&field,
&nulls[i]);
}
res = heap_form_tuple(tupdesc, values, nulls);
pfree(values);
pfree(nulls);
return res->t_data;
}
/*
* common worker for json{b}_populate_record() and json{b}_to_record()
* is_json and have_record_arg identify the specific function
*/
static Datum
populate_record_worker(FunctionCallInfo fcinfo, const char *funcname,
bool is_json, bool have_record_arg)
{
int json_arg_num = have_record_arg ? 1 : 0;
JsValue jsv = {0};
HeapTupleHeader rec;
Datum rettuple;
JsonbValue jbv;
MemoryContext fnmcxt = fcinfo->flinfo->fn_mcxt;
PopulateRecordCache *cache = fcinfo->flinfo->fn_extra;
/*
* If first time through, identify input/result record type. Note that
* this stanza looks only at fcinfo context, which can't change during the
* query; so we may not be able to fully resolve a RECORD input type yet.
*/
if (!cache)
{
fcinfo->flinfo->fn_extra = cache =
MemoryContextAllocZero(fnmcxt, sizeof(*cache));
if (have_record_arg)
{
/*
* json{b}_populate_record case: result type will be same as first
* argument's.
*/
cache->argtype = get_fn_expr_argtype(fcinfo->flinfo, 0);
prepare_column_cache(&cache->c,
cache->argtype, -1,
fnmcxt, false);
if (cache->c.typcat != TYPECAT_COMPOSITE &&
cache->c.typcat != TYPECAT_COMPOSITE_DOMAIN)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("first argument of %s must be a row type",
funcname)));
}
else
{
/*
* json{b}_to_record case: result type is specified by calling
* query. Here it is syntactically impossible to specify the
* target type as domain-over-composite.
*/
TupleDesc tupdesc;
MemoryContext old_cxt;
if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("function returning record called in context "
"that cannot accept type record"),
errhint("Try calling the function in the FROM clause "
"using a column definition list.")));
Assert(tupdesc);
cache->argtype = tupdesc->tdtypeid;
/* Save identified tupdesc */
old_cxt = MemoryContextSwitchTo(fnmcxt);
cache->c.io.composite.tupdesc = CreateTupleDescCopy(tupdesc);
cache->c.io.composite.base_typid = tupdesc->tdtypeid;
cache->c.io.composite.base_typmod = tupdesc->tdtypmod;
MemoryContextSwitchTo(old_cxt);
}
}
/* Collect record arg if we have one */
if (have_record_arg && !PG_ARGISNULL(0))
{
rec = PG_GETARG_HEAPTUPLEHEADER(0);
/*
* When declared arg type is RECORD, identify actual record type from
* the tuple itself. Note the lookup_rowtype_tupdesc call in
* update_cached_tupdesc will fail if we're unable to do this.
*/
if (cache->argtype == RECORDOID)
{
cache->c.io.composite.base_typid = HeapTupleHeaderGetTypeId(rec);
cache->c.io.composite.base_typmod = HeapTupleHeaderGetTypMod(rec);
}
}
else
rec = NULL;
/* If no JSON argument, just return the record (if any) unchanged */
if (PG_ARGISNULL(json_arg_num))
{
if (rec)
PG_RETURN_POINTER(rec);
else
PG_RETURN_NULL();
}
jsv.is_json = is_json;
if (is_json)
{
text *json = PG_GETARG_TEXT_PP(json_arg_num);
jsv.val.json.str = VARDATA_ANY(json);
jsv.val.json.len = VARSIZE_ANY_EXHDR(json);
jsv.val.json.type = JSON_TOKEN_INVALID; /* not used in
* populate_composite() */
}
else
{
Jsonb *jb = PG_GETARG_JSONB_P(json_arg_num);
jsv.val.jsonb = &jbv;
/* fill binary jsonb value pointing to jb */
jbv.type = jbvBinary;
jbv.val.binary.data = &jb->root;
jbv.val.binary.len = VARSIZE(jb) - VARHDRSZ;
}
rettuple = populate_composite(&cache->c.io.composite, cache->argtype,
NULL, fnmcxt, rec, &jsv, false);
PG_RETURN_DATUM(rettuple);
}
/*
* get_json_object_as_hash
*
* decompose a json object into a hash table.
*/
static HTAB *
get_json_object_as_hash(char *json, int len, const char *funcname)
{
HASHCTL ctl;
HTAB *tab;
JHashState *state;
JsonLexContext *lex = makeJsonLexContextCstringLen(json, len, true);
JsonSemAction *sem;
memset(&ctl, 0, sizeof(ctl));
ctl.keysize = NAMEDATALEN;
ctl.entrysize = sizeof(JsonHashEntry);
ctl.hcxt = CurrentMemoryContext;
tab = hash_create("json object hashtable",
100,
&ctl,
HASH_ELEM | HASH_CONTEXT);
state = palloc0(sizeof(JHashState));
sem = palloc0(sizeof(JsonSemAction));
state->function_name = funcname;
state->hash = tab;
state->lex = lex;
sem->semstate = (void *) state;
sem->array_start = hash_array_start;
sem->scalar = hash_scalar;
sem->object_field_start = hash_object_field_start;
sem->object_field_end = hash_object_field_end;
pg_parse_json(lex, sem);
return tab;
}
static void
hash_object_field_start(void *state, char *fname, bool isnull)
{
JHashState *_state = (JHashState *) state;
if (_state->lex->lex_level > 1)
return;
/* remember token type */
_state->saved_token_type = _state->lex->token_type;
if (_state->lex->token_type == JSON_TOKEN_ARRAY_START ||
_state->lex->token_type == JSON_TOKEN_OBJECT_START)
{
/* remember start position of the whole text of the subobject */
_state->save_json_start = _state->lex->token_start;
}
else
{
/* must be a scalar */
_state->save_json_start = NULL;
}
}
static void
hash_object_field_end(void *state, char *fname, bool isnull)
{
JHashState *_state = (JHashState *) state;
JsonHashEntry *hashentry;
bool found;
/*
* Ignore nested fields.
*/
if (_state->lex->lex_level > 1)
return;
/*
* Ignore field names >= NAMEDATALEN - they can't match a record field.
* (Note: without this test, the hash code would truncate the string at
* NAMEDATALEN-1, and could then match against a similarly-truncated
* record field name. That would be a reasonable behavior, but this code
* has previously insisted on exact equality, so we keep this behavior.)
*/
if (strlen(fname) >= NAMEDATALEN)
return;
hashentry = hash_search(_state->hash, fname, HASH_ENTER, &found);
/*
* found being true indicates a duplicate. We don't do anything about
* that, a later field with the same name overrides the earlier field.
*/
hashentry->type = _state->saved_token_type;
Assert(isnull == (hashentry->type == JSON_TOKEN_NULL));
if (_state->save_json_start != NULL)
{
int len = _state->lex->prev_token_terminator - _state->save_json_start;
char *val = palloc((len + 1) * sizeof(char));
memcpy(val, _state->save_json_start, len);
val[len] = '\0';
hashentry->val = val;
}
else
{
/* must have had a scalar instead */
hashentry->val = _state->saved_scalar;
}
}
static void
hash_array_start(void *state)
{
JHashState *_state = (JHashState *) state;
if (_state->lex->lex_level == 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot call %s on an array", _state->function_name)));
}
static void
hash_scalar(void *state, char *token, JsonTokenType tokentype)
{
JHashState *_state = (JHashState *) state;
if (_state->lex->lex_level == 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot call %s on a scalar", _state->function_name)));
if (_state->lex->lex_level == 1)
{
_state->saved_scalar = token;
/* saved_token_type must already be set in hash_object_field_start() */
Assert(_state->saved_token_type == tokentype);
}
}
/*
* SQL function json_populate_recordset
*
* set fields in a set of records from the argument json,
* which must be an array of objects.
