feat: add beforeTagInsert hook

.cspell.json

@@ -30,7 +30,8 @@
     "vspace",
     "commitlint",
     "unreload",
-    "cnfg"
+    "cnfg",
+    "tapable"
   ],
 
   "ignorePaths": [

README.md

@@ -1194,6 +1194,27 @@ If you'd like to extract the media queries from the extracted CSS (so mobile use
 - [Media Query Plugin](https://github.com/SassNinja/media-query-plugin)
 - [Media Query Splitting Plugin](https://github.com/mike-diamond/media-query-splitting-plugin)
 
+## Hooks
+
+The mini-css-extract-plugin provides hooks to extend it to your needs.
+
+### beforeTagInsert
+
+`SyncWaterfallHook`
+
+Called before inject the insert code for link tag. Should return a string
+
+```javascript
+MiniCssExtractPlugin.getCompilationHooks(compilation).beforeTagInsert.tap(
+  "changeHref",
+  (source, varNames) =>
+    Template.asString([
+      source,
+      `${varNames.tag}.setAttribute("href", "https://github.com/webpack-contrib/mini-css-extract-plugin");`,
+    ])
+);
+```
+
 ## Contributing
 
 Please take a moment to read our contributing guidelines if you haven't yet done so.

package.json

@@ -52,7 +52,8 @@
     "webpack": "^5.0.0"
   },
   "dependencies": {
-    "schema-utils": "^4.0.0"
+    "schema-utils": "^4.0.0",
+    "tapable": "^2.2.1"
   },
   "devDependencies": {
     "@babel/cli": "^7.21.0",

src/hooks.js

@@ -0,0 +1,35 @@
+const { SyncWaterfallHook } = require("tapable");
+
+/** @typedef {import("webpack").Compilation} Compilation */
+/**
+ * @typedef {Object} VarNames
+ * @property {string} tag
+ * @property {string} chunkId
+ * @property {string} href
+ * @property {string} resolve
+ * @property {string} reject
+ */
+
+/**
+ * @typedef {Object} MiniCssExtractPluginCompilationHooks
+ * @property {import("tapable").SyncWaterfallHook<[string, VarNames], string>} beforeTagInsert
+ */
+
+/** @type {WeakMap<Compilation, MiniCssExtractPluginCompilationHooks>} */
+const compilationHooksMap = new WeakMap();
+
+/**
+ *
+ * @param {Compilation} compilation the compilation
+ * @returns {MiniCssExtractPluginCompilationHooks} the compilation hooks
+ */
+exports.getCompilationHooks = function getCompilationHooks(compilation) {
+  let hooks = compilationHooksMap.get(compilation);
+  if (!hooks) {
+    hooks = {
+      beforeTagInsert: new SyncWaterfallHook(["source", "varNames"], "string"),
+    };
+    compilationHooksMap.set(compilation, hooks);
+  }
+  return hooks;
+};

src/index.js

@@ -15,6 +15,7 @@ const {
   getUndoPath,
   BASE_URI,
 } = require("./utils");
+const { getCompilationHooks } = require("./hooks");
 
 /** @typedef {import("schema-utils/declarations/validate").Schema} Schema */
 /** @typedef {import("webpack").Compiler} Compiler */
@@ -513,6 +514,14 @@ class MiniCssExtractPlugin {
     return CssDependency;
   }
 
+  /**
+   * Returns all hooks for the given compilation
+   * @param {Compilation} compilation
+   */
+  static getCompilationHooks(compilation) {
+    return getCompilationHooks(compilation);
+  }
+
   /**
    * @param {PluginOptions} [options]
    */
@@ -843,7 +852,6 @@ class MiniCssExtractPlugin {
           if (!withLoading && !withHmr) {
             return "";
           }
-
           return Template.asString([
             'if (typeof document === "undefined") return;',
             `var createStylesheet = ${runtimeTemplate.basicFunction(
@@ -902,6 +910,15 @@ class MiniCssExtractPlugin {
                       "}",
                     ])
                   : "",
+                MiniCssExtractPlugin.getCompilationHooks(
+                  compilation
+                ).beforeTagInsert.call("", {
+                  tag: "linkTag",
+                  chunkId: "chunkId",
+                  href: "fullhref",
+                  resolve: "resolve",
+                  reject: "reject",
+                }) || "",
                 typeof this.runtimeOptions.insert !== "undefined"
                   ? typeof this.runtimeOptions.insert === "function"
                     ? `(${this.runtimeOptions.insert.toString()})(linkTag)`

