webpack/lib/hmr/lazyCompilationBackend.js

135 lines
4.1 KiB
JavaScript

/*
MIT License http://www.opensource.org/licenses/mit-license.php
Author Tobias Koppers @sokra
*/
"use strict";
/** @typedef {import("http").ServerOptions} HttpServerOptions */
/** @typedef {import("https").ServerOptions} HttpsServerOptions */
/** @typedef {import("../../declarations/WebpackOptions").LazyCompilationDefaultBackendOptions} LazyCompilationDefaultBackendOptions */
/** @typedef {import("../Compiler")} Compiler */
/**
* @callback BackendHandler
* @param {Compiler} compiler compiler
* @param {function(Error?, any?): void} callback callback
* @returns {void}
*/
/**
* @param {Omit<LazyCompilationDefaultBackendOptions, "client"> & { client: NonNullable<LazyCompilationDefaultBackendOptions["client"]>}} options additional options for the backend
* @returns {BackendHandler} backend
*/
module.exports = options => (compiler, callback) => {
const logger = compiler.getInfrastructureLogger("LazyCompilationBackend");
const activeModules = new Map();
const prefix = "/lazy-compilation-using-";
const isHttps =
options.protocol === "https" ||
(typeof options.server === "object" &&
("key" in options.server || "pfx" in options.server));
const createServer =
typeof options.server === "function"
? options.server
: (() => {
const http = isHttps ? require("https") : require("http");
return http.createServer.bind(http, options.server);
})();
const listen =
typeof options.listen === "function"
? options.listen
: server => server.listen(options.listen);
const protocol = options.protocol || (isHttps ? "https" : "http");
const requestListener = (req, res) => {
const keys = req.url.slice(prefix.length).split("@");
req.socket.on("close", () => {
setTimeout(() => {
for (const key of keys) {
const oldValue = activeModules.get(key) || 0;
activeModules.set(key, oldValue - 1);
if (oldValue === 1) {
logger.log(
`${key} is no longer in use. Next compilation will skip this module.`
);
}
}
}, 120000);
});
req.socket.setNoDelay(true);
res.writeHead(200, {
"content-type": "text/event-stream",
"Access-Control-Allow-Origin": "*"
});
res.write("\n");
let moduleActivated = false;
for (const key of keys) {
const oldValue = activeModules.get(key) || 0;
activeModules.set(key, oldValue + 1);
if (oldValue === 0) {
logger.log(`${key} is now in use and will be compiled.`);
moduleActivated = true;
}
}
if (moduleActivated && compiler.watching) compiler.watching.invalidate();
};
const server = /** @type {import("net").Server} */ (createServer());
server.on("request", requestListener);
let isClosing = false;
/** @type {Set<import("net").Socket>} */
const sockets = new Set();
server.on("connection", socket => {
sockets.add(socket);
socket.on("close", () => {
sockets.delete(socket);
});
if (isClosing) socket.destroy();
});
server.on("clientError", e => logger.warn(e));
server.on("listening", err => {
if (err) return callback(err);
const addr = server.address();
if (typeof addr === "string") throw new Error("addr must not be a string");
const urlBase =
addr.address === "::" || addr.address === "0.0.0.0"
? `${protocol}://localhost:${addr.port}`
: addr.family === "IPv6"
? `${protocol}://[${addr.address}]:${addr.port}`
: `${protocol}://${addr.address}:${addr.port}`;
logger.log(
`Server-Sent-Events server for lazy compilation open at ${urlBase}.`
);
callback(null, {
dispose(callback) {
isClosing = true;
// Removing the listener is a workaround for a memory leak in node.js
server.off("request", requestListener);
server.close(err => {
callback(err);
});
for (const socket of sockets) {
socket.destroy(new Error("Server is disposing"));
}
},
module(originalModule) {
const key = `${encodeURIComponent(
originalModule.identifier().replace(/\\/g, "/").replace(/@/g, "_")
).replace(/%(2F|3A|24|26|2B|2C|3B|3D|3A)/g, decodeURIComponent)}`;
const active = activeModules.get(key) > 0;
return {
client: `${options.client}?${encodeURIComponent(urlBase + prefix)}`,
data: key,
active
};
}
});
});
listen(server);
};