feat: create translatorMiddleware

src/middleware/translatorMiddleware.ts

@@ -0,0 +1,33 @@
+import { AppMiddleware } from '@/app.ts';
+import { Conf } from '@/config.ts';
+import { fetchWorker } from '@/workers/fetch.ts';
+import { DeepLTranslator } from '@/translators/DeepLTranslator.ts';
+import { LibreTranslateTranslator } from '@/translators/LibreTranslateTranslator.ts';
+
+/** Set the translator used for translating posts. */
+export const translatorMiddleware: AppMiddleware = async (c, next) => {
+  const endpoint = Conf.translationProviderEndpoint;
+  const apiKey = Conf.translationProviderApiKey;
+  const translationProvider = Conf.translationProvider;
+
+  switch (translationProvider) {
+    case 'DeepL'.toLowerCase():
+      if (apiKey) {
+        c.set(
+          'translator',
+          new DeepLTranslator({ endpoint, apiKey, fetch: fetchWorker }),
+        );
+      }
+      break;
+    case 'Libretranslate'.toLowerCase():
+      if (apiKey) {
+        c.set(
+          'translator',
+          new LibreTranslateTranslator({ endpoint, apiKey, fetch: fetchWorker }),
+        );
+      }
+      break;
+  }
+
+  await next();
+};