Relying on `defined(Class['...'])` makes the class sensitive to
resource evaluation ordering, and thus brittle. It is also only
functional for a single service (thumbor).
Generalize by using `purge => true` for the directory to automatically
remove all un-managed files. This is more general than the previous
form, and may result in additional not-managed services being removed.
Restarting servers is what can cause service interruptions, and
increase risk. Add all of the servers that we use to the list of
ignored packages, and uncomment the default allowed-origins in order
to enable unattended upgrades.
d2aa81858c replaced the `apt::source` to set up debathena with
`Exec['setup-apt-repo-debathena']`, but mistakenly left the
`apt::source` in place in `zmirror` (but not `zmirror_personals`).
The `apt::source` resource type was later removed in c9d54f7854,
making the manifest to apply on `zmirror`.
Remove the broken and unnecessary `apt::source` resource.
This property is not related to the base zulip install; move it to
zulip::postgres_common, which is already used as a namespace for
various postgres variables.
There was likely more dependency complexity prior to 97766102df, but
there is now no reason to require that consumers explicitly include
zulip::apt_repository.
Use https://github.com/stripe/smokescreen to provide a server for an
outgoing proxy, run under supervisor. This will allow centralized
blocking of internal metadata IPs, localhost, and so forth, as well as
providing default request timeouts (10s by default).
We should eventually add templating for the set of hosts here, but
it's worth merging this change to remove the deleted hostname and
replace it with the current one.
Disabled on webservers in 047817b6b0, it has since lingered in
configuration, as well as running (to no effect) every minute on the
loadbalancer.
Remove the vestiges of its configuration.
This banner shows on lb1, advertising itself as lb0. There is no
compelling reason for a custom motd, especially one which needs to
be reconfigured for each host.
Since this was using repead individual get() calls previously, it
could not be monitored for having a consumer. Add it in, by marking
it of queue type "consumer" (the default), and adding Nagios lines for
it.
Also adjust missedmessage_emails to be monitored; it stopped using
LoopQueueProcessingWorker in 5cec566cb9, but was never added back
into the set of monitored consumers.
The rabbitmq cron jobs exist in order to call rabbitmqctl as root and
write the output to files that nagios can consume, since nagios is not
allowed to run rabbitmqctl.
In systems which do not have nagios configured, these every-minute
cron jobs add non-insignificant load, to no effect. Move their
installation into `zulip_ops`. In doing so, also combine the cron.d
files into a single file; this allows us to `ensure => absent` the old
filenames, removing them from existing systems. Leave the resulting
combined cron.d file in `zulip`, since it is still of general utility
and note.
The configuration change made in 1c17583ad5 only allowed delivery to
those specific Zulip addresses. However, they also prevent the
mailserver from being used as an outgoing email relay from Zulip,
since all mail that passed through the mailserver (from any
originator) was required to have a `RCPT TO` that matched those
regexes.
Allow mail originating from `mynetworks` to have an arbitrary
addresses in `RCPT TO`.
Use the validation of the tornado sharding config that
`stage_updated_sharding` does, by depending on it. This ensures that
we don't write out a supervisor or nginx config based on a
bad (e.g. non-sequential) list of tornado ports.
Fingerprinting the config is somewhat brittle -- it requires either
custom bootstrapping for old (fingerprint-less) configs, and may have
false-positives.
Since generating the config is lightweight, do so into the .tmp files,
and compare the output to the originals to determine if there are
changes to apply.
In order to both surface errors, as well as notify the user in case a
restart is necessary, we must run it twice. The `onlyif`
functionality cannot show configuration errors to the user, only
determine if the command runs or not. We thus run the command once,
judging errors as "interesting" enough to run the actual command,
whose failure will be verbose in Puppet and halt any steps that depend
on it.
Removing the `onlyif` would result in `stage_updated_sharding` showing
up in the output of every Puppet run, which obscures the important
messages it displays when an update to sharding is necessary.