*
* similar to json_populate_record, but the tuple-building code
* is pushed down into the semantic action handlers so it's done
* per object in the array.
*/
Datum
jsonb_populate_recordset(PG_FUNCTION_ARGS)
{
return populate_recordset_worker(fcinfo, "jsonb_populate_recordset",
false, true);
}
Datum
jsonb_to_recordset(PG_FUNCTION_ARGS)
{
return populate_recordset_worker(fcinfo, "jsonb_to_recordset",
false, false);
}
Datum
json_populate_recordset(PG_FUNCTION_ARGS)
{
return populate_recordset_worker(fcinfo, "json_populate_recordset",
true, true);
}
Datum
json_to_recordset(PG_FUNCTION_ARGS)
{
return populate_recordset_worker(fcinfo, "json_to_recordset",
true, false);
}
static void
populate_recordset_record(PopulateRecordsetState *state, JsObject *obj)
{
PopulateRecordsetCache *cache = state->cache;
HeapTupleHeader tuphead;
HeapTupleData tuple;
/* acquire/update cached tuple descriptor */
update_cached_tupdesc(&cache->c.io.composite, cache->fn_mcxt);
/* replace record fields from json */
tuphead = populate_record(cache->c.io.composite.tupdesc,
&cache->c.io.composite.record_io,
state->rec,
cache->fn_mcxt,
obj);
/* if it's domain over composite, check domain constraints */
if (cache->c.typcat == TYPECAT_COMPOSITE_DOMAIN)
domain_check(HeapTupleHeaderGetDatum(tuphead), false,
cache->argtype,
&cache->c.io.composite.domain_info,
cache->fn_mcxt);
/* ok, save into tuplestore */
tuple.t_len = HeapTupleHeaderGetDatumLength(tuphead);
ItemPointerSetInvalid(&(tuple.t_self));
tuple.t_tableOid = InvalidOid;
tuple.t_data = tuphead;
tuplestore_puttuple(state->tuple_store, &tuple);
}
/*
* common worker for json{b}_populate_recordset() and json{b}_to_recordset()
* is_json and have_record_arg identify the specific function
*/
static Datum
populate_recordset_worker(FunctionCallInfo fcinfo, const char *funcname,
bool is_json, bool have_record_arg)
{
int json_arg_num = have_record_arg ? 1 : 0;
ReturnSetInfo *rsi;
MemoryContext old_cxt;
HeapTupleHeader rec;
PopulateRecordsetCache *cache = fcinfo->flinfo->fn_extra;
PopulateRecordsetState *state;
rsi = (ReturnSetInfo *) fcinfo->resultinfo;
if (!rsi || !IsA(rsi, ReturnSetInfo) ||
(rsi->allowedModes & SFRM_Materialize) == 0)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("set-valued function called in context that "
"cannot accept a set")));
rsi->returnMode = SFRM_Materialize;
/*
* If first time through, identify input/result record type. Note that
* this stanza looks only at fcinfo context, which can't change during the
* query; so we may not be able to fully resolve a RECORD input type yet.
*/
if (!cache)
{
fcinfo->flinfo->fn_extra = cache =
MemoryContextAllocZero(fcinfo->flinfo->fn_mcxt, sizeof(*cache));
cache->fn_mcxt = fcinfo->flinfo->fn_mcxt;
if (have_record_arg)
{
/*
* json{b}_populate_recordset case: result type will be same as
* first argument's.
*/
cache->argtype = get_fn_expr_argtype(fcinfo->flinfo, 0);
prepare_column_cache(&cache->c,
cache->argtype, -1,
cache->fn_mcxt, false);
if (cache->c.typcat != TYPECAT_COMPOSITE &&
cache->c.typcat != TYPECAT_COMPOSITE_DOMAIN)
ereport(ERROR,
(errcode(ERRCODE_DATATYPE_MISMATCH),
errmsg("first argument of %s must be a row type",
funcname)));
}
else
{
/*
* json{b}_to_recordset case: result type is specified by calling
* query. Here it is syntactically impossible to specify the
* target type as domain-over-composite.
*/
TupleDesc tupdesc;
if (get_call_result_type(fcinfo, NULL, &tupdesc) != TYPEFUNC_COMPOSITE)
ereport(ERROR,
(errcode(ERRCODE_FEATURE_NOT_SUPPORTED),
errmsg("function returning record called in context "
"that cannot accept type record"),
errhint("Try calling the function in the FROM clause "
"using a column definition list.")));
Assert(tupdesc);
cache->argtype = tupdesc->tdtypeid;
/* Save identified tupdesc */
old_cxt = MemoryContextSwitchTo(cache->fn_mcxt);
cache->c.io.composite.tupdesc = CreateTupleDescCopy(tupdesc);
cache->c.io.composite.base_typid = tupdesc->tdtypeid;
cache->c.io.composite.base_typmod = tupdesc->tdtypmod;
MemoryContextSwitchTo(old_cxt);
}
}
/* Collect record arg if we have one */
if (have_record_arg && !PG_ARGISNULL(0))
{
rec = PG_GETARG_HEAPTUPLEHEADER(0);
/*
* When declared arg type is RECORD, identify actual record type from
* the tuple itself. Note the lookup_rowtype_tupdesc call in
* update_cached_tupdesc will fail if we're unable to do this.
*/
if (cache->argtype == RECORDOID)
{
cache->c.io.composite.base_typid = HeapTupleHeaderGetTypeId(rec);
cache->c.io.composite.base_typmod = HeapTupleHeaderGetTypMod(rec);
}
}
else
rec = NULL;
/* if the json is null send back an empty set */
if (PG_ARGISNULL(json_arg_num))
PG_RETURN_NULL();
/*
* Forcibly update the cached tupdesc, to ensure we have the right tupdesc
* to return even if the JSON contains no rows.
*/
update_cached_tupdesc(&cache->c.io.composite, cache->fn_mcxt);
state = palloc0(sizeof(PopulateRecordsetState));
/* make tuplestore in a sufficiently long-lived memory context */
old_cxt = MemoryContextSwitchTo(rsi->econtext->ecxt_per_query_memory);
state->tuple_store = tuplestore_begin_heap(rsi->allowedModes &
SFRM_Materialize_Random,
false, work_mem);
MemoryContextSwitchTo(old_cxt);
state->function_name = funcname;
state->cache = cache;
state->rec = rec;
if (is_json)
{
text *json = PG_GETARG_TEXT_PP(json_arg_num);
JsonLexContext *lex;
JsonSemAction *sem;
sem = palloc0(sizeof(JsonSemAction));
lex = makeJsonLexContext(json, true);
sem->semstate = (void *) state;
sem->array_start = populate_recordset_array_start;
sem->array_element_start = populate_recordset_array_element_start;
sem->scalar = populate_recordset_scalar;
sem->object_field_start = populate_recordset_object_field_start;
sem->object_field_end = populate_recordset_object_field_end;
sem->object_start = populate_recordset_object_start;
sem->object_end = populate_recordset_object_end;
state->lex = lex;
pg_parse_json(lex, sem);
}
else
{
Jsonb *jb = PG_GETARG_JSONB_P(json_arg_num);
JsonbIterator *it;
JsonbValue v;
bool skipNested = false;
JsonbIteratorToken r;
if (JB_ROOT_IS_SCALAR(jb) || !JB_ROOT_IS_ARRAY(jb))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot call %s on a non-array",
funcname)));
it = JsonbIteratorInit(&jb->root);
while ((r = JsonbIteratorNext(&it, &v, skipNested)) != WJB_DONE)
{
skipNested = true;
if (r == WJB_ELEM)
{
JsObject obj;
if (v.type != jbvBinary ||
!JsonContainerIsObject(v.val.binary.data))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("argument of %s must be an array of objects",
funcname)));
obj.is_json = false;
obj.val.jsonb_cont = v.val.binary.data;
populate_recordset_record(state, &obj);
}
}
}
/*
* Note: we must copy the cached tupdesc because the executor will free
* the passed-back setDesc, but we want to hang onto the cache in case
* we're called again in the same query.
