hugo/resources/resource_transformers/templates/execute_as_template.go

75 lines
2.4 KiB
Go

// Copyright 2018 The Hugo Authors. All rights reserved.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Package templates contains functions for template processing of Resource objects.
package templates
import (
"github.com/gohugoio/hugo/helpers"
"github.com/gohugoio/hugo/resources"
"github.com/gohugoio/hugo/resources/internal"
"github.com/gohugoio/hugo/resources/resource"
"github.com/gohugoio/hugo/tpl"
"github.com/pkg/errors"
)
// Client contains methods to perform template processing of Resource objects.
type Client struct {
rs *resources.Spec
textTemplate tpl.TemplateParseFinder
}
// New creates a new Client with the given specification.
func New(rs *resources.Spec, textTemplate tpl.TemplateParseFinder) *Client {
if rs == nil {
panic("must provice a resource Spec")
}
if textTemplate == nil {
panic("must provide a textTemplate")
}
return &Client{rs: rs, textTemplate: textTemplate}
}
type executeAsTemplateTransform struct {
rs *resources.Spec
textTemplate tpl.TemplateParseFinder
targetPath string
data interface{}
}
func (t *executeAsTemplateTransform) Key() internal.ResourceTransformationKey {
return internal.NewResourceTransformationKey("execute-as-template", t.targetPath)
}
func (t *executeAsTemplateTransform) Transform(ctx *resources.ResourceTransformationCtx) error {
tplStr := helpers.ReaderToString(ctx.From)
templ, err := t.textTemplate.Parse(ctx.InPath, tplStr)
if err != nil {
return errors.Wrapf(err, "failed to parse Resource %q as Template:", ctx.InPath)
}
ctx.OutPath = t.targetPath
return templ.Execute(ctx.To, t.data)
}
func (c *Client) ExecuteAsTemplate(res resources.ResourceTransformer, targetPath string, data interface{}) (resource.Resource, error) {
return res.Transform(&executeAsTemplateTransform{
rs: c.rs,
targetPath: helpers.ToSlashTrimLeading(targetPath),
textTemplate: c.textTemplate,
data: data,
})
}