Removing the `command` (e.g. making it an `echo`) would result in
removing the ability to report configuration errors. We thus have no
choice but to run it twice; this is thankfully low-overhead.
We can compute the intended number of processes from the sharding
configuration. In doing so, also validate that all of the ports are
contiguous.
This removes a discrepancy between `scripts/lib/sharding.py` and other
parts of the codebase about if merely having a `[tornado_sharding]`
section is sufficient to enable sharding. Having behaviour which
changes merely based on if an empty section exists is surprising.
This does require that a (presumably empty) `9800` configuration line
exist, but making that default explicit is useful.
After this commit, configuring sharding can be done by adding to
`zulip.conf`:
```
[tornado_sharding]
9800 = # default
9801 = other_realm
```
Followed by running `./scripts/refresh-sharding-and-restart`.
In development and test, we keep the Tornado port at 9993 and 9983,
respectively; this allows tests to run while a dev instance is
running.
In production, moving to port 9800 consistently removes an odd edge
case, when just one worker is on an entirely different port than if
two workers are used.
Without an explicit port number, the `stdout_logfile` values for each
port are identical. Supervisor apparently decides that it will
de-conflict this by appending an arbitrary number to the end:
```
/var/log/zulip/tornado.log
/var/log/zulip/tornado.log.1
/var/log/zulip/tornado.log.10
/var/log/zulip/tornado.log.2
/var/log/zulip/tornado.log.3
/var/log/zulip/tornado.log.7
/var/log/zulip/tornado.log.8
/var/log/zulip/tornado.log.9
```
This is quite confusing, since most other files in `/var/log/zulip/`
use `.1` to mean logrotate was used. Also note that these are not all
sequential -- 4, 5, and 6 are mysteriously missing, though they were
used in previous restarts. This can make it extremely hard to debug
logs from a particular Tornado shard.
Give the logfiles a consistent name, and set them up to logrotate.
Making this include "zulip-tornado" makes it clearer in supervisor
logs. Without this, one only sees:
```
2020-09-14 03:43:13,788 INFO waiting for port-9807 to stop
2020-09-14 03:43:14,466 INFO stopped: port-9807 (exit status 1)
2020-09-14 03:43:14,469 INFO spawned: 'port-9807' with pid 24289
2020-09-14 03:43:15,470 INFO success: port-9807 entered RUNNING state, process has stayed up for > than 1 seconds (startsecs)
```
This supports running puppet to pick up new sharding changes, which
will warn of the need to finalize them via
`refresh-sharding-and-restart`, or simply running that directly.
Clients that close their socket to nginx suddenly also cause nginx to close
its connection to uwsgi. When uwsgi finishes computing the response,
it thus tries to write to a closed socket, and generates either
IOError or SIGPIPE failures.
Since these are caused by the _client_ closing the connection
suddenly, they are not actionable by the server. At particularly high
volumes, this could represent some sort of server-side failure;
however, this is better detected by examining status codes at the
loadbalancer. nginx uses the error code 499 for this occurrence:
https://httpstatuses.com/499
Stop uwsgi from generating this family of exception entirely, using
configuration for uwsgi[1]; it documents these errors as "(annoying),"
hinting at their general utility."
[1] https://uwsgi-docs.readthedocs.io/en/latest/Options.html#ignore-sigpipe
Increasing the uwsgi listen backlog is intended to allow it to handle
higher connection rates during server restart, when many clients may
be trying to connect. The kernel, in turn, needs to have a
proportionally increased somaxconn soas to not refuse the connection.
Set somaxconn to 2x the uwsgi backlog, but no lower than the
default (128).
Prior to PostgreSQL 12, the `recovery_target_timeline` setting is only
valid in a `recovery.conf` file, as that file has its own
configuration parser. As such, including it in `postgresql.conf`
results in an error, and PostgreSQL will fail to start.
