0.20.0 (13th October, 2021)

The 0.20.0 release adds an integrated command-line client, and also includes some design changes. The most notable of these is that redirect responses are no longer automatically followed, unless specifically requested.

This design decision prioritises a more explicit approach to redirects, in order to avoid code that unintentionally issues multiple requests as a result of misconfigured URLs.

For example, previously a client configured to send requests to http://api.github.com/ would end up sending every API request twice, as each request would be redirected to https://api.github.com/.

If you do want auto-redirect behaviour, you can enable this either by configuring the client instance with Client(follow_redirects=True), or on a per-request basis, with .get(..., follow_redirects=True).

This change is a classic trade-off between convenience and precision, with no "right" answer. See discussion #1785 for more context.

The other major design change is an update to the Transport API, which is the low-level interface against which requests are sent. Previously this interface used only primitive datastructures, like so...

(status_code, headers, stream, extensions) = transport.handle_request(method, url, headers, stream, extensions)
try
    ...
finally:
    stream.close()

Now the interface is much simpler...

response = transport.handle_request(request)
try
    ...
finally:
    response.close()

Changed

• The allow_redirects flag is now follow_redirects and defaults to False.
• The raise_for_status() method will now raise an exception for any responses except those with 2xx status codes. Previously only 4xx and 5xx status codes would result in an exception.
• The low-level transport API changes to the much simpler response = transport.handle_request(request).
• The client.send() method no longer accepts a timeout=... argument, but the client.build_request() does. This required by the signature change of the Transport API. The request timeout configuration is now stored on the request instance, as request.extensions['timeout'].

Added

• Added the httpx command-line client.
• Response instances now include .is_informational, .is_success, .is_redirect, .is_client_error, and .is_server_error properties for checking 1xx, 2xx, 3xx, 4xx, and 5xx response types. Note that the behaviour of .is_redirect is slightly different in that it now returns True for all 3xx responses, in order to allow for a consistent set of properties onto the different HTTP status code types. The response.has_redirect_location location may be used to determine responses with properly formed URL redirects.

Fixed

• response.iter_bytes() no longer raises a ValueError when called on a response with no content. (Pull #1827)
• The 'wsgi.error' configuration now defaults to sys.stderr, and is corrected to be a TextIO interface, not a BytesIO interface. Additionally, the WSGITransport now accepts a wsgi_error confguration. (Pull #1828)
• Follow the WSGI spec by properly closing the iterable returned by the application. (Pull #1830)