*/
rsi->setResult = state->tuple_store;
rsi->setDesc = CreateTupleDescCopy(cache->c.io.composite.tupdesc);
PG_RETURN_NULL();
}
static void
populate_recordset_object_start(void *state)
{
PopulateRecordsetState *_state = (PopulateRecordsetState *) state;
int lex_level = _state->lex->lex_level;
HASHCTL ctl;
/* Reject object at top level: we must have an array at level 0 */
if (lex_level == 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot call %s on an object",
_state->function_name)));
/* Nested objects require no special processing */
if (lex_level > 1)
return;
/* Object at level 1: set up a new hash table for this object */
memset(&ctl, 0, sizeof(ctl));
ctl.keysize = NAMEDATALEN;
ctl.entrysize = sizeof(JsonHashEntry);
ctl.hcxt = CurrentMemoryContext;
_state->json_hash = hash_create("json object hashtable",
100,
&ctl,
HASH_ELEM | HASH_CONTEXT);
}
static void
populate_recordset_object_end(void *state)
{
PopulateRecordsetState *_state = (PopulateRecordsetState *) state;
JsObject obj;
/* Nested objects require no special processing */
if (_state->lex->lex_level > 1)
return;
obj.is_json = true;
obj.val.json_hash = _state->json_hash;
/* Otherwise, construct and return a tuple based on this level-1 object */
populate_recordset_record(_state, &obj);
/* Done with hash for this object */
hash_destroy(_state->json_hash);
_state->json_hash = NULL;
}
static void
populate_recordset_array_element_start(void *state, bool isnull)
{
PopulateRecordsetState *_state = (PopulateRecordsetState *) state;
if (_state->lex->lex_level == 1 &&
_state->lex->token_type != JSON_TOKEN_OBJECT_START)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("argument of %s must be an array of objects",
_state->function_name)));
}
static void
populate_recordset_array_start(void *state)
{
/* nothing to do */
}
static void
populate_recordset_scalar(void *state, char *token, JsonTokenType tokentype)
{
PopulateRecordsetState *_state = (PopulateRecordsetState *) state;
if (_state->lex->lex_level == 0)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot call %s on a scalar",
_state->function_name)));
if (_state->lex->lex_level == 2)
_state->saved_scalar = token;
}
static void
populate_recordset_object_field_start(void *state, char *fname, bool isnull)
{
PopulateRecordsetState *_state = (PopulateRecordsetState *) state;
if (_state->lex->lex_level > 2)
return;
_state->saved_token_type = _state->lex->token_type;
if (_state->lex->token_type == JSON_TOKEN_ARRAY_START ||
_state->lex->token_type == JSON_TOKEN_OBJECT_START)
{
_state->save_json_start = _state->lex->token_start;
}
else
{
_state->save_json_start = NULL;
}
}
static void
populate_recordset_object_field_end(void *state, char *fname, bool isnull)
{
PopulateRecordsetState *_state = (PopulateRecordsetState *) state;
JsonHashEntry *hashentry;
bool found;
/*
* Ignore nested fields.
*/
if (_state->lex->lex_level > 2)
return;
/*
* Ignore field names >= NAMEDATALEN - they can't match a record field.
* (Note: without this test, the hash code would truncate the string at
* NAMEDATALEN-1, and could then match against a similarly-truncated
* record field name. That would be a reasonable behavior, but this code
* has previously insisted on exact equality, so we keep this behavior.)
*/
if (strlen(fname) >= NAMEDATALEN)
return;
hashentry = hash_search(_state->json_hash, fname, HASH_ENTER, &found);
/*
* found being true indicates a duplicate. We don't do anything about
* that, a later field with the same name overrides the earlier field.
*/
hashentry->type = _state->saved_token_type;
Assert(isnull == (hashentry->type == JSON_TOKEN_NULL));
if (_state->save_json_start != NULL)
{
int len = _state->lex->prev_token_terminator - _state->save_json_start;
char *val = palloc((len + 1) * sizeof(char));
memcpy(val, _state->save_json_start, len);
val[len] = '\0';
hashentry->val = val;
}
else
{
/* must have had a scalar instead */
hashentry->val = _state->saved_scalar;
}
}
/*
* findJsonbValueFromContainer() wrapper that sets up JsonbValue key string.
*/
static JsonbValue *
findJsonbValueFromContainerLen(JsonbContainer *container, uint32 flags,
char *key, uint32 keylen)
{
JsonbValue k;
k.type = jbvString;
k.val.string.val = key;
k.val.string.len = keylen;
return findJsonbValueFromContainer(container, flags, &k);
}
/*
* Semantic actions for json_strip_nulls.
*
* Simply repeat the input on the output unless we encounter
* a null object field. State for this is set when the field
* is started and reset when the scalar action (which must be next)
* is called.
*/
static void
sn_object_start(void *state)
{
StripnullState *_state = (StripnullState *) state;
appendStringInfoCharMacro(_state->strval, '{');
}
static void
sn_object_end(void *state)
{
StripnullState *_state = (StripnullState *) state;
appendStringInfoCharMacro(_state->strval, '}');
}
static void
sn_array_start(void *state)
{
StripnullState *_state = (StripnullState *) state;
appendStringInfoCharMacro(_state->strval, '[');
}
static void
sn_array_end(void *state)
{
StripnullState *_state = (StripnullState *) state;
appendStringInfoCharMacro(_state->strval, ']');
}
static void
sn_object_field_start(void *state, char *fname, bool isnull)
{
StripnullState *_state = (StripnullState *) state;
if (isnull)
{
/*
* The next thing must be a scalar or isnull couldn't be true, so
* there is no danger of this state being carried down into a nested
* object or array. The flag will be reset in the scalar action.
*/
_state->skip_next_null = true;
return;
}
if (_state->strval->data[_state->strval->len - 1] != '{')
appendStringInfoCharMacro(_state->strval, ',');
/*
* Unfortunately we don't have the quoted and escaped string any more, so
* we have to re-escape it.
