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/*
*/
"use strict";
const { SyncWaterfallHook } = require("tapable");
const Compilation = require("../Compilation");
const RuntimeGlobals = require("../RuntimeGlobals");
const RuntimeModule = require("../RuntimeModule");
const Template = require("../Template");
/**
* @typedef {object} ResourceHintRuntimeModulePluginHooks
* @property {SyncWaterfallHook<[string]>} linkPrefetch
* @property {SyncWaterfallHook<[string]>} linkPreload
*/
/** @type {WeakMap<Compilation, ResourceHintRuntimeModulePluginHooks>} */
const compilationHooksMap = new WeakMap();
/**
* Maps a request/filename to the value of the `<link>` `as` attribute. Best
* effort — falls back to `"fetch"` when the type cannot be guessed. Pattern
* matches against the path part, ignoring any query string suffix.
* @param {string} request request/filename
* @returns {string} value for the `as` attribute
*/
const guessAsAttribute = (request) => {
if (/\.(png|jpe?g|gif|svg|webp|avif|bmp|ico|tiff?)(\?.*)?$/i.test(request)) {
return "image";
}
if (/\.(woff2?|ttf|otf|eot)(\?.*)?$/i.test(request)) return "font";
if (/\.css(\?.*)?$/i.test(request)) return "style";
if (/\.[cm]?jsx?(\?.*)?$/i.test(request)) return "script";
if (/\.[cm]?tsx?(\?.*)?$/i.test(request)) return "script";
if (/\.(mp3|wav|flac|aac|m4a|ogg|oga)(\?.*)?$/i.test(request)) return "audio";
if (/\.(mp4|webm|mkv|mov|m4v|ogv|avi)(\?.*)?$/i.test(request)) return "video";
if (/\.vtt(\?.*)?$/i.test(request)) return "track";
return "fetch";
};
class ResourceHintRuntimeModule extends RuntimeModule {
/**
* @param {Compilation} compilation the compilation
* @returns {ResourceHintRuntimeModulePluginHooks} hooks
*/
static getCompilationHooks(compilation) {
if (!(compilation instanceof Compilation)) {
throw new TypeError(
"The 'compilation' argument must be an instance of Compilation"
);
}
let hooks = compilationHooksMap.get(compilation);
if (hooks === undefined) {
hooks = {
linkPrefetch: new SyncWaterfallHook(["source"]),
linkPreload: new SyncWaterfallHook(["source"])
};
compilationHooksMap.set(compilation, hooks);
}
return hooks;
}
/**
* @param {"prefetch" | "preload"} rel link rel value
*/
constructor(rel) {
super(`asset ${rel}`, RuntimeModule.STAGE_ATTACH);
this._rel = rel;
}
/**
* Generates runtime code for this runtime module.
* @returns {string | null} runtime code
*/
generate() {
const compilation = /** @type {Compilation} */ (this.compilation);
const { runtimeTemplate, outputOptions } = compilation;
const { crossOriginLoading } = outputOptions;
const isNeutralPlatform = runtimeTemplate.isNeutralPlatform();
const rel = this._rel;
const fnName =
rel === "prefetch"
? RuntimeGlobals.prefetchAsset
: RuntimeGlobals.preloadAsset;
const hook =
ResourceHintRuntimeModule.getCompilationHooks(compilation)[
rel === "prefetch" ? "linkPrefetch" : "linkPreload"
];
const body = [
"if (installed[href]) return href;",
"installed[href] = 1;",
hook.call(
Template.asString([
"var link = document.createElement('link');",
`link.rel = ${JSON.stringify(rel)};`,
"link.href = href;",
"if (as) link.as = as;",
"if (type) link.type = type;",
"if (media) link.media = media;",
"if (fetchPriority) {",
Template.indent([
'link.setAttribute("fetchpriority", fetchPriority);'
]),
"}",
`if (${RuntimeGlobals.scriptNonce}) {`,
Template.indent(
`link.setAttribute("nonce", ${RuntimeGlobals.scriptNonce});`
),
"}",
crossOriginLoading
? crossOriginLoading === "use-credentials"
? 'link.crossOrigin = "use-credentials";'
: Template.asString([
"if (link.href.indexOf(window.location.origin + '/') !== 0) {",
Template.indent(
`link.crossOrigin = ${JSON.stringify(crossOriginLoading)};`
),
"}"
])
: ""
])
),
"document.head.appendChild(link);",
"return href;"
];
const fnBody = isNeutralPlatform
? ["if (typeof document === 'undefined') return href;", ...body]
: body;
// `Object.create(null)` keeps the dedupe map free of inherited
// properties (`toString`, `__proto__`, …) so any URL string is a
// safe key.
return Template.asString([
"var installed = Object.create(null);",
`${fnName} = ${runtimeTemplate.basicFunction(
"href, as, type, media, fetchPriority",
fnBody
)};`
]);
}
}
ResourceHintRuntimeModule.guessAsAttribute = guessAsAttribute;
module.exports = ResourceHintRuntimeModule;