Local server and large file upload #4528

The problem is in how you pass the file, not the 300 MB size itself — with a local Bot API server, sending files of up to 2000 MB is supported, so 300 MB is within the limit.

In your code you pass document=open('./test.zip', 'rb'). That tells PTB to upload the file: the whole archive is streamed in the HTTP request to your local server, and once it reaches a few hundred MB that request outlives the default timeouts, which is why you get telegram.error.TimedOut. It also explains why a ~100 MB file can still arrive even though the client already reported a timeout — a timeout only means the client stopped waiting for the request/response to finish, not that the server discarded the file.

With local_mode(True) there is a better way: pass the file path instead of a file object. When the document parameter is a str or a pathlib.Path, PTB checks whether the bot runs in local mode, and if it does, the file does not need to be uploaded at all — the local server reads it from disk itself:

from pathlib import Path

await context.bot.send_document(
    chat_id=ADMIN_ID,
    document=Path('/absolute/path/to/test.zip'),
)

Two conditions for this to work: use an absolute path, and make sure that path is readable by the telegram-bot-api process (same machine/filesystem, with permissions for the user/group you start it with via --username/--groupname), because it is the server — not your bot process — that opens the file. ./test.zip relative to the bot's working directory is not necessarily where the server will look. If you ever do have to upload a file object instead, raise the request's write/read timeouts, expect it to be much slower, and don't blindly retry after a TimedOut without checking whether the file was delivered, or you can create duplicates.