Error Handling¶

Errors can be correctly handled with try...except blocks in order to control the behaviour of your application. wzgram errors all live inside the errors package:

from pyrogram import errors

RPCError¶

The father of all errors is named RPCError and is able to catch all Telegram API related errors. This error is raised every time a method call against Telegram’s API was unsuccessful.

from pyrogram.errors import RPCError

Warning

Avoid catching this error everywhere, especially when no feedback is given (i.e. by logging/printing the full error traceback), because it makes it impossible to understand what went wrong.

Error Categories¶

The RPCError packs together all the possible errors Telegram could raise, but to make things tidier, wzgram provides categories of errors, which are named after the common HTTP errors and are subclass-ed from the RPCError:

from pyrogram.errors import BadRequest, Forbidden, ...

303 - SeeOther
400 - BadRequest
401 - Unauthorized
403 - Forbidden
406 - NotAcceptable
420 - Flood
500 - InternalServerError

Single Errors¶

For a fine-grained control over every single error, wzgram does also expose errors that deal each with a specific issue. For example:

from pyrogram.errors import FloodWait

These errors subclass directly from the category of errors they belong to, which in turn subclass from the father RPCError, thus building a class of error hierarchy such as this:

RPCError
- BadRequest
  
  MessageEmpty
  
  UsernameOccupied
  
  ...
- InternalServerError
  
  RpcCallFail
  
  InterDcCallError
  
  ...
- ...

Unknown Errors¶

In case wzgram does not know anything about a specific error yet, it raises a generic error from its known category, for example, an unknown error with error code 400, will be raised as a BadRequest. This way you can catch the whole category of errors and be sure to also handle these unknown errors.

RPC Errors

There is no official list of every RPC error Telegram can return, so the list of known errors is maintained on a best-effort basis. When new methods appear, the list may lag behind simply because nobody knows yet what they can raise.

An unknown error is logged at warning level, with the error string and the raw function that caused it:

Unknown RPC error [420 SOME_NEW_ERROR] caused by messages.SendMessage

Earlier versions wrote these to an unknown_errors.txt file in the working directory. They no longer do: the write was unbounded, it blocked the event loop from inside an exception constructor, and on a read-only filesystem the resulting OSError replaced the RPC error being raised. Capture them from logging instead.

Errors with Values¶

Exception objects may also contain some informative values. For example, FloodWait holds the amount of seconds you have to wait before you can try again, some other errors contain the DC number on which the request must be repeated on. The value is stored in the value attribute of the exception object:

import asyncio
from pyrogram.errors import FloodWait

...
    try:
        ...  # Your code
    except FloodWait as e:
        await asyncio.sleep(e.value)  # Wait N seconds before continuing
...