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urllib3 Production Incidents & Fixes

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Configuration error

issues: 166 fresh: 18 indexable

Data consistency

issues: 22 fresh: 3 indexable

SSL handshake

issues: 16 fresh: 3 indexable

Top Queries / Error Strings

These are the lines developers tend to paste into Google during incidents.

... (truncated) ...

Is it something you currently cannot do?

_HTTPConnection.__init__(self, *args, **kw)

self._validate_conn(conn)

"/_alias/%s"%self.index_name)

$ python3 -m ensurepip --upgrade --default-pip

$ source venv/bin/activate

'2.7.6 (default, Nov 13 2018, 12:45:42) \n[GCC 4.8.4]'

'subjectAltName': get_subj_alt_name(x509)

'urllib3.contrib.pyopenssl' module is deprecated and will be removed in a future release of urllib3 2.x.

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Connection retrieved from connection pool has wrong cert_reqs (based on previous request)

#500 · urllib3/urllib3

urllib3 keeps connection open after failed fingerprint validation

#529 · urllib3/urllib3

ca_cert_dir keyword argument may be passed to HTTPConnectionPool by accident.

#750 · urllib3/urllib3

Multipart mixed responses generate warnings

#800 · urllib3/urllib3

PyOpenSSL: Fails to import after installation with the provided instructions

#839 · urllib3/urllib3

Unexpected HostChangedError due to downcasing of hostname

#1032 · urllib3/urllib3

Bug: Content-Disposition Header Lacking "filename" When "filename*" Is Present

#1062 · urllib3/urllib3

Custom LifoQueue

#1087 · urllib3/urllib3

urllib3==1.21: TypeError: unhashable type: 'list'

#1165 · urllib3/urllib3

IndexError when handle malformed http response

#1286 · urllib3/urllib3

Interrupted system call while profiling with plop

#1396 · urllib3/urllib3

Accessing HTTPS sites through proxy

#1520 · urllib3/urllib3

Stop using unittest's addCleanup

#1623 · urllib3/urllib3

Can't connect to IPv6 Address with Zone ID

#1641 · urllib3/urllib3

Add `other` counter to Retry for fully fine-grained retry configuration

#1746 · urllib3/urllib3

test_https_timeout & test_enhanced_timeout fail when there's no networking

#1756 · urllib3/urllib3

UnicodeError while processing invalid redirect

#1769 · urllib3/urllib3

Issue with Parsing URIs - Breaks Security Tools when testing for Path Traversal

#1790 · urllib3/urllib3

urllib3 hanging inside call to PoolManager request

#1808 · urllib3/urllib3

test_delayed_body_read_timeout_with_preload is flaky

#1883 · urllib3/urllib3

parse_retry_after() in utils/retry.py computes seconds incorrectly when Retry-After value is a http-date and local time

#1896 · urllib3/urllib3

Incorrect handling of Retry-After (2.7)

#1934 · urllib3/urllib3

SecureTransport does not close unverified connections correctly

#1976 · urllib3/urllib3

keylog_filename triggering error when SSLKEYLOGFILE is not set

#2015 · urllib3/urllib3

v.1.26+ doesn't support SSL in python 2.7.6

#2051 · urllib3/urllib3

v1.26.3 breaks SSL support in Python 2.7.6

#2165 · urllib3/urllib3

HTTPSConnection fails when assert_hostname is True

#2126 · urllib3/urllib3

Fix `OSError: [Errno 98] Address already in use` in `bind_sockets` call in CI

#2171 · urllib3/urllib3

Cert verify on subjectAltName->"IP Address" not working when doing IPv6 via a proxy

#2240 · urllib3/urllib3

Allow using HTTPHeaderDict and multiple header keys in requests

#2242 · urllib3/urllib3

Deprecate urllib3.request module

#2269 · urllib3/urllib3

Hostname matching doesn't strip trailing '.' when connecting with proxy

#2244 · urllib3/urllib3

[v2] Chaining exceptions

#2313 · urllib3/urllib3

Incorrect "Your proxy appears to only use HTTP and not HTTPS" error message during connection errors to HTTPS websites

#2564 · urllib3/urllib3

OverflowError: signed integer is greater than maximum

#2513 · urllib3/urllib3

IPv6 zone ID shouldn't be used during certificate hostname matching

#2637 · urllib3/urllib3

`python_requires` prevents install of recent urllib3 when using Poetry

#2761 · urllib3/urllib3

urllib3 2 causes partial response to be returned (using requests 2.30.0)

#3009 · urllib3/urllib3

v2.x : Breaks `assert_hostname = False`

#3051 · urllib3/urllib3

test_socketlevel has some flaky tests

#3164 · urllib3/urllib3

request(..., preload_content=False).read(-1) raises an unexpected Exception

#3122 · urllib3/urllib3

Incorrect behaviour of `proxy_is_verified`

#3130 · urllib3/urllib3

Handle OpenSSL 3.2.0 new error message for unexpected unencrypted records

#3268 · urllib3/urllib3

pypy tests often fail in CI with reason "cancelled after 30 minutes"

#3305 · urllib3/urllib3

urllib3 2.2 explicitly casts all headers to HTTPHeaderDict

#3343 · urllib3/urllib3

imprecise types on `urllib3.Retry.new` / `urllib3.Retry.increment`

#3363 · urllib3/urllib3

ReadTimeoutError doesn't pickle / maintain the str parsing

#3567 · urllib3/urllib3

Resolve environment variables (and home directory?) within SSLKEYLOGFILE path

#3700 · urllib3/urllib3

Redirects do not work on a PoolManager configured with custom retries

#3649 · urllib3/urllib3