*/
escape_json(_state->strval, fname);
appendStringInfoCharMacro(_state->strval, ':');
}
static void
sn_array_element_start(void *state, bool isnull)
{
StripnullState *_state = (StripnullState *) state;
if (_state->strval->data[_state->strval->len - 1] != '[')
appendStringInfoCharMacro(_state->strval, ',');
}
static void
sn_scalar(void *state, char *token, JsonTokenType tokentype)
{
StripnullState *_state = (StripnullState *) state;
if (_state->skip_next_null)
{
Assert(tokentype == JSON_TOKEN_NULL);
_state->skip_next_null = false;
return;
}
if (tokentype == JSON_TOKEN_STRING)
escape_json(_state->strval, token);
else
appendStringInfoString(_state->strval, token);
}
/*
* SQL function json_strip_nulls(json) -> json
*/
Datum
json_strip_nulls(PG_FUNCTION_ARGS)
{
text *json = PG_GETARG_TEXT_PP(0);
StripnullState *state;
JsonLexContext *lex;
JsonSemAction *sem;
lex = makeJsonLexContext(json, true);
state = palloc0(sizeof(StripnullState));
sem = palloc0(sizeof(JsonSemAction));
state->strval = makeStringInfo();
state->skip_next_null = false;
state->lex = lex;
sem->semstate = (void *) state;
sem->object_start = sn_object_start;
sem->object_end = sn_object_end;
sem->array_start = sn_array_start;
sem->array_end = sn_array_end;
sem->scalar = sn_scalar;
sem->array_element_start = sn_array_element_start;
sem->object_field_start = sn_object_field_start;
pg_parse_json(lex, sem);
PG_RETURN_TEXT_P(cstring_to_text_with_len(state->strval->data,
state->strval->len));
}
/*
* SQL function jsonb_strip_nulls(jsonb) -> jsonb
*/
Datum
jsonb_strip_nulls(PG_FUNCTION_ARGS)
{
Jsonb *jb = PG_GETARG_JSONB_P(0);
JsonbIterator *it;
JsonbParseState *parseState = NULL;
JsonbValue *res = NULL;
JsonbValue v,
k;
JsonbIteratorToken type;
bool last_was_key = false;
if (JB_ROOT_IS_SCALAR(jb))
PG_RETURN_POINTER(jb);
it = JsonbIteratorInit(&jb->root);
while ((type = JsonbIteratorNext(&it, &v, false)) != WJB_DONE)
{
Assert(!(type == WJB_KEY && last_was_key));
if (type == WJB_KEY)
{
/* stash the key until we know if it has a null value */
k = v;
last_was_key = true;
continue;
}
if (last_was_key)
{
/* if the last element was a key this one can't be */
last_was_key = false;
/* skip this field if value is null */
if (type == WJB_VALUE && v.type == jbvNull)
continue;
/* otherwise, do a delayed push of the key */
(void) pushJsonbValue(&parseState, WJB_KEY, &k);
}
if (type == WJB_VALUE || type == WJB_ELEM)
res = pushJsonbValue(&parseState, type, &v);
else
res = pushJsonbValue(&parseState, type, NULL);
}
Assert(res != NULL);
PG_RETURN_POINTER(JsonbValueToJsonb(res));
}
/*
* Add values from the jsonb to the parse state.
*
* If the parse state container is an object, the jsonb is pushed as
* a value, not a key.
*
* This needs to be done using an iterator because pushJsonbValue doesn't
* like getting jbvBinary values, so we can't just push jb as a whole.
*/
static void
addJsonbToParseState(JsonbParseState **jbps, Jsonb *jb)
{
JsonbIterator *it;
JsonbValue *o = &(*jbps)->contVal;
JsonbValue v;
JsonbIteratorToken type;
it = JsonbIteratorInit(&jb->root);
Assert(o->type == jbvArray || o->type == jbvObject);
if (JB_ROOT_IS_SCALAR(jb))
{
(void) JsonbIteratorNext(&it, &v, false); /* skip array header */
Assert(v.type == jbvArray);
(void) JsonbIteratorNext(&it, &v, false); /* fetch scalar value */
switch (o->type)
{
case jbvArray:
(void) pushJsonbValue(jbps, WJB_ELEM, &v);
break;
case jbvObject:
(void) pushJsonbValue(jbps, WJB_VALUE, &v);
break;
default:
elog(ERROR, "unexpected parent of nested structure");
}
}
else
{
while ((type = JsonbIteratorNext(&it, &v, false)) != WJB_DONE)
{
if (type == WJB_KEY || type == WJB_VALUE || type == WJB_ELEM)
(void) pushJsonbValue(jbps, type, &v);
else
(void) pushJsonbValue(jbps, type, NULL);
}
}
}
/*
* SQL function jsonb_pretty (jsonb)
*
* Pretty-printed text for the jsonb
*/
Datum
jsonb_pretty(PG_FUNCTION_ARGS)
{
Jsonb *jb = PG_GETARG_JSONB_P(0);
StringInfo str = makeStringInfo();
JsonbToCStringIndent(str, &jb->root, VARSIZE(jb));
PG_RETURN_TEXT_P(cstring_to_text_with_len(str->data, str->len));
}
/*
* SQL function jsonb_concat (jsonb, jsonb)
*
* function for || operator
*/
Datum
jsonb_concat(PG_FUNCTION_ARGS)
{
Jsonb *jb1 = PG_GETARG_JSONB_P(0);
Jsonb *jb2 = PG_GETARG_JSONB_P(1);
JsonbParseState *state = NULL;
JsonbValue *res;
JsonbIterator *it1,
*it2;
/*
* If one of the jsonb is empty, just return the other if it's not scalar
* and both are of the same kind. If it's a scalar or they are of
* different kinds we need to perform the concatenation even if one is
* empty.
*/
if (JB_ROOT_IS_OBJECT(jb1) == JB_ROOT_IS_OBJECT(jb2))
{
if (JB_ROOT_COUNT(jb1) == 0 && !JB_ROOT_IS_SCALAR(jb2))
PG_RETURN_JSONB_P(jb2);
else if (JB_ROOT_COUNT(jb2) == 0 && !JB_ROOT_IS_SCALAR(jb1))
PG_RETURN_JSONB_P(jb1);
}
it1 = JsonbIteratorInit(&jb1->root);
it2 = JsonbIteratorInit(&jb2->root);
res = IteratorConcat(&it1, &it2, &state);
Assert(res != NULL);
PG_RETURN_JSONB_P(JsonbValueToJsonb(res));
}
/*
* SQL function jsonb_delete (jsonb, text)
*
* return a copy of the jsonb with the indicated item
* removed.
*/
Datum
jsonb_delete(PG_FUNCTION_ARGS)
{
Jsonb *in = PG_GETARG_JSONB_P(0);
text *key = PG_GETARG_TEXT_PP(1);
char *keyptr = VARDATA_ANY(key);
int keylen = VARSIZE_ANY_EXHDR(key);
JsonbParseState *state = NULL;
JsonbIterator *it;
JsonbValue v,
*res = NULL;
bool skipNested = false;
JsonbIteratorToken r;
if (JB_ROOT_IS_SCALAR(in))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot delete from scalar")));
if (JB_ROOT_COUNT(in) == 0)
PG_RETURN_JSONB_P(in);
it = JsonbIteratorInit(&in->root);
while ((r = JsonbIteratorNext(&it, &v, skipNested)) != WJB_DONE)
{
skipNested = true;
if ((r == WJB_ELEM || r == WJB_KEY) &&
(v.type == jbvString && keylen == v.val.string.len &&
memcmp(keyptr, v.val.string.val, keylen) == 0))
{
/* skip corresponding value as well */
if (r == WJB_KEY)
(void) JsonbIteratorNext(&it, &v, true);
continue;
}
res = pushJsonbValue(&state, r, r < WJB_BEGIN_ARRAY ? &v : NULL);
}
Assert(res != NULL);
PG_RETURN_JSONB_P(JsonbValueToJsonb(res));
}
/*
* SQL function jsonb_delete (jsonb, variadic text[])
*
* return a copy of the jsonb with the indicated items
* removed.
