webpack/lib/JsonGenerator.js

90 lines
2.5 KiB
JavaScript

/*
MIT License http://www.opensource.org/licenses/mit-license.php
Author Tobias Koppers @sokra
*/
"use strict";
const { ConcatSource, RawSource } = require("webpack-sources");
const Generator = require("./Generator");
const RuntimeGlobals = require("./RuntimeGlobals");
/** @typedef {import("webpack-sources").Source} Source */
/** @typedef {import("./Generator").GenerateContext} GenerateContext */
/** @typedef {import("./NormalModule")} NormalModule */
const stringifySafe = data => {
const stringified = JSON.stringify(data);
if (!stringified) {
return undefined; // Invalid JSON
}
return stringified.replace(
/\u2028|\u2029/g,
str => (str === "\u2029" ? "\\u2029" : "\\u2028")
); // invalid in JavaScript but valid JSON
};
const TYPES = new Set(["javascript"]);
class JsonGenerator extends Generator {
/**
* @returns {Set<string>} available types (do not mutate)
*/
getTypes() {
return TYPES;
}
/**
* @param {NormalModule} module the module
* @param {string=} type source type
* @returns {number} estimate size of the module
*/
getSize(module, type) {
let data = module.buildInfo.jsonData;
if (!data) return 0;
return stringifySafe(data).length + 10;
}
/**
* @param {NormalModule} module module for which the code should be generated
* @param {GenerateContext} generateContext context for generate
* @returns {Source} generated code
*/
generate(module, { moduleGraph, runtimeTemplate, runtimeRequirements }) {
const source = new ConcatSource();
const data = module.buildInfo.jsonData;
if (data === undefined) {
return new RawSource(
runtimeTemplate.missingModuleStatement({
request: module.rawRequest
})
);
}
runtimeRequirements.add(RuntimeGlobals.module);
const providedExports = moduleGraph.getProvidedExports(module);
if (
Array.isArray(providedExports) &&
!module.isExportUsed(moduleGraph, "default")
) {
// Only some exports are used: We can optimize here, by only generating a part of the JSON
const reducedJson = {};
for (const exportName of providedExports) {
if (exportName === "default") continue;
const used = module.getUsedName(moduleGraph, exportName);
if (typeof used === "string") {
reducedJson[used] = data[exportName];
}
}
source.add(
`${module.moduleArgument}.exports = ${stringifySafe(reducedJson)};`
);
} else {
source.add(`${module.moduleArgument}.exports = ${stringifySafe(data)};`);
}
return source;
}
}
module.exports = JsonGenerator;