The default value in uwsgi is 4k; receiving more than this amount from
nginx leads to a 502 response (though, happily, the backend uwsgi does not
terminate).
ab18dbfde5 originally increased it from the unstated uwsgi default
of 4096, to 8192; b1da797955 made it configurable, in order to allow
requests from clients with many cookies, without causing 502's[1].
nginx defaults to a limitation of 1k, with 4 additional 8k header
lines allowed[2]; any request larger than that returns a response of
`400 Request Header Or Cookie Too Large`. The largest header size
theoretically possible from nginx, by default, is thus 33k, though
that would require packing four separate headers to exactly 8k each.
Remove the gap between nginx's limit and uwsgi's, which could trigger
502s, by removing the uwsgi configurability, and setting a 64k size in
uwsgi (the max allowable), which is larger than nginx's default limit.
uWSGI's documentation of `buffer-size` ([3], [4]) also notes that "It
is a security measure too, so adapt to your app needs instead of
maxing it out." Python has no security issues with buffers of 64k,
and there is no appreciable memory footprint difference to having a
larger buffer available in uwsgi.
[1]: https://chat.zulip.org/#narrow/stream/31-production-help/topic/works.20in.20Edge.20not.20Chrome/near/719523
[2]: https://nginx.org/en/docs/http/ngx_http_core_module.html#client_header_buffer_size
[3]: https://uwsgi-docs.readthedocs.io/en/latest/ThingsToKnow.html
[4]: https://uwsgi-docs.readthedocs.io/en/latest/Options.html#buffer-size
Backups are written every 16k of WAL archive, and by default do not
have an upper limit on how out of date they are, as `archive_timeout`
defaults to 0.
Also emphasize that these are streaming backups, not just one
point-in-time backup daily.
Fixes#21976.
Notable changes:
- Describe `X-Forwarded-For` by name.
- Switch each specific proxy to numbered steps.
- Link back to the `X-Forwarded-For` section in each proxy
- Default to using HTTPS, not HTTP, for the backend.
- Include the HTTP-to-HTTPS redirect code for all proxies; it is
important that it happen at the proxy, as the backend is unaware of
it.
- Call out Apache2 modules which are necessary.
- Specify where the dhparam.pem file can be found.
- Call out the `Host:` header forwarding necessary, and document
`USE_X_FORWARDED_HOST` if that is not possible.
- Standardize on 20 minutes of connection timeout.
As a consequence:
• Bump minimum supported Python version to 3.8.
• Move Vagrant environment to Ubuntu 20.04, which has Python 3.8.
• Move CI frontend tests to Ubuntu 20.04.
• Move production build test to Ubuntu 20.04.
• Move 3.4 upgrade test to Ubuntu 20.04.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
On the Debian 10 -> 11 upgrade, the server is running Zulip 4.x, which
lets us pass `--audit-fts-indexes` to `upgrade-zulip-stage-2` rather
than run the command as a separate step.
The reindex-textual-data tool needs the venv to be cable to run;
switch the order of the last two steps, making them now match the
Debian 9 -> 10 and 10 -> upgrades.
Ref #21296.
When the credentials are provided by dint of being run on an EC2
instance with an assigned Role, we must be able to fetch the instance
metadata from IMDS -- which is precisely the type of internal-IP
request that Smokescreen denies.
While botocore supports a `proxies` argument to the `Config` object,
this is not actually respected when making the IMDS queries; only the
environment variables are read from. See
https://github.com/boto/botocore/issues/2644
As such, implement S3_SKIP_PROXY by monkey-patching the
`botocore.utils.should_bypass_proxies` function, to allow requests to
IMDS to be made without Smokescreen impeding them.
Fixes#20715.
Previously, it was possible to configure `wal-g` backups without
replication enabled; this resulted in only daily backups, not
streaming backups. It was also possible to enable replication without
configuring the `wal-g` backups bucket; this simply failed to work.
Make `wal-g` backups always streaming, and warn loudly if replication
is enabled but `wal-g` is not configured.
Ubuntu 22.04 pushed a post-feature-freeze update to Python 3.10,
breaking virtual environments in a Debian patch
(https://bugs.launchpad.net/ubuntu/+source/python3.10/+bug/1962791).
Also, our antique version of Tornado doesn’t work in 3.10, and we’ll
need to do some work to upgrade that.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
This uses the myst_heading_anchors option to automatically generate
header anchors and make Sphinx aware of them. See
https://myst-parser.readthedocs.io/en/latest/syntax/optional.html#auto-generated-header-anchors.
Note: to be compatible with GitHub, MyST-Parser uses a slightly
different convention for .md fragment links than .html fragment links
when punctuation is involved. This does not affect the generated
fragment links in the HTML output.
Fixes#13264.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
We previously had a convention of redundantly including the directory
in relative links to reduce mistakes when moving content from one file
to another. However, these days we have a broken link checker in
test-documentation, and after #21237, MyST-Parser will check relative
links (including fragments) when you run build-docs.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
This was only used for upgrading from Zulip < 1.9.0, which is no
longer possible because Zulip < 2.1.0 had no common supported
platforms with current main.
If we ever want this optimization for a future migration, it would be
better implemented using Django merge migrations.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
Alex Vandiver
Anders Kaseorg
Mateusz Mandera
Lorenzo Milesi
rht
Alya Abbott