fix(google): fail over between compatible hosts

src/lib/services/googleTranslate.ts

@@ -40,8 +40,7 @@ export async function translateWithGoogle(
     googleApiUrl.searchParams.append("dt", "t"); // 't' for translation of text
     googleApiUrl.searchParams.append("q", text); // The text to translate
 
-    // Make the fetch call to Google Translate
-    const googleResponse = await fetch(googleApiUrl.toString(), {
+    const requestInit = {
       method: "GET",
       headers: {
         "User-Agent":
@@ -50,11 +49,22 @@ export async function translateWithGoogle(
         "Accept-Language": "en-US,en;q=0.9",
         Referer: "https://translate.google.com/",
       },
-    });
+    };
 
-    if (!googleResponse.ok) {
+    let googleResponse: Response | undefined;
+    for (const hostname of ["translate.googleapis.com", "translate.google.com"]) {
+      googleApiUrl.hostname = hostname;
+      try {
+        googleResponse = await fetch(googleApiUrl.toString(), requestInit);
+        if (googleResponse.ok) break;
+      } catch {
+        // Try the compatible fallback host.
+      }
+    }
+
+    if (!googleResponse?.ok) {
       throw new Error(
-        `Google Translate API responded with status ${googleResponse.status}`
+        `Google Translate API responded with status ${googleResponse?.status || 500}`
       );
     }
 

tests/lib/services/googleTranslate.test.ts

@@ -75,6 +75,30 @@ describe("Google Translate Service", () => {
       expect(result.data).toBeNull();
     });
 
+    it("should use the compatible host when the primary is unavailable", async () => {
+      global.fetch = jest
+        .fn()
+        .mockResolvedValueOnce({ ok: false, status: 429 })
+        .mockResolvedValueOnce({
+          ok: true,
+          json: () =>
+            Promise.resolve([[["Hola", "Hello", null, null, 10]], null, "en"]),
+        });
+
+      const result = await translateWithGoogle({
+        text: "Hello",
+        source_lang: "en",
+        target_lang: "es",
+      });
+
+      expect(result.code).toBe(200);
+      expect(fetch).toHaveBeenCalledTimes(2);
+      expect(fetch).toHaveBeenLastCalledWith(
+        expect.stringContaining("translate.google.com"),
+        expect.any(Object)
+      );
+    });
+
     it("should handle network errors", async () => {
       // Mock fetch for network error
       global.fetch = jest.fn(() =>