Remove the setting, reverting bff3b540b1. This fixes PostgreSQL 9.5,
9.6, 10, and 11; while the setting is not an error in a PostgreSQL 12
configuration file, it is unnecessary since `latest` is the default.
7d4a370a57 attempted to move the replication check to on the
PostgreSQL hosts. While it updated the _check_ to assume it was
running and talking to a local PostgreSQL instance, the configuration
and installation for the check were not updated. As such, the check
ran on the nagios host for each DB host, and produced no output.
Start distributing the check to all apopdb hosts, and configure nagios
to use the SSH tunnel to get there.
wal-g was used in `puppet/zulip` by env-wal-g, but only installed in
`puppet/zulip_ops`.
Merge all of the dependencies of doing backups using wal-g (wal-g
installation, the pg_backup_and_purge job, the nagios plugin that
verifies it happens) into a common base class in `puppet/zulip`, since
it is generally useful.
No plugins are installed inside the /usr/local/munin/lib this creates
in munin-node, nor are they symlinked into /etc/munin/plugins, so
non-default plugins are added by this.
The one complexity is that hosts_fullstack are treated differently, as
they are not currently found in the manual `hosts` list, and as such
do not get munin monitoring.
check_memcached does not support memcached authentication even in its
latest release (it’s in a TODO item comment, and that’s it), and was
never particularly useful.
When supervisor is first installed, it is started automatically, and
creates the socket, owned by root. Subsequent reconfiguration in
puppet only calls `reread + update`, which is insufficient to apply
the `chown = zulip:zulip` line in `supervisord.conf`, leaving the
socket owned by `root` and the last part of the installation unable to
restart `supervisor` services as the `zulip` user. The `chown` line
in `scripts/lib/install` exists to paper over this.
Add a separate exec target for changes to `supervisord.conf` itself,
which restarts the full service. This leaves the default `restart`
action on the service for the lightweight `reread + update` action,
which is more common.
We use `systemctl` only on redhat-esque builds, because CI runs
Ubuntu, but init is not systemd in that context. `systemctl reload`
is sufficient to re-apply the socket ownership, but a full `restart`
and not `reload` is necessary under `/etc/init.d/supervisor`.
wal-g has a slihghtly different format than wal-e in its `backup-list`
output; it only contains three columns:
- `name`
- `last_modified`,
- `wal_segment_backup_start`
..rather than wal-e's plethora, most of which were blank:
- `name`
- `last_modified`
- `expanded_size_bytes`
- `wal_segment_backup_start`
- `wal_segment_offset_backup_start`
- `wal_segment_backup_stop`
- `wal_segment_offset_backup_stop`
Remove one argument from the split.
In Bionic, nagios-plugins-basic is a transitional package which
depends on monitoring-plugins-basic. In Focal, it is a virtual
package, which means that every time puppet runs, it tries to
re-install the nagios-plugins-basic package.
Switch all instances to referring to `$zulip::common::nagios_plugins`,
and repoint that to monitoring-plugins-basic.
Frontend hosts in multiple-host configurations (including docker
hosts) need a `psql` binary installed. ca9d27175b switched to not
setting `postgresql.version` in `zulip.conf`, which in turn means that
`$zulip::base::postgres_version` is unset. This, in turn, led to the
frontend hosts installing `postgresql-client-`, whose trailing dash
causes apt to _uninstall_ that package.
Unconditionally install `postgresql-client` with no explicit version
attached. This is a metapackage which depends on the latest client
package, which currently means it will install `postgresql-client-12`.
On single-host installs which have configured `postgresql.version` in
`zulip.conf` to be a lower version, this will result in
`postgresql-client-12` existing alongside another
version (e.g. `postgresql-client-10`); `psql` will give the most
recent. This is acceptable because the semantic meaning of the
postgresql version in `zulip.conf` is about the database engine
itself, not the command-line client.
Support for Xenial and Stretch was removed (5154ddafca, 0f4b1076ad,
8944e0ad53, 79acd5ae40, 1219a2e854), but not all codepaths were
updated to remove their conditionals on it.
