Debian package builds were failing for two reasons:

 1. Python versions prior to 3.7 throw exceptions when attempting to print
    Unicode characters under a "C" locale. (#9076)

 2. We depended on `dh-systemd` which no longer exists in Debian Bullseye, but
    is necessary in Ubuntu Xenial. (#9073)

Setting `LANG="C.UTF-8"` in the build environment fixes the first issue.
See also: https://bugs.python.org/issue19846



The second issue is a bit trickier. The dh-systemd package was merged into
debhelper version 9.20160709 and a transitional package left in its wake.

The transitional dh-systemd package was removed in Debian Bullseye.

However, Ubuntu Xenial ships an older debhelper, and still needs dh-systemd.

Thus, builds were failing on Bullseye since we depended on a package which had
ceased existing, but we couldn't remove it from the debian/control file and our
build scripts because we still needed it for Ubuntu Xenial.

We can fix the debian/control issue by listing dh-systemd as an alternative to
the newer versions of debhelper. Since dh-systemd declares that it depends on
debhelper, Ubuntu Xenial will select its older dh-systemd which will in turn
pull in its older debhelper, resulting in no change from the status quo. All
other supported releases will satisfy the debhelper dependency constraint and
skip the dh-systemd alternative.

Build scripts were fixed by unconditionally attempting to install dh-systemd on
all releases and suppressing failures.

Once we drop support for Ubuntu Xenial, we can revert most of this commit and
rely on the version constraint on debhelper in debian/control.

Fixes #9076
Fixes #9073

Signed-off-by: Dan Callahan <danc@element.io>

This removes the version pin of the `prometheus_client` dependency, in direct response to #8831. If merged, this will close #8831 

As far as I can tell, no other changes are needed, but as I'm no synapse expert, I'm relying heavily on CI and maintainer reviews for this. My very primitive test of synapse with prometheus_client v0.9.0 on my home server didn't bring up any issues, so we'll see what happens.

Signed-off-by: Jordan Bancino

Short-term fix for https://github.com/matrix-org/synapse/issues/8766.

This bumps us closer to current Python without going all the way to 3.9.

Fixes #8674

Signed-off-by: Dan Callahan <danc@element.io>

Signed-off-by: Mateusz Przybyłowicz <uamfhq@gmail.com>

Signed-off-by: Christopher May-Townsend <chris@maytownsend.co.uk>

We do this to prevent foot guns. The default config uses a MemoryFilter,
but users are free to change to logging to files directly. If they do
then they have to ensure to set the `filters: [context]` on the right
handler, otherwise records get written with the wrong context.

Instead we move the logic to happen when we generate a record, which is
when we *log* rather than *handle*.

(It's possible to add filters to loggers in the config, however they
don't apply to descendant loggers and so they have to be manually set on
*every* logger used in the code base)

As mentioned in #7397, switching to a debian base should help with multi-arch work to save time on compiling. This is unashamedly based on #6373, but without the extra functionality. Switch python version back to generic 3.7 to always pull the latest. Essentially, keeping this as small as possible. The image is bigger though unfortunately.

* Add libwebp dependency to Dockerfile

Signed-off-by: Juho Vanhanen <juho@vanhanen.io>

Upstream have merged our changes
(https://github.com/spotify/dh-virtualenv/pull/300), so let's switch back to it
instead of using our fork.

When we tried to build debs for 1.13.0, the build failed because docker used a
base docker image which had a stale apt cache.

Fixes: #7540

Lots of people seem to get confused by this mode, and it's been deprecated
since Synapse 1.1.0. It's time for it to go.

* Add working build command for docker image

* Add changelog

Signed-off-by: Tobia De Koninck <LEDfan@users.noreply.github.com>

Turns out that loggers that are instantiated before the config is loaded get
turned off.

Also bring the logging config that is generated by --generate-config into line.

Fixes #6194.

* Allow passing SYNAPSE_WORKER envvar

* changelog.d

* Document SYNAPSE_WORKER.

Attempting to imply that you don't need to change this default
unless you're in worker mode.

Also aware that there's a bigger problem of attempting to document
a complete working configuration of workers using docker, as we
currently only document to use `synctl` for worker mode, and synctl
doesn't work that way in docker.

Adjust su-exec to only be used if needed.

If UID == getuid() and GID == getgid() then we do not need to su-exec, and chmod will not work.

* Fix debian packages for sid being called buster.

I don't know why the sid images return buster as its codename in
`lsb_release` but it does, so lets just grab the codename from the
distro we pass into dockerfile

* Newsfile

This is basically a contrived way of adding a `Recommends` on `libpq5`, to fix #5653.

The way this is supposed to happen in debhelper is to run
`dh_shlibdeps`, which in turn runs `dpkg-shlibdeps`, which spits things out
into `debian/<package>.substvars` whence they can later be included by
`control`.

Previously, we had disabled `dh_shlibdeps`, mostly because `dpkg-shlibdeps`
gets confused about PIL's interdependent objects, but that's not really the
right thing to do and there is another way to work around that.

Since we don't always use postgres, we don't necessarily want a hard Depends on
libpq5, so I've actually ended up adding an explicit invocation of
`dpkg-shlibdeps` for `psycopg2`.

I've also updated the build-depends list for the package, which was missing a
couple of entries.

This adds a missing space, without which log lines appear uglier.

Signed-off-by: Slavi Pantaleev <slavi@devture.com>

Alpine Linux 3.8 is still supported, but it seems like
it's quite outdated now.

While Python should be the same on both, all other libraries, etc.,
are much newer in Alpine 3.9 and 3.10.

Signed-off-by: Slavi Pantaleev <slavi@devture.com>

Removes any `SMTP_*` docker container environment variables from having any effect on the default config.

Fixes https://github.com/matrix-org/synapse/issues/5430

Signed-off-by: Amir Zarrinkafsh <nightah@me.com>

... to help people escape env var hell

There's not much point in binding to localhost when it's in a docker container.

This is mostly a documentation change, but also adds a default value for
SYNAPSE_CONFIG_PATH, so that running from the generated config is the default,
and will Just Work provided your config is in the right place.

When running under docker, we want to use docker's own logging stuff rather
than losing the logs somewhere on the container's filesystem, so let's use log
configs that spit logs out to stdout instead.

Fixes #4830.