nuxt-i18n-micro/dist/runtime/server/routes/get.js

Nuxt I18n Micro is a lightweight, high-performance internationalization module for Nuxt, designed to handle multi-language support with minimal overhead, fast build times, and efficient runtime performance.

import { resolve } from "node:path";
import { readFile } from "node:fs/promises";
import { defineEventHandler, setResponseHeader } from "h3";
import { useRuntimeConfig, createError, useStorage } from "#imports";
let storageInit = false;
function deepMerge(target, source) {
  const output = { ...target };
  for (const key in source) {
    if (key === "__proto__" || key === "constructor") continue;
    const src = source[key];
    const dst = output[key];
    if (src && typeof src === "object" && !Array.isArray(src) && dst && typeof dst === "object" && !Array.isArray(dst)) {
      output[key] = deepMerge(dst, src);
    } else {
      output[key] = src;
    }
  }
  return output;
}
async function readTranslationFile(filePath, debug) {
  try {
    const content = await readFile(filePath, "utf-8");
    return JSON.parse(content);
  } catch (e) {
    if (debug && e?.code !== "ENOENT") {
      console.error(`[i18n] Error loading locale file: ${filePath}`, e);
    }
    return null;
  }
}
export default defineEventHandler(async (event) => {
  setResponseHeader(event, "Content-Type", "application/json");
  const { page, locale } = event.context.params;
  const config = useRuntimeConfig();
  const { rootDirs, debug, translationDir, fallbackLocale, routesLocaleLinks } = config.i18nConfig;
  const { locales } = config.public.i18nConfig;
  if (locales && !locales.map((l) => l.code).includes(locale)) {
    throw createError({ statusCode: 404 });
  }
  let fileLookupPage = page;
  if (routesLocaleLinks && page && routesLocaleLinks[page]) {
    fileLookupPage = routesLocaleLinks[page] || page;
    if (debug) {
      console.log(`[i18n] Route link found: '${page}' -> '${fileLookupPage}'. Using linked translations.`);
    }
  }
  const serverStorage = useStorage("assets:server");
  const cacheKey = `_locales:merged:${page}:${locale}`;
  if (!storageInit) {
    if (debug) console.log("[nuxt-i18n-micro] clear storage cache");
    await Promise.all((await serverStorage.getKeys("_locales")).map((key) => serverStorage.removeItem(key)));
    storageInit = true;
  }
  const cachedMerged = await serverStorage.getItem(cacheKey);
  if (cachedMerged) {
    return cachedMerged;
  }
  const getPathsFor = (targetLocale, targetPage) => rootDirs.map((dir) => resolve(dir, translationDir, targetPage === "general" ? `${targetLocale}.json` : `pages/${targetPage}/${targetLocale}.json`));
  let finalTranslations = {};
  const currentLocaleConfig = locales?.find((l) => l.code === locale) ?? null;
  const loadAndMerge = async (targetLocale) => {
    let globalTranslations = {};
    let pageTranslations = {};
    for (const p of getPathsFor(targetLocale, "general")) {
      const content = await readTranslationFile(p, debug);
      if (content) globalTranslations = deepMerge(globalTranslations, content);
    }
    if (page !== "general") {
      for (const p of getPathsFor(targetLocale, fileLookupPage)) {
        const content = await readTranslationFile(p, debug);
        if (content) pageTranslations = deepMerge(pageTranslations, content);
      }
    }
    return deepMerge(globalTranslations, pageTranslations);
  };
  const fallbackLocalesList = [
    fallbackLocale,
    currentLocaleConfig?.fallbackLocale
  ].filter((l) => !!l && l !== locale);
  for (const fb of [...new Set(fallbackLocalesList)]) {
    const fbTranslations = await loadAndMerge(fb);
    finalTranslations = deepMerge(finalTranslations, fbTranslations);
  }
  const mainTranslations = await loadAndMerge(locale);
  finalTranslations = deepMerge(finalTranslations, mainTranslations);
  await serverStorage.setItem(cacheKey, finalTranslations);
  return finalTranslations;
});