I18N: Collect stats on number of untranslated strings in message catalogues (#76272)

* I18N: Collect stats on number of untranslated strings in message catalogues

* eachLeaf -> eachMessage

* use __dirname

package.json

@@ -49,6 +49,7 @@
     "i18n:extract": "yarn run i18next -c public/locales/i18next-parser.config.js 'public/**/*.{tsx,ts}' 'packages/grafana-ui/**/*.{tsx,ts}' && yarn i18n:pseudo",
     "i18n:compile": "echo 'no i18n compile yet, all good'",
     "i18n:pseudo": "node ./public/locales/pseudo.js",
+    "i18n:stats": "node ./scripts/cli/reportI18nStats.mjs",
     "betterer": "betterer",
     "betterer:merge": "betterer merge",
     "betterer:stats": "ts-node --transpile-only --project ./scripts/cli/tsconfig.json ./scripts/cli/reportBettererStats.ts",

scripts/ci-frontend-metrics.sh

@@ -46,6 +46,13 @@ do
   BETTERER_STATS+="\"grafana.ci-code.betterer.${name}\": \"${value}\","
 done <<< "$(yarn betterer:stats)"
 
+I18N_STATS=""
+while read -r name value
+do
+  I18N_STATS+=$'\n  '
+  I18N_STATS+="\"grafana.ci-code.i18n.${name}\": \"${value}\","
+done <<< "$(yarn i18n:stats)"
+
 THEME_TOKEN_USAGE=""
 while read -r name value
 do
@@ -56,6 +63,7 @@ done <<< "$(yarn themes:usage | awk '$4 == "@grafana/theme-token-usage" {print $
 echo "Metrics: {
   $THEME_TOKEN_USAGE
   $BETTERER_STATS
+  $I18N_STATS
   \"grafana.ci-code.strictErrors\": \"${ERROR_COUNT}\",
   \"grafana.ci-code.accessibilityErrors\": \"${ACCESSIBILITY_ERRORS}\",
   \"grafana.ci-code.directives\": \"${DIRECTIVES}\",

scripts/cli/reportI18nStats.mjs

@@ -0,0 +1,88 @@
+/// @ts-check
+
+import { readdir, stat, readFile } from 'fs/promises';
+import path, { dirname } from 'path';
+import { fileURLToPath } from 'url';
+
+const LOCALES_DIR = path.resolve(dirname(fileURLToPath(import.meta.url)), '..', '..', 'public', 'locales');
+
+const locales = await readdir(LOCALES_DIR);
+
+/**
+ * @type {Array<{ language: string, untranslatedCount: number, translatedCount: number }>}
+ */
+const stats = [];
+
+for (const fileName of locales) {
+  const filePath = path.join(LOCALES_DIR, fileName, 'grafana.json');
+  if (!(await exists(filePath))) {
+    continue;
+  }
+
+  const messages = await readFile(filePath);
+  const parsedMessages = JSON.parse(messages.toString());
+
+  let translatedCount = 0;
+  let untranslatedCount = 0;
+
+  eachMessage(parsedMessages, (value) => {
+    if (value === '') {
+      untranslatedCount += 1;
+    } else {
+      translatedCount += 1;
+    }
+  });
+
+  stats.push({
+    language: fileName,
+    translatedCount,
+    untranslatedCount,
+  });
+}
+
+for (const stat of stats) {
+  logStat(`untranslated.${stat.language}`, stat.untranslatedCount);
+  logStat(`translated.${stat.language}`, stat.translatedCount);
+}
+
+/**
+ * @param {string} filePath
+ */
+async function exists(filePath) {
+  try {
+    await stat(filePath);
+    return true;
+  } catch (err) {
+    if (err.code === 'ENOENT' || err.code === 'ENOTDIR') {
+      return false;
+    }
+    throw err;
+  }
+}
+
+/**
+ * @param {unknown} value
+ * @param {(v: string) => void} callback
+ */
+function eachMessage(value, callback) {
+  if (typeof value === 'object') {
+    for (const key in value) {
+      const element = value[key];
+      eachMessage(element, callback);
+    }
+  } else if (typeof value === 'string') {
+    callback(value);
+  } else {
+    throw new Error(`Unknown value ${value} in eachMessage`);
+  }
+}
+
+/**
+ * @param {string} name
+ * @param {string | number} value
+ */
+function logStat(name, value) {
+  // Note that this output format must match the parsing in ci-frontend-metrics.sh
+  // which expects the two values to be separated by a space
+  console.log(`${name} ${value}`);
+}