cancelreq

A blocking HTTP/1.1 client whose in-flight requests can be cancelled. Plain HTTP only, no TLS.

Quickstart

import threading

from cancelreq import get

cancel = threading.Event()
body = get(cancel, "http://example.com/")

Set the event from any thread to abort a request that is already running:

import threading

from cancelreq import RequestCancelled, get

cancel = threading.Event()
threading.Timer(0.5, cancel.set).start()

try:
    body = get(cancel, "http://example.com/slow")
except RequestCancelled:
    print("gave up")

POST a body, with headers and a timeout:

from cancelreq import post

body = post(
    cancel,
    "http://example.com/api",
    body='{"answer": 42}',
    headers={"Content-Type": "application/json"},
    timeout=5.0,
)

API

request(cancel, method, url, *, body=None, headers=None, timeout=None) -> bytes
get(cancel, url, *, headers=None, timeout=None) -> bytes
post(cancel, url, *, body=None, headers=None, timeout=None) -> bytes

get and post are shortcuts for request with that method.

Returns the response body. Raises RequestCancelled, HTTPStatusError (4xx/5xx, carrying .status, .reason and .body), TimeoutError, ConnectionError, or ProtocolError.

timeout defaults to None, meaning the request ends only when the server or cancel ends it.

Cancellation

Best effort, and honoured within ~50ms while connecting, while writing the request, and while waiting for the response. A host lookup already in flight runs to completion first.

Development

make test    # pytest
make check   # ty and ruff