Rewrite copy-res i18n build as a webpack plugin (#32664)

* Replace copy-res with a webpack plugin Signed-off-by: Michael Telatynski <7t3chguy@gmail.com> * Specify writeToDisk=true for webpack-dev-server Signed-off-by: Michael Telatynski <7t3chguy@gmail.com> * Use async fs methods Signed-off-by: Michael Telatynski <7t3chguy@gmail.com> --------- Signed-off-by: Michael Telatynski <7t3chguy@gmail.com>
2026-02-27 13:00:25 +00:00
parent 89fb388e57
commit 0a308743b8
6 changed files with 131 additions and 199 deletions
@@ -0,0 +1,123 @@
+/*
+Copyright 2026 Element Creations Ltd.
+
+SPDX-License-Identifier: AGPL-3.0-only OR GPL-3.0-only OR LicenseRef-Element-Commercial
+Please see LICENSE files in the repository root for full details.
+*/
+
+import webpack from "webpack";
+import * as fs from "node:fs/promises";
+import * as path from "node:path";
+import _ from "lodash";
+import { type Translations } from "matrix-web-i18n";
+
+interface Options {
+    // Path to the strings for the application, will be used to deduce what languages are supported
+    stringsPath: string;
+    // Additional paths to strings which will be merged into the application's own strings for supported languages
+    additionalStringsPaths?: string[];
+}
+
+async function exists(path: string): Promise<boolean> {
+    try {
+        await fs.access(path);
+        return true;
+    } catch {
+        return false;
+    }
+}
+
+export class I18nWebpackPlugin {
+    private readonly options: Options;
+
+    public constructor(options: Options) {
+        this.options = options;
+    }
+
+    public apply(compiler: webpack.Compiler): void {
+        const { RawSource } = compiler.webpack.sources;
+
+        compiler.hooks.thisCompilation.tap("I18nWebpackPlugin", (compilation) => {
+            compilation.hooks.processAssets.tapPromise(
+                {
+                    name: "I18nWebpackPlugin",
+                    stage: webpack.Compilation.PROCESS_ASSETS_STAGE_ADDITIONS,
+                },
+                async () => {
+                    const paths = [this.options.stringsPath, ...(this.options.additionalStringsPaths ?? [])].map((p) =>
+                        path.resolve(compiler.context, p),
+                    );
+
+                    const logger = compilation.getLogger("I18nWebpackPlugin");
+
+                    for (const p of paths) {
+                        compilation.contextDependencies.add(p);
+
+                        if (!(await exists(p))) {
+                            compilation.errors.push(
+                                new webpack.WebpackError(`I18nWebpackPlugin: strings path not found: ${p}`),
+                            );
+                            return;
+                        }
+                    }
+
+                    const primaryPath = paths[0];
+                    const includeLangs = [...new Set([...(await fs.readdir(primaryPath))])]
+                        .filter((fn) => fn.endsWith(".json"))
+                        .map((f) => f.slice(0, -5));
+
+                    const langFileMap: Record<string, string> = {};
+
+                    for (const lang of includeLangs) {
+                        let translations: Translations = {};
+                        for (const p of paths) {
+                            const f = path.join(p, lang + ".json");
+
+                            if (await exists(f)) {
+                                try {
+                                    const content = await fs.readFile(f, "utf-8");
+                                    translations = _.merge(translations, JSON.parse(content));
+                                    compilation.fileDependencies.add(f);
+                                } catch (e) {
+                                    compilation.errors.push(
+                                        new webpack.WebpackError(
+                                            `I18nWebpackPlugin: Failed to read or parse ${f}: ${e}`,
+                                        ),
+                                    );
+                                }
+                            }
+                        }
+
+                        const json = JSON.stringify(translations, null, 4);
+                        const jsonBuffer = Buffer.from(json);
+                        const digest = compiler.webpack.util
+                            .createHash("xxhash64")
+                            .update(jsonBuffer)
+                            .digest("hex")
+                            .slice(0, 7);
+                        const filename = `${lang}.${digest}.json`;
+
+                        compilation.emitAsset(`i18n/${filename}`, new RawSource(jsonBuffer));
+                        langFileMap[lang] = filename;
+                        logger.debug(`Generated language file: ${filename}`);
+                    }
+
+                    // Generate languages.json
+                    const languages: Record<string, string> = {};
+                    includeLangs.forEach((lang) => {
+                        const normalizedLanguage = lang.toLowerCase().replace("_", "-");
+                        const languageParts = normalizedLanguage.split("-");
+                        if (languageParts.length == 2 && languageParts[0] == languageParts[1]) {
+                            languages[languageParts[0]] = langFileMap[lang];
+                        } else {
+                            languages[normalizedLanguage] = langFileMap[lang];
+                        }
+                    });
+
+                    compilation.emitAsset("i18n/languages.json", new RawSource(JSON.stringify(languages, null, 4)));
+                    logger.info("Generated languages.json and language files");
+                },
+            );
+        });
+    }
+}