Remove all code predicated on Xenial or Stretch. debathena support
was migrated to Bionic, since that appears to be the current state of
existing debathena servers.
This prevents memcached from automatically appending the hostname to
the username, which was a source of problems on servers where the
hostname was changed.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
We would prefer to use the postgres packages from Postgres themselves,
if available. However, this requires ensures that, for existing
installs, we preserve the same version of postgres as their base
distribution installed.
Move the version-determination logic from being computed at puppet
interpolation time, to being computed at install time and pinned into
zulip.conf.
Since 9e8f1aacb3, zulip_ops machines
might have two Package declarations for `certbot`, which doesn't work
in puppet.
The fix is, as usual, to use our `zulip::safepackage` wrapper instead.
The style guide for Zulip is to always use "primary" and "replica"
when describing database replication. Adjust a few comments under
`puppet/` that do not adhere to this.
Unfortunately, some references still remain to the insensitive and
inaccurate "master" / "slave" terminology. However, these are only in
files which we are attempting to preserve as close to the upstream
versions they are derived from (e.g. postgresql.conf,
postfix/master.cf).
65774e1c4f switched from using the bundled check_postgres.pl to using
the version from packages; the file itself remained, however.
Remove it, and clean up references to it.
Fixes#15389.
Instead of SSH'ing around to them, run directly on the database hosts.
This means that the replicas do not know how many bytes behind they
are in _receiving_ the wall logs; thus, the monitoring also extends to
the primary database, which knows that information for each replica.
This also allows for detecting when there are too few active replicas.
Use read-only types (List ↦ Sequence, Dict ↦ Mapping, Set ↦
AbstractSet) to guard against accidental mutation of the default
value.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
All differences between the primary and replica roles having been
merged, fold the `postgres_common`, `postgres_master`, and
`postgres_slave` roles into just `postgres_appdb`.
These values differed between the primary and secondary database
hosts, for unclear reasons. The differences date back to their
introduction in 387f63deaa. As the comment in the replica
confguration notes, settings of `vm.dirty_ratio = 10` and
`vm.dirty_background_ratio = 5` matched the kernel defaults for
"newer" kernels; however, kernel 2.6.30 bumped those to 20 and 10,
respectively[1], as a fix for underlying logic now being more correct.
Remove these overrides; they should at very least be consistent across
roles, and the previous values look to be an attempt to tune for a
very much older version of the Linux kernel, which was using an
different, buggier, algorithm under the hood.
[1] 1b5e62b42b
This file controls streaming replication, and recovery using wal-g on
the secondary. The `primary_conninfo` data needs to change on short
notice when database failover happens, in a way that is not suitable
for being controlled by puppet.
PostgreSQL 12, in fact, removes the use of the `recovery.conf` file[1];
the `primary_conninfo` and `restore_command` information goes into the
main `postgresql.conf` file, and the standby status is controlled by
the presence of absence of an empty `standby.signal` file.
Remove the puppet control of the `recovery.conf` file.
[1] https://pgstef.github.io/2018/11/26/postgresql12_preview_recovery_conf_disappears.html
Since the nagios authentication is stored _in the database_, it is
unnecessary to run if the database is simply a replica of the
production database. The only case in which this statement would have
an effect is if the postgres node contains a _different_ (or empty)
database, which `setup_disks` now effectively prevents.
Remove the unnecessary step.
481613a344 updated the `setup_disks` script to no longer reference
`mdadm`, since we no longer set up RAID on servers.
Update the puppet that would call it to remove the `mdadm` dependency,
and run only if the state is not what it produces -- namely, a symlink
for `/var/lib/postgresql`, which must point to an existent
`/srv/postgresql` directory.
The end state it produces is _either_:
- `/srv/postgresql` already existed, which was symlinked into
`/var/lib/postgresql`; postgres is left untouched. This is the
situation if `setup_disks` is run on the database primary, or a
replica which was correctly configured.