test/cases/chunkFilename-fullhash/expected/webpack-5-importModule/main.js

@@ -73,7 +73,7 @@ __webpack_require__.r(__webpack_exports__);
 /******/ 	
 /******/ 	/* webpack/runtime/getFullHash */
 /******/ 	(() => {
-/******/ 		__webpack_require__.h = () => ("7f0e5fa686a9bb728e64")
+/******/ 		__webpack_require__.h = () => ("04f5273a6b9819ed9e63")
 /******/ 	})();
 /******/ 	
 /******/ 	/* webpack/runtime/global */
@@ -201,6 +201,7 @@ __webpack_require__.r(__webpack_exports__);
 /******/ 			linkTag.onerror = linkTag.onload = onLinkComplete;
 /******/ 			linkTag.href = fullhref;
 /******/ 		
+/******/ 		
 /******/ 			if (oldTag) {
 /******/ 				oldTag.parentNode.insertBefore(linkTag, oldTag.nextSibling);
 /******/ 			} else {

test/cases/chunkFilename-fullhash/expected/webpack-5/main.js

@@ -73,7 +73,7 @@ __webpack_require__.r(__webpack_exports__);
 /******/ 	
 /******/ 	/* webpack/runtime/getFullHash */
 /******/ 	(() => {
-/******/ 		__webpack_require__.h = () => ("100253bb7576627988e6")
+/******/ 		__webpack_require__.h = () => ("04f5273a6b9819ed9e63")
 /******/ 	})();
 /******/ 	
 /******/ 	/* webpack/runtime/global */
@@ -201,6 +201,7 @@ __webpack_require__.r(__webpack_exports__);
 /******/ 			linkTag.onerror = linkTag.onload = onLinkComplete;
 /******/ 			linkTag.href = fullhref;
 /******/ 		
+/******/ 		
 /******/ 			if (oldTag) {
 /******/ 				oldTag.parentNode.insertBefore(linkTag, oldTag.nextSibling);
 /******/ 			} else {

test/cases/hmr/expected/main.js

@@ -964,6 +964,7 @@ __webpack_require__.r(__webpack_exports__);
 /******/ 			linkTag.onerror = linkTag.onload = onLinkComplete;
 /******/ 			linkTag.href = fullhref;
 /******/ 		
+/******/ 		
 /******/ 			if (oldTag) {
 /******/ 				oldTag.parentNode.insertBefore(linkTag, oldTag.nextSibling);
 /******/ 			} else {

test/cases/insert-function/expected/main.js

@@ -185,6 +185,7 @@
 /******/ 			linkTag.onerror = linkTag.onload = onLinkComplete;
 /******/ 			linkTag.href = fullhref;
 /******/ 		
+/******/ 		
 /******/ 			(function (linkTag) {
 /******/ 			      const reference = document.querySelector(".hot-reload");
 /******/ 			      if (reference) {

test/cases/insert-string/expected/main.js

@@ -185,6 +185,7 @@
 /******/ 			linkTag.onerror = linkTag.onload = onLinkComplete;
 /******/ 			linkTag.href = fullhref;
 /******/ 		
+/******/ 		
 /******/ 			var target = document.querySelector("script[src='1.js']");
 /******/ 			target.parentNode.insertBefore(linkTag, target.nextSibling);
 /******/ 			return linkTag;

test/cases/insert-undefined/expected/main.js

@@ -185,6 +185,7 @@
 /******/ 			linkTag.onerror = linkTag.onload = onLinkComplete;
 /******/ 			linkTag.href = fullhref;
 /******/ 		
+/******/ 		
 /******/ 			if (oldTag) {
 /******/ 				oldTag.parentNode.insertBefore(linkTag, oldTag.nextSibling);
 /******/ 			} else {