*/
Datum
jsonb_delete_array(PG_FUNCTION_ARGS)
{
Jsonb *in = PG_GETARG_JSONB_P(0);
ArrayType *keys = PG_GETARG_ARRAYTYPE_P(1);
Datum *keys_elems;
bool *keys_nulls;
int keys_len;
JsonbParseState *state = NULL;
JsonbIterator *it;
JsonbValue v,
*res = NULL;
bool skipNested = false;
JsonbIteratorToken r;
if (ARR_NDIM(keys) > 1)
ereport(ERROR,
(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
errmsg("wrong number of array subscripts")));
if (JB_ROOT_IS_SCALAR(in))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot delete from scalar")));
if (JB_ROOT_COUNT(in) == 0)
PG_RETURN_JSONB_P(in);
deconstruct_array(keys, TEXTOID, -1, false, 'i',
&keys_elems, &keys_nulls, &keys_len);
if (keys_len == 0)
PG_RETURN_JSONB_P(in);
it = JsonbIteratorInit(&in->root);
while ((r = JsonbIteratorNext(&it, &v, skipNested)) != WJB_DONE)
{
skipNested = true;
if ((r == WJB_ELEM || r == WJB_KEY) && v.type == jbvString)
{
int i;
bool found = false;
for (i = 0; i < keys_len; i++)
{
char *keyptr;
int keylen;
if (keys_nulls[i])
continue;
keyptr = VARDATA_ANY(keys_elems[i]);
keylen = VARSIZE_ANY_EXHDR(keys_elems[i]);
if (keylen == v.val.string.len &&
memcmp(keyptr, v.val.string.val, keylen) == 0)
{
found = true;
break;
}
}
if (found)
{
/* skip corresponding value as well */
if (r == WJB_KEY)
(void) JsonbIteratorNext(&it, &v, true);
continue;
}
}
res = pushJsonbValue(&state, r, r < WJB_BEGIN_ARRAY ? &v : NULL);
}
Assert(res != NULL);
PG_RETURN_JSONB_P(JsonbValueToJsonb(res));
}
/*
* SQL function jsonb_delete (jsonb, int)
*
* return a copy of the jsonb with the indicated item
* removed. Negative int means count back from the
* end of the items.
*/
Datum
jsonb_delete_idx(PG_FUNCTION_ARGS)
{
Jsonb *in = PG_GETARG_JSONB_P(0);
int idx = PG_GETARG_INT32(1);
JsonbParseState *state = NULL;
JsonbIterator *it;
uint32 i = 0,
n;
JsonbValue v,
*res = NULL;
JsonbIteratorToken r;
if (JB_ROOT_IS_SCALAR(in))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot delete from scalar")));
if (JB_ROOT_IS_OBJECT(in))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot delete from object using integer index")));
if (JB_ROOT_COUNT(in) == 0)
PG_RETURN_JSONB_P(in);
it = JsonbIteratorInit(&in->root);
r = JsonbIteratorNext(&it, &v, false);
Assert(r == WJB_BEGIN_ARRAY);
n = v.val.array.nElems;
if (idx < 0)
{
if (-idx > n)
idx = n;
else
idx = n + idx;
}
if (idx >= n)
PG_RETURN_JSONB_P(in);
pushJsonbValue(&state, r, NULL);
while ((r = JsonbIteratorNext(&it, &v, true)) != WJB_DONE)
{
if (r == WJB_ELEM)
{
if (i++ == idx)
continue;
}
res = pushJsonbValue(&state, r, r < WJB_BEGIN_ARRAY ? &v : NULL);
}
Assert(res != NULL);
PG_RETURN_JSONB_P(JsonbValueToJsonb(res));
}
/*
* SQL function jsonb_set(jsonb, text[], jsonb, boolean)
*
*/
Datum
jsonb_set(PG_FUNCTION_ARGS)
{
Jsonb *in = PG_GETARG_JSONB_P(0);
ArrayType *path = PG_GETARG_ARRAYTYPE_P(1);
Jsonb *newval = PG_GETARG_JSONB_P(2);
bool create = PG_GETARG_BOOL(3);
JsonbValue *res = NULL;
Datum *path_elems;
bool *path_nulls;
int path_len;
JsonbIterator *it;
JsonbParseState *st = NULL;
if (ARR_NDIM(path) > 1)
ereport(ERROR,
(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
errmsg("wrong number of array subscripts")));
if (JB_ROOT_IS_SCALAR(in))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot set path in scalar")));
if (JB_ROOT_COUNT(in) == 0 && !create)
PG_RETURN_JSONB_P(in);
deconstruct_array(path, TEXTOID, -1, false, 'i',
&path_elems, &path_nulls, &path_len);
if (path_len == 0)
PG_RETURN_JSONB_P(in);
it = JsonbIteratorInit(&in->root);
res = setPath(&it, path_elems, path_nulls, path_len, &st,
0, newval, create ? JB_PATH_CREATE : JB_PATH_REPLACE);
Assert(res != NULL);
PG_RETURN_JSONB_P(JsonbValueToJsonb(res));
}
/*
* SQL function jsonb_delete_path(jsonb, text[])
*/
Datum
jsonb_delete_path(PG_FUNCTION_ARGS)
{
Jsonb *in = PG_GETARG_JSONB_P(0);
ArrayType *path = PG_GETARG_ARRAYTYPE_P(1);
JsonbValue *res = NULL;
Datum *path_elems;
bool *path_nulls;
int path_len;
JsonbIterator *it;
JsonbParseState *st = NULL;
if (ARR_NDIM(path) > 1)
ereport(ERROR,
(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
errmsg("wrong number of array subscripts")));
if (JB_ROOT_IS_SCALAR(in))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot delete path in scalar")));
if (JB_ROOT_COUNT(in) == 0)
PG_RETURN_JSONB_P(in);
deconstruct_array(path, TEXTOID, -1, false, 'i',
&path_elems, &path_nulls, &path_len);
if (path_len == 0)
PG_RETURN_JSONB_P(in);
it = JsonbIteratorInit(&in->root);
res = setPath(&it, path_elems, path_nulls, path_len, &st,
0, NULL, JB_PATH_DELETE);
Assert(res != NULL);
PG_RETURN_JSONB_P(JsonbValueToJsonb(res));
}
/*
* SQL function jsonb_insert(jsonb, text[], jsonb, boolean)
*
*/
Datum
jsonb_insert(PG_FUNCTION_ARGS)
{
Jsonb *in = PG_GETARG_JSONB_P(0);
ArrayType *path = PG_GETARG_ARRAYTYPE_P(1);
Jsonb *newval = PG_GETARG_JSONB_P(2);
bool after = PG_GETARG_BOOL(3);
JsonbValue *res = NULL;
Datum *path_elems;
bool *path_nulls;
int path_len;
JsonbIterator *it;
JsonbParseState *st = NULL;
if (ARR_NDIM(path) > 1)
ereport(ERROR,
(errcode(ERRCODE_ARRAY_SUBSCRIPT_ERROR),
errmsg("wrong number of array subscripts")));
if (JB_ROOT_IS_SCALAR(in))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot set path in scalar")));
deconstruct_array(path, TEXTOID, -1, false, 'i',
&path_elems, &path_nulls, &path_len);
if (path_len == 0)
PG_RETURN_JSONB_P(in);
it = JsonbIteratorInit(&in->root);
res = setPath(&it, path_elems, path_nulls, path_len, &st, 0, newval,
after ? JB_PATH_INSERT_AFTER : JB_PATH_INSERT_BEFORE);
Assert(res != NULL);
PG_RETURN_JSONB_P(JsonbValueToJsonb(res));
}
/*
* Iterate over all jsonb objects and merge them into one.
* The logic of this function copied from the same hstore function,
* except the case, when it1 & it2 represents jbvObject.
* In that case we just append the content of it2 to it1 without any
* verifications.
*/
static JsonbValue *
IteratorConcat(JsonbIterator **it1, JsonbIterator **it2,
JsonbParseState **state)
{
JsonbValue v1,
v2,
*res = NULL;
JsonbIteratorToken r1,
r2,
rk1,
rk2;
r1 = rk1 = JsonbIteratorNext(it1, &v1, false);
r2 = rk2 = JsonbIteratorNext(it2, &v2, false);
/*
* Both elements are objects.