- An empty `/srv/postgresql` now exists, symlinked into
`/var/lib/postgresql`, and postgres is stopped. This is the
situation if `puppet` was just run on a new host, or a
previously-configured host was rebooted (clearing the temporary
disk in `/dev/nvme0`)
In the latter case, where `/srv/postgresql` is now empty, any previous
contents of `/var/lib/postgresql` are placed under `/root`,
timestamped for uniqueness.
In either case, the tool should now be idempotent.
This fixes errors when provisioning a new system (or version of
postgres) when the configuration file cannot be written because its
parent directories do not exist.
Files inherently depend on their containing directories, so no
explicit dependencies are necessary.
The `pg_datadir` variable was only used, and accurate, for CentOS.
Pull it out into `postgres_app_base`, broaden it to being accurate on
Debian-based systems as well, and use it consistently in the
templates.
As the previous commit, this is currently only used in tuning, but is
a property of the whole postgres configuration; move it there, as just
the directory, not the file.
Use this directory consistently in the erb templates. Since we
produce a `pg_hba.conf`, it makes sense that we point to the path that we
know that we explicitly wrote to, for instance.
While it is only currently used in the tuning configuration, it is a
property of the base configuration, and fits more clearly into the
case block there.
Fixes#2665.
Regenerated by tabbott with `lint --fix` after a rebase and change in
parameters.
Note from tabbott: In a few cases, this converts technical debt in the
form of unsorted imports into different technical debt in the form of
our largest files having very long, ugly import sequences at the
start. I expect this change will increase pressure for us to split
those files, which isn't a bad thing.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
Automatically generated by the following script, based on the output
of lint with flake8-comma:
import re
import sys
last_filename = None
last_row = None
lines = []
for msg in sys.stdin:
m = re.match(
r"\x1b\[35mflake8 \|\x1b\[0m \x1b\[1;31m(.+):(\d+):(\d+): (\w+)", msg
)
if m:
filename, row_str, col_str, err = m.groups()
row, col = int(row_str), int(col_str)
if filename == last_filename:
assert last_row != row
else:
if last_filename is not None:
with open(last_filename, "w") as f:
f.writelines(lines)
with open(filename) as f:
lines = f.readlines()
last_filename = filename
last_row = row
line = lines[row - 1]
if err in ["C812", "C815"]:
lines[row - 1] = line[: col - 1] + "," + line[col - 1 :]
elif err in ["C819"]:
assert line[col - 2] == ","
lines[row - 1] = line[: col - 2] + line[col - 1 :].lstrip(" ")
if last_filename is not None:
with open(last_filename, "w") as f:
f.writelines(lines)
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
1f565a9f41 removed the `package` lines which install
`python-dateutil`, but not the line in `puppet_ops` that reference it;
as such, Puppet manifests in puppet_ops fail to compile.
Remove the stale reference to `python-dateutil`, which is unnecessary
since the code is python3, not python2.
The zulip user needs to be able to read the file, when running the
backup tool.
We put root:root as owner on other nginx config files, so it's probably
correct to keep the ownership as it is, and set the mode to 0644.
certbot-auto doesn’t work on Ubuntu 20.04, and won’t be updated; we
migrate to instead using the certbot package shipped with the OS
instead. Also made sure that sure certbot gets installed when running
zulip-puppet-apply, to handle existing systems.
We're migrating to using the cleaner zulip.com domain, which involves
changing all of our links from ReadTheDocs and other places to point
to the cleaner URL.
datetime.timezone is available in Python ≥ 3.2. This also lets us
remove a pytz dependency from the PostgreSQL scripts.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
This is vestigial.
It requires manually altering the `htdigest` file (not stored in this
repo) to change the digest realm from `wiki` to `monitoring`, and will
re-prompt users for their passwords if the browsers currently store
them.
