Logging

If you need to inspect the internal behaviour of httpcore, you can use Python's standard logging to output debug level information.

For example, the following configuration...

import logging
import httpcore

logging.basicConfig(
    format="%(levelname)s [%(asctime)s] %(name)s - %(message)s",
    datefmt="%Y-%m-%d %H:%M:%S",
    level=logging.DEBUG
)

httpcore.request('GET', 'https://www.example.com')

Will send debug level output to the console, or wherever stdout is directed too...

DEBUG [2023-01-09 14:44:00] httpcore.connection - connect_tcp.started host='www.example.com' port=443 local_address=None timeout=None
DEBUG [2023-01-09 14:44:00] httpcore.connection - connect_tcp.complete return_value=<httpcore.backends.sync.SyncStream object at 0x109ba6610>
DEBUG [2023-01-09 14:44:00] httpcore.connection - start_tls.started ssl_context=<ssl.SSLContext object at 0x109e427b0> server_hostname='www.example.com' timeout=None
DEBUG [2023-01-09 14:44:00] httpcore.connection - start_tls.complete return_value=<httpcore.backends.sync.SyncStream object at 0x109e8b050>
DEBUG [2023-01-09 14:44:00] httpcore.http11 - send_request_headers.started request=<Request [b'GET']>
DEBUG [2023-01-09 14:44:00] httpcore.http11 - send_request_headers.complete
DEBUG [2023-01-09 14:44:00] httpcore.http11 - send_request_body.started request=<Request [b'GET']>
DEBUG [2023-01-09 14:44:00] httpcore.http11 - send_request_body.complete
DEBUG [2023-01-09 14:44:00] httpcore.http11 - receive_response_headers.started request=<Request [b'GET']>
DEBUG [2023-01-09 14:44:00] httpcore.http11 - receive_response_headers.complete return_value=(b'HTTP/1.1', 200, b'OK', [(b'Age', b'572646'), (b'Cache-Control', b'max-age=604800'), (b'Content-Type', b'text/html; charset=UTF-8'), (b'Date', b'Mon, 09 Jan 2023 14:44:00 GMT'), (b'Etag', b'"3147526947+ident"'), (b'Expires', b'Mon, 16 Jan 2023 14:44:00 GMT'), (b'Last-Modified', b'Thu, 17 Oct 2019 07:18:26 GMT'), (b'Server', b'ECS (nyb/1D18)'), (b'Vary', b'Accept-Encoding'), (b'X-Cache', b'HIT'), (b'Content-Length', b'1256')])
DEBUG [2023-01-09 14:44:00] httpcore.http11 - receive_response_body.started request=<Request [b'GET']>
DEBUG [2023-01-09 14:44:00] httpcore.http11 - receive_response_body.complete
DEBUG [2023-01-09 14:44:00] httpcore.http11 - response_closed.started
DEBUG [2023-01-09 14:44:00] httpcore.http11 - response_closed.complete
DEBUG [2023-01-09 14:44:00] httpcore.connection - close.started
DEBUG [2023-01-09 14:44:00] httpcore.connection - close.complete

The exact formatting of the debug logging may be subject to change across different versions of httpcore. If you need to rely on a particular format it is recommended that you pin installation of the package to a fixed version.