*/
if (rk1 == WJB_BEGIN_OBJECT && rk2 == WJB_BEGIN_OBJECT)
{
/*
* Append the all tokens from v1 to res, except last WJB_END_OBJECT
* (because res will not be finished yet).
*/
pushJsonbValue(state, r1, NULL);
while ((r1 = JsonbIteratorNext(it1, &v1, true)) != WJB_END_OBJECT)
pushJsonbValue(state, r1, &v1);
/*
* Append the all tokens from v2 to res, include last WJB_END_OBJECT
* (the concatenation will be completed).
*/
while ((r2 = JsonbIteratorNext(it2, &v2, true)) != WJB_DONE)
res = pushJsonbValue(state, r2, r2 != WJB_END_OBJECT ? &v2 : NULL);
}
/*
* Both elements are arrays (either can be scalar).
*/
else if (rk1 == WJB_BEGIN_ARRAY && rk2 == WJB_BEGIN_ARRAY)
{
pushJsonbValue(state, r1, NULL);
while ((r1 = JsonbIteratorNext(it1, &v1, true)) != WJB_END_ARRAY)
{
Assert(r1 == WJB_ELEM);
pushJsonbValue(state, r1, &v1);
}
while ((r2 = JsonbIteratorNext(it2, &v2, true)) != WJB_END_ARRAY)
{
Assert(r2 == WJB_ELEM);
pushJsonbValue(state, WJB_ELEM, &v2);
}
res = pushJsonbValue(state, WJB_END_ARRAY, NULL /* signal to sort */ );
}
/* have we got array || object or object || array? */
else if (((rk1 == WJB_BEGIN_ARRAY && !(*it1)->isScalar) && rk2 == WJB_BEGIN_OBJECT) ||
(rk1 == WJB_BEGIN_OBJECT && (rk2 == WJB_BEGIN_ARRAY && !(*it2)->isScalar)))
{
JsonbIterator **it_array = rk1 == WJB_BEGIN_ARRAY ? it1 : it2;
JsonbIterator **it_object = rk1 == WJB_BEGIN_OBJECT ? it1 : it2;
bool prepend = (rk1 == WJB_BEGIN_OBJECT);
pushJsonbValue(state, WJB_BEGIN_ARRAY, NULL);
if (prepend)
{
pushJsonbValue(state, WJB_BEGIN_OBJECT, NULL);
while ((r1 = JsonbIteratorNext(it_object, &v1, true)) != WJB_DONE)
pushJsonbValue(state, r1, r1 != WJB_END_OBJECT ? &v1 : NULL);
while ((r2 = JsonbIteratorNext(it_array, &v2, true)) != WJB_DONE)
res = pushJsonbValue(state, r2, r2 != WJB_END_ARRAY ? &v2 : NULL);
}
else
{
while ((r1 = JsonbIteratorNext(it_array, &v1, true)) != WJB_END_ARRAY)
pushJsonbValue(state, r1, &v1);
pushJsonbValue(state, WJB_BEGIN_OBJECT, NULL);
while ((r2 = JsonbIteratorNext(it_object, &v2, true)) != WJB_DONE)
pushJsonbValue(state, r2, r2 != WJB_END_OBJECT ? &v2 : NULL);
res = pushJsonbValue(state, WJB_END_ARRAY, NULL);
}
}
else
{
/*
* This must be scalar || object or object || scalar, as that's all
* that's left. Both of these make no sense, so error out.
*/
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("invalid concatenation of jsonb objects")));
}
return res;
}
/*
* Do most of the heavy work for jsonb_set/jsonb_insert
*
* If JB_PATH_DELETE bit is set in op_type, the element is to be removed.
*
* If any bit mentioned in JB_PATH_CREATE_OR_INSERT is set in op_type,
* we create the new value if the key or array index does not exist.
*
* Bits JB_PATH_INSERT_BEFORE and JB_PATH_INSERT_AFTER in op_type
* behave as JB_PATH_CREATE if new value is inserted in JsonbObject.
*
* All path elements before the last must already exist
* whatever bits in op_type are set, or nothing is done.
*/
static JsonbValue *
setPath(JsonbIterator **it, Datum *path_elems,
bool *path_nulls, int path_len,
JsonbParseState **st, int level, Jsonb *newval, int op_type)
{
JsonbValue v;
JsonbIteratorToken r;
JsonbValue *res;
check_stack_depth();
if (path_nulls[level])
ereport(ERROR,
(errcode(ERRCODE_NULL_VALUE_NOT_ALLOWED),
errmsg("path element at position %d is null",
level + 1)));
r = JsonbIteratorNext(it, &v, false);
switch (r)
{
case WJB_BEGIN_ARRAY:
(void) pushJsonbValue(st, r, NULL);
setPathArray(it, path_elems, path_nulls, path_len, st, level,
newval, v.val.array.nElems, op_type);
r = JsonbIteratorNext(it, &v, false);
Assert(r == WJB_END_ARRAY);
res = pushJsonbValue(st, r, NULL);
break;
case WJB_BEGIN_OBJECT:
(void) pushJsonbValue(st, r, NULL);
setPathObject(it, path_elems, path_nulls, path_len, st, level,
newval, v.val.object.nPairs, op_type);
r = JsonbIteratorNext(it, &v, true);
Assert(r == WJB_END_OBJECT);
res = pushJsonbValue(st, r, NULL);
break;
case WJB_ELEM:
case WJB_VALUE:
res = pushJsonbValue(st, r, &v);
break;
default:
elog(ERROR, "unrecognized iterator result: %d", (int) r);
res = NULL; /* keep compiler quiet */
break;
}
return res;
}
/*
* Object walker for setPath
*/
static void
setPathObject(JsonbIterator **it, Datum *path_elems, bool *path_nulls,
int path_len, JsonbParseState **st, int level,
Jsonb *newval, uint32 npairs, int op_type)
{
JsonbValue v;
int i;
JsonbValue k;
bool done = false;
if (level >= path_len || path_nulls[level])
done = true;
/* empty object is a special case for create */
if ((npairs == 0) && (op_type & JB_PATH_CREATE_OR_INSERT) &&
(level == path_len - 1))
{
JsonbValue newkey;
newkey.type = jbvString;
newkey.val.string.len = VARSIZE_ANY_EXHDR(path_elems[level]);
newkey.val.string.val = VARDATA_ANY(path_elems[level]);
(void) pushJsonbValue(st, WJB_KEY, &newkey);
addJsonbToParseState(st, newval);
}
for (i = 0; i < npairs; i++)
{
JsonbIteratorToken r = JsonbIteratorNext(it, &k, true);
Assert(r == WJB_KEY);
if (!done &&
k.val.string.len == VARSIZE_ANY_EXHDR(path_elems[level]) &&
memcmp(k.val.string.val, VARDATA_ANY(path_elems[level]),
k.val.string.len) == 0)
{
if (level == path_len - 1)
{
/*
* called from jsonb_insert(), it forbids redefining an
* existing value
*/
if (op_type & (JB_PATH_INSERT_BEFORE | JB_PATH_INSERT_AFTER))
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("cannot replace existing key"),
errhint("Try using the function jsonb_set "
"to replace key value.")));
r = JsonbIteratorNext(it, &v, true); /* skip value */
if (!(op_type & JB_PATH_DELETE))
{
(void) pushJsonbValue(st, WJB_KEY, &k);
addJsonbToParseState(st, newval);
}
done = true;
}
else
{
(void) pushJsonbValue(st, r, &k);
setPath(it, path_elems, path_nulls, path_len,
