Fix FastTelethon 500 errors: PeerChannel entity resolution and temp_path UnboundLocalError

Author: itskavin

python_service/main.py

@@ -14,6 +14,7 @@
 from fastapi.responses import StreamingResponse, HTMLResponse
 from telethon import TelegramClient, utils
 from telethon.tl import types
+from telethon.tl.types import PeerChannel
 from telethon.errors import SessionPasswordNeededError, PhoneCodeInvalidError
 import uvicorn
 
@@ -426,6 +427,8 @@ async def upload_large_file(
     if not target_channel:
         raise HTTPException(status_code=400, detail="Channel ID required")
 
+    temp_path = None  # Initialize to avoid UnboundLocalError
+    
     try:
         # Save uploaded file temporarily
         temp_path = f"/tmp/{file.filename}"
@@ -481,7 +484,7 @@ async def progress_callback(current, total):
 
     except Exception as e:
         logger.error(f"Upload failed: {e}", exc_info=True)
-        if os.path.exists(temp_path):
+        if temp_path and os.path.exists(temp_path):
             os.remove(temp_path)
         raise HTTPException(status_code=500, detail=f"Upload failed: {str(e)}")
 
@@ -498,11 +501,18 @@ async def download_large_file(channel_id: str, message_id: int):
     if not client or not await client.is_user_authorized():
         raise HTTPException(status_code=503, detail="Telegram client not ready")
 
+    temp_path = None  # Initialize to avoid UnboundLocalError
+    
     try:
         logger.info(f"Fetching message {message_id} from channel {channel_id}...")
 
+        # Convert channel_id string to integer and create PeerChannel
+        # This helps Telethon resolve the entity correctly
+        channel_id_int = int(channel_id)
+        peer = PeerChannel(utils.resolve_id(channel_id_int)[0])
+        
         # Get the message
-        message = await client.get_messages(channel_id, ids=message_id)
+        message = await client.get_messages(peer, ids=message_id)
 
         if not message or not message.document:
             raise HTTPException(status_code=404, detail="File not found")
@@ -554,7 +564,7 @@ def file_iterator():
         raise
     except Exception as e:
         logger.error(f"Download failed: {e}", exc_info=True)
-        if os.path.exists(temp_path):
+        if temp_path and os.path.exists(temp_path):
             os.remove(temp_path)
         raise HTTPException(status_code=500, detail=f"Download failed: {str(e)}")
 
@@ -566,7 +576,11 @@ async def get_file_info(channel_id: str, message_id: int):
         raise HTTPException(status_code=503, detail="Telegram client not ready")
 
     try:
-        message = await client.get_messages(channel_id, ids=message_id)
+        # Convert channel_id string to integer and create PeerChannel
+        channel_id_int = int(channel_id)
+        peer = PeerChannel(utils.resolve_id(channel_id_int)[0])
+        
+        message = await client.get_messages(peer, ids=message_id)
 
         if not message or not message.document:
             raise HTTPException(status_code=404, detail="File not found")

render.yaml

@@ -11,11 +11,12 @@ services:
     plan: free  # Change to 'standard' or higher for production
     region: singapore  # Choose your region
     branch: main
+    autoDeploy: false  # Disable auto-deploy (manual deploy only)
     envVars:
       - key: RUST_LOG
         value: info
       - key: FASTTELETHON_URL
-        value: changeme_to_your-other_render_service_url
+        value: https://fasttelethon.onrender.com  # Update with your FastTelethon service URL
       - key: BOT_TOKEN
         sync: false  # Set manually in Render dashboard
       - key: STORAGE_CHANNEL_ID