Update app.py

app.py

@@ -73,6 +73,19 @@ def fetch_sheet_rows_and_pronunciations(retries=5, delay=3):
         except Exception as e:
             time.sleep(delay)
     return [], {}
+
+def call_tts(client, chunk, voice, rate, pitch):
+    """Try TTS with retries + fallback signature."""
+    for attempt in range(3):
+        try:
+            try:
+                return client.predict(chunk, voice, rate, pitch, api_name="/tts_interface")
+            except Exception:
+                # Some Spaces only accept (text, voice)
+                return client.predict(chunk, voice, api_name="/tts_interface")
+        except Exception:
+            time.sleep(1.2 * (attempt + 1))
+    raise RuntimeError("Upstream TTS failed after retries")
     
 # REPLACE your existing /tts with this
 @app.route("/tts", methods=["POST"])
@@ -90,37 +103,48 @@ def tts():
     rate  = max(-50, min(50, rate))
     pitch = max(-20, min(20, pitch))
 
-    # 9k-char chunks to beat ~10-min timeouts
-    parts = chunk_text(text_input, 9000)
+    # smaller chunks for stability
+    parts = chunk_text(text_input, 1800)
 
-    # your existing HF client base stays the same
     client = Client("https://altafo-free-tts-unlimted-words.hf.space/")
 
     os.makedirs("static", exist_ok=True)
     out_name = f"{uuid.uuid4().hex}.mp3"
     out_path = os.path.join("static", out_name)
 
-    # single-shot path (no merge)
+    # single-chunk fast path
     if len(parts) == 1:
-        result = client.predict(parts[0], voice, rate, pitch, api_name="/tts_interface")
+        try:
+            result = call_tts(client, parts[0], voice, rate, pitch)
+        except Exception as e:
+            app.logger.exception("TTS failed")
+            return jsonify({"error": str(e)}), 502
+
         tmp_mp3 = result[0]
         if not os.path.exists(tmp_mp3):
             return jsonify({"error": "TTS failed"}), 500
         shutil.copy(tmp_mp3, out_path)
         return jsonify({"url": f"/static/{out_name}", "chunks": 1})
 
-    # multi-part: fetch each piece, then concatenate with pydub
-    combined = None
-    for i, chunk in enumerate(parts, 1):
-        result = client.predict(chunk, voice, rate, pitch, api_name="/tts_interface")
-        tmp_mp3 = result[0]
-        if not os.path.exists(tmp_mp3):
-            return jsonify({"error": f"TTS failed on chunk {i}"}), 500
-        seg = AudioSegment.from_file(tmp_mp3, format="mp3")
-        combined = seg if combined is None else (combined + seg)
+    # multi-chunk path (note the indentation under `else:`)
+    else:
+        combined = None
+        for i, chunk in enumerate(parts, 1):
+            try:
+                result = call_tts(client, chunk, voice, rate, pitch)
+            except Exception as e:
+                app.logger.exception("TTS failed")
+                return jsonify({"error": str(e)}), 502
+
+            tmp_mp3 = result[0]
+            seg = AudioSegment.from_file(tmp_mp3, format="mp3")
+            combined = seg if combined is None else (combined + seg)
+
+            time.sleep(0.4)  # small pause between chunk requests
+
+        combined.export(out_path, format="mp3")
+        return jsonify({"url": f"/static/{out_name}", "chunks": len(parts)})
 
-    combined.export(out_path, format="mp3")
-    return jsonify({"url": f"/static/{out_name}", "chunks": len(parts)})
 
 # ======= New from index-cleaning app =======
 def extract_text_from_pdf(path):