st, level + 1, newval, op_type);
}
}
else
{
if ((op_type & JB_PATH_CREATE_OR_INSERT) && !done &&
level == path_len - 1 && i == npairs - 1)
{
JsonbValue newkey;
newkey.type = jbvString;
newkey.val.string.len = VARSIZE_ANY_EXHDR(path_elems[level]);
newkey.val.string.val = VARDATA_ANY(path_elems[level]);
(void) pushJsonbValue(st, WJB_KEY, &newkey);
addJsonbToParseState(st, newval);
}
(void) pushJsonbValue(st, r, &k);
r = JsonbIteratorNext(it, &v, false);
(void) pushJsonbValue(st, r, r < WJB_BEGIN_ARRAY ? &v : NULL);
if (r == WJB_BEGIN_ARRAY || r == WJB_BEGIN_OBJECT)
{
int walking_level = 1;
while (walking_level != 0)
{
r = JsonbIteratorNext(it, &v, false);
if (r == WJB_BEGIN_ARRAY || r == WJB_BEGIN_OBJECT)
++walking_level;
if (r == WJB_END_ARRAY || r == WJB_END_OBJECT)
--walking_level;
(void) pushJsonbValue(st, r, r < WJB_BEGIN_ARRAY ? &v : NULL);
}
}
}
}
}
/*
* Array walker for setPath
*/
static void
setPathArray(JsonbIterator **it, Datum *path_elems, bool *path_nulls,
int path_len, JsonbParseState **st, int level,
Jsonb *newval, uint32 nelems, int op_type)
{
JsonbValue v;
int idx,
i;
bool done = false;
/* pick correct index */
if (level < path_len && !path_nulls[level])
{
char *c = TextDatumGetCString(path_elems[level]);
long lindex;
char *badp;
errno = 0;
lindex = strtol(c, &badp, 10);
if (errno != 0 || badp == c || *badp != '\0' || lindex > INT_MAX ||
lindex < INT_MIN)
ereport(ERROR,
(errcode(ERRCODE_INVALID_TEXT_REPRESENTATION),
errmsg("path element at position %d is not an integer: \"%s\"",
level + 1, c)));
idx = lindex;
}
else
idx = nelems;
if (idx < 0)
{
if (-idx > nelems)
idx = INT_MIN;
else
idx = nelems + idx;
}
if (idx > 0 && idx > nelems)
idx = nelems;
/*
* if we're creating, and idx == INT_MIN, we prepend the new value to the
* array also if the array is empty - in which case we don't really care
* what the idx value is
*/
if ((idx == INT_MIN || nelems == 0) && (level == path_len - 1) &&
(op_type & JB_PATH_CREATE_OR_INSERT))
{
Assert(newval != NULL);
addJsonbToParseState(st, newval);
done = true;
}
/* iterate over the array elements */
for (i = 0; i < nelems; i++)
{
JsonbIteratorToken r;
if (i == idx && level < path_len)
{
if (level == path_len - 1)
{
r = JsonbIteratorNext(it, &v, true); /* skip */
if (op_type & (JB_PATH_INSERT_BEFORE | JB_PATH_CREATE))
addJsonbToParseState(st, newval);
/*
* We should keep current value only in case of
* JB_PATH_INSERT_BEFORE or JB_PATH_INSERT_AFTER because
* otherwise it should be deleted or replaced
*/
if (op_type & (JB_PATH_INSERT_AFTER | JB_PATH_INSERT_BEFORE))
(void) pushJsonbValue(st, r, &v);
if (op_type & (JB_PATH_INSERT_AFTER | JB_PATH_REPLACE))
addJsonbToParseState(st, newval);
done = true;
}
else
(void) setPath(it, path_elems, path_nulls, path_len,
st, level + 1, newval, op_type);
}
else
{
r = JsonbIteratorNext(it, &v, false);
(void) pushJsonbValue(st, r, r < WJB_BEGIN_ARRAY ? &v : NULL);
if (r == WJB_BEGIN_ARRAY || r == WJB_BEGIN_OBJECT)
{
int walking_level = 1;
while (walking_level != 0)
{
r = JsonbIteratorNext(it, &v, false);
if (r == WJB_BEGIN_ARRAY || r == WJB_BEGIN_OBJECT)
++walking_level;
if (r == WJB_END_ARRAY || r == WJB_END_OBJECT)
--walking_level;
(void) pushJsonbValue(st, r, r < WJB_BEGIN_ARRAY ? &v : NULL);
}
}
if ((op_type & JB_PATH_CREATE_OR_INSERT) && !done &&
level == path_len - 1 && i == nelems - 1)
{
addJsonbToParseState(st, newval);
}
}
}
}
/*
* Parse information about what elements of a jsonb document we want to iterate
* in functions iterate_json(b)_values. This information is presented in jsonb
* format, so that it can be easily extended in the future.
*/
uint32
parse_jsonb_index_flags(Jsonb *jb)
{
JsonbIterator *it;
JsonbValue v;
JsonbIteratorToken type;
uint32 flags = 0;
it = JsonbIteratorInit(&jb->root);
type = JsonbIteratorNext(&it, &v, false);
/*
* We iterate over array (scalar internally is represented as array, so,
* we will accept it too) to check all its elements. Flag names are
* chosen the same as jsonb_typeof uses.
*/
if (type != WJB_BEGIN_ARRAY)
ereport(ERROR, (errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("wrong flag type, only arrays and scalars are allowed")));
while ((type = JsonbIteratorNext(&it, &v, false)) == WJB_ELEM)
{
if (v.type != jbvString)
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("flag array element is not a string"),
errhint("Possible values are: \"string\", \"numeric\", \"boolean\", \"key\", and \"all\".")));
if (v.val.string.len == 3 &&
pg_strncasecmp(v.val.string.val, "all", 3) == 0)
flags |= jtiAll;
else if (v.val.string.len == 3 &&
pg_strncasecmp(v.val.string.val, "key", 3) == 0)
flags |= jtiKey;
else if (v.val.string.len == 6 &&
pg_strncasecmp(v.val.string.val, "string", 5) == 0)
flags |= jtiString;
else if (v.val.string.len == 7 &&
pg_strncasecmp(v.val.string.val, "numeric", 7) == 0)
flags |= jtiNumeric;
else if (v.val.string.len == 7 &&
pg_strncasecmp(v.val.string.val, "boolean", 7) == 0)
flags |= jtiBool;
else
ereport(ERROR,
(errcode(ERRCODE_INVALID_PARAMETER_VALUE),
errmsg("wrong flag in flag array: \"%s\"",
pnstrdup(v.val.string.val, v.val.string.len)),
errhint("Possible values are: \"string\", \"numeric\", \"boolean\", \"key\", and \"all\".")));
}
/* expect end of array now */
if (type != WJB_END_ARRAY)
elog(ERROR, "unexpected end of flag array");
/* get final WJB_DONE and free iterator */
type = JsonbIteratorNext(&it, &v, false);
if (type != WJB_DONE)
elog(ERROR, "unexpected end of flag array");
return flags;
}
/*
* Iterate over jsonb values or elements, specified by flags, and pass them
* together with an iteration state to a specified JsonIterateStringValuesAction.