test/hooks.test.js

@@ -0,0 +1,74 @@
+/* eslint-env browser */
+import path from "path";
+
+import { Template } from "webpack";
+
+import MiniCssExtractPlugin from "../src";
+
+import { runInJsDom, compile, getCompiler } from "./helpers/index";
+
+describe("hooks", () => {
+  it(`beforeTagInsert`, async () => {
+    const webpackCompiler = getCompiler(
+      "insert.js",
+      {},
+      {
+        mode: "none",
+        output: {
+          publicPath: "",
+          path: path.resolve(__dirname, "../outputs"),
+          filename: "[name].bundle.js",
+        },
+        plugins: [
+          new MiniCssExtractPlugin({
+            filename: "[name].css",
+          }),
+          {
+            /**
+             *
+             * @param {import('webpack').Compiler} compiler
+             */
+            apply: (compiler) => {
+              compiler.hooks.compilation.tap("sri", (compilation) => {
+                MiniCssExtractPlugin.getCompilationHooks(
+                  compilation
+                ).beforeTagInsert.tap("sri", (source, varNames) =>
+                  Template.asString([
+                    source,
+                    `${varNames.tag}.setAttribute("integrity", "sriHashes[${varNames.chunkId}]");`,
+                  ])
+                );
+              });
+            },
+          },
+          {
+            /**
+             *
+             * @param {import('webpack').Compiler} compiler
+             */
+            apply: (compiler) => {
+              compiler.hooks.compilation.tap("href", (compilation) => {
+                MiniCssExtractPlugin.getCompilationHooks(
+                  compilation
+                ).beforeTagInsert.tap("changeHref", (source, varNames) =>
+                  Template.asString([
+                    source,
+                    `${varNames.tag}.setAttribute("href", "https://github.com/webpack-contrib/mini-css-extract-plugin");`,
+                  ])
+                );
+              });
+            },
+          },
+        ],
+      }
+    );
+    const stats = await compile(webpackCompiler);
+    runInJsDom("main.bundle.js", webpackCompiler, stats, (dom) => {
+      const [tag] = dom.window.document.head.getElementsByTagName("link");
+      expect(tag.getAttribute("integrity")).toBe("sriHashes[chunkId]");
+      expect(tag.getAttribute("href")).toBe(
+        "https://github.com/webpack-contrib/mini-css-extract-plugin"
+      );
+    });
+  });
+});

types/hooks.d.ts

@@ -0,0 +1,17 @@
+export function getCompilationHooks(
+  compilation: Compilation
+): MiniCssExtractPluginCompilationHooks;
+export type Compilation = import("webpack").Compilation;
+export type VarNames = {
+  tag: string;
+  chunkId: string;
+  href: string;
+  resolve: string;
+  reject: string;
+};
+export type MiniCssExtractPluginCompilationHooks = {
+  beforeTagInsert: import("tapable").SyncWaterfallHook<
+    [string, VarNames],
+    string
+  >;
+};

types/index.d.ts

@@ -12,6 +12,13 @@ declare class MiniCssExtractPlugin {
   static getCssDependency(
     webpack: Compiler["webpack"]
   ): CssDependencyConstructor;
+  /**
+   * Returns all hooks for the given compilation
+   * @param {Compilation} compilation
+   */
+  static getCompilationHooks(
+    compilation: Compilation
+  ): import("./hooks").MiniCssExtractPluginCompilationHooks;
   /**
    * @param {PluginOptions} [options]
    */
@@ -103,6 +110,7 @@ type CssDependencyConstructor = new (
   context: string | null,
   identifierIndex: number
 ) => CssDependency;
+type Compilation = import("webpack").Compilation;
 type PluginOptions = {
   filename?: Required<Configuration>["output"]["filename"];
   chunkFilename?: Required<Configuration>["output"]["chunkFilename"];
@@ -166,7 +174,6 @@ declare const pluginName: "mini-css-extract-plugin";
 declare const pluginSymbol: unique symbol;
 declare var loader: string;
 type Schema = import("schema-utils/declarations/validate").Schema;
-type Compilation = import("webpack").Compilation;
 type ChunkGraph = import("webpack").ChunkGraph;
 type Chunk = import("webpack").Chunk;
 type ChunkGroup = Parameters<import("webpack").Chunk["isInGroup"]>[0];