*/
void
iterate_jsonb_values(Jsonb *jb, uint32 flags, void *state,
JsonIterateStringValuesAction action)
{
JsonbIterator *it;
JsonbValue v;
JsonbIteratorToken type;
it = JsonbIteratorInit(&jb->root);
/*
* Just recursively iterating over jsonb and call callback on all
* corresponding elements
*/
while ((type = JsonbIteratorNext(&it, &v, false)) != WJB_DONE)
{
if (type == WJB_KEY)
{
if (flags & jtiKey)
action(state, v.val.string.val, v.val.string.len);
continue;
}
else if (!(type == WJB_VALUE || type == WJB_ELEM))
{
/* do not call callback for composite JsonbValue */
continue;
}
/* JsonbValue is a value of object or element of array */
switch (v.type)
{
case jbvString:
if (flags & jtiString)
action(state, v.val.string.val, v.val.string.len);
break;
case jbvNumeric:
if (flags & jtiNumeric)
{
char *val;
val = DatumGetCString(DirectFunctionCall1(numeric_out,
NumericGetDatum(v.val.numeric)));
action(state, val, strlen(val));
pfree(val);
}
break;
case jbvBool:
if (flags & jtiBool)
{
if (v.val.boolean)
action(state, "true", 4);
else
action(state, "false", 5);
}
break;
default:
/* do not call callback for composite JsonbValue */
break;
}
}
}
/*
* Iterate over json values and elements, specified by flags, and pass them
* together with an iteration state to a specified JsonIterateStringValuesAction.
*/
void
iterate_json_values(text *json, uint32 flags, void *action_state,
JsonIterateStringValuesAction action)
{
JsonLexContext *lex = makeJsonLexContext(json, true);
JsonSemAction *sem = palloc0(sizeof(JsonSemAction));
IterateJsonStringValuesState *state = palloc0(sizeof(IterateJsonStringValuesState));
state->lex = lex;
state->action = action;
state->action_state = action_state;
state->flags = flags;
sem->semstate = (void *) state;
sem->scalar = iterate_values_scalar;
sem->object_field_start = iterate_values_object_field_start;
pg_parse_json(lex, sem);
}
/*
* An auxiliary function for iterate_json_values to invoke a specified
* JsonIterateStringValuesAction for specified values.
*/
static void
iterate_values_scalar(void *state, char *token, JsonTokenType tokentype)
{
IterateJsonStringValuesState *_state = (IterateJsonStringValuesState *) state;
switch (tokentype)
{
case JSON_TOKEN_STRING:
if (_state->flags & jtiString)
_state->action(_state->action_state, token, strlen(token));
break;
case JSON_TOKEN_NUMBER:
if (_state->flags & jtiNumeric)
_state->action(_state->action_state, token, strlen(token));
break;
case JSON_TOKEN_TRUE:
case JSON_TOKEN_FALSE:
if (_state->flags & jtiBool)
_state->action(_state->action_state, token, strlen(token));
break;
default:
/* do not call callback for any other token */
break;
}
}
static void
iterate_values_object_field_start(void *state, char *fname, bool isnull)
{
IterateJsonStringValuesState *_state = (IterateJsonStringValuesState *) state;
if (_state->flags & jtiKey)
{
char *val = pstrdup(fname);
_state->action(_state->action_state, val, strlen(val));
}
}
/*
* Iterate over a jsonb, and apply a specified JsonTransformStringValuesAction
* to every string value or element. Any necessary context for a
* JsonTransformStringValuesAction can be passed in the action_state variable.
* Function returns a copy of an original jsonb object with transformed values.
*/
Jsonb *
transform_jsonb_string_values(Jsonb *jsonb, void *action_state,
JsonTransformStringValuesAction transform_action)
{
JsonbIterator *it;
JsonbValue v,
*res = NULL;
JsonbIteratorToken type;
JsonbParseState *st = NULL;
text *out;
bool is_scalar = false;
it = JsonbIteratorInit(&jsonb->root);
is_scalar = it->isScalar;
while ((type = JsonbIteratorNext(&it, &v, false)) != WJB_DONE)
{
if ((type == WJB_VALUE || type == WJB_ELEM) && v.type == jbvString)
{
out = transform_action(action_state, v.val.string.val, v.val.string.len);
v.val.string.val = VARDATA_ANY(out);
v.val.string.len = VARSIZE_ANY_EXHDR(out);
res = pushJsonbValue(&st, type, type < WJB_BEGIN_ARRAY ? &v : NULL);
}
else
{
res = pushJsonbValue(&st, type, (type == WJB_KEY ||
type == WJB_VALUE ||
type == WJB_ELEM) ? &v : NULL);
}
}
if (res->type == jbvArray)
res->val.array.rawScalar = is_scalar;
return JsonbValueToJsonb(res);
}
/*
* Iterate over a json, and apply a specified JsonTransformStringValuesAction
* to every string value or element. Any necessary context for a
* JsonTransformStringValuesAction can be passed in the action_state variable.
* Function returns a StringInfo, which is a copy of an original json with
* transformed values.
*/
text *
transform_json_string_values(text *json, void *action_state,
JsonTransformStringValuesAction transform_action)
{
JsonLexContext *lex = makeJsonLexContext(json, true);
JsonSemAction *sem = palloc0(sizeof(JsonSemAction));
TransformJsonStringValuesState *state = palloc0(sizeof(TransformJsonStringValuesState));
state->lex = lex;
state->strval = makeStringInfo();
state->action = transform_action;
state->action_state = action_state;
sem->semstate = (void *) state;
sem->scalar = transform_string_values_scalar;
sem->object_start = transform_string_values_object_start;
sem->object_end = transform_string_values_object_end;
sem->array_start = transform_string_values_array_start;
sem->array_end = transform_string_values_array_end;
sem->scalar = transform_string_values_scalar;
sem->array_element_start = transform_string_values_array_element_start;
sem->object_field_start = transform_string_values_object_field_start;
pg_parse_json(lex, sem);
return cstring_to_text_with_len(state->strval->data, state->strval->len);
}
/*
* Set of auxiliary functions for transform_json_string_values to invoke a
* specified JsonTransformStringValuesAction for all values and left everything
* else untouched.
*/
static void
transform_string_values_object_start(void *state)
{
TransformJsonStringValuesState *_state = (TransformJsonStringValuesState *) state;
appendStringInfoCharMacro(_state->strval, '{');
}
static void
transform_string_values_object_end(void *state)
{
TransformJsonStringValuesState *_state = (TransformJsonStringValuesState *) state;
appendStringInfoCharMacro(_state->strval, '}');
}
static void
transform_string_values_array_start(void *state)
{
TransformJsonStringValuesState *_state = (TransformJsonStringValuesState *) state;
appendStringInfoCharMacro(_state->strval, '[');
}
static void
transform_string_values_array_end(void *state)
{
TransformJsonStringValuesState *_state = (TransformJsonStringValuesState *) state;
appendStringInfoCharMacro(_state->strval, ']');
}
static void
transform_string_values_object_field_start(void *state, char *fname, bool isnull)
{
TransformJsonStringValuesState *_state = (TransformJsonStringValuesState *) state;
if (_state->strval->data[_state->strval->len - 1] != '{')
appendStringInfoCharMacro(_state->strval, ',');
/*
* Unfortunately we don't have the quoted and escaped string any more, so
* we have to re-escape it.
*/
escape_json(_state->strval, fname);
appendStringInfoCharMacro(_state->strval, ':');
}
static void
transform_string_values_array_element_start(void *state, bool isnull)
{
TransformJsonStringValuesState *_state = (TransformJsonStringValuesState *) state;
if (_state->strval->data[_state->strval->len - 1] != '[')
appendStringInfoCharMacro(_state->strval, ',');
}
static void
transform_string_values_scalar(void *state, char *token, JsonTokenType tokentype)
{
TransformJsonStringValuesState *_state = (TransformJsonStringValuesState *) state;
if (tokentype == JSON_TOKEN_STRING)
{
text *out = _state->action(_state->action_state, token, strlen(token));
escape_json(_state->strval, text_to_cstring(out));
}
else
appendStringInfoString(_state->strval, token);
}
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