Drop the change to move `/tmp` onto the local disk. Doing this move
confuses `resolved` until there is a restart, and has no clear
benefits. The change came in during bf82fadc95, but does not describe
the reasoning; it is particularly puzzling, since postgresql stores
its temporary files under `$PGDATA/base/pgsql_tmp`.
Do not RAID the disks together. This was previously done when they
were spinning media, for reliability; running them on an SSD obviates
this sufficiently. This means that updating the initramfs is also not
necessary.
This no longer has any rules specific to it. We leave the `postgres`
munin group (which now only contains `postgres_appdb`) as
future-proofing, and so that `postgres_appdb` matches to the puppet
manifest of the same name.
This allows straight-forward configuration of realm-based Tornado
sharding through simply editing /etc/zulip/zulip.conf to configure
shards and running scripts/refresh-sharding-and-restart.
Co-Author-By: Mateusz Mandera <mateusz.mandera@zulip.com>
memcached 1.5.22 in Ubuntu 20.04 has a bug where it looks for its SASL
configuration at /etc/sasl2/memcached.conf/memcached.conf instead of
/etc/sasl2/memcached.conf.
https://bugs.launchpad.net/ubuntu/+source/memcached/+bug/1878721
Signed-off-by: Anders Kaseorg <anders@zulip.com>
Using the `host` virtual package confused Puppet into reporting it was
doing work every time one did a puppet run, resulting in unnecessarily
spammy output.
While this functionality to post slow queries to a Zulip stream was
very useful in the early days of Zulip, when there were only a few
hundred accounts, it's long since been useless since (1) the total
request volume on larger Zulip servers run by Zulip developers, and
(2) other server operators don't want real-time notifications of slow
backend queries. The right structure for this is just a log file.
We get rid of the queue and replace it with a "zulip.slow_queries"
logger, which will still log to /var/log/zulip/slow_queries.log for
ease of access to this information and propagate to the other logging
handlers. Reducing the amount of queues is good for lowering zulip's
memory footprint and restart performance, since we run at least one
dedicated queue worker process for each one in most configurations.
Our priority hierarchy is:
(1) Tornado and base services like memcached, redis, etc.
(2) Django and message sender queue workers.
(3) Everything else.
Ideally, we'd have something a bit more fine-grained (e.g. some queue
workers are potentially in the sending path, while others aren't), but
this should have a big impact on ensuring Tornado gets the resources
it needs during load spikes.
I think this has a good chance of causing some load spikes that would
previously have resulted in a user-facing delivery delays no longer
having any significant user-facing impact.
Currently when the user uploads files with ".jpe" file extension, the
markdown is converted to link but the image is not embedded.
This commit adds the support for ".jpe" file extension.
Fixes#14863
We could anchor the regexes, but there’s no need for the power (and
responsibility) of regexes here.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
This PR updates the puppet manifest to allow /etc/zulip to be a symlink. The current behaviour overwrites /etc/zulip if it is link to another directory, which is problematic with docker-zulip and
in particular the `LINK_SETTINGS_TO_DATA` setting.
Generated by `pyupgrade --py3-plus --keep-percent-format` on all our
Python code except `zthumbor` and `zulip-ec2-configure-interfaces`,
followed by manual indentation fixes.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
The nginx ‘add_header’ directive doesn’t inherit the way you’d
want (https://trac.nginx.org/nginx/ticket/854), so we need to manually
simulate inheritance using ‘include’, like we previously did with
api_headers.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
isort 5 knows not to reorder imports across function calls, so this
will stop isort from breaking our code.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
Puppet doesn’t re-run an exec blocks that’s declared as creating an
existing file, even if it’s notified. Remove the creates declaration.
Fixes#13730.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
"Zulip Voyager" was a name invented during the Hack Week to open
source Zulip for what a single-system Zulip server might be called, as
a Star Trek pun on the code it was based on, "Zulip Enterprise".
At the time, we just needed a name quickly, but it was never a good
name, just a placeholder. This removes that placeholder name from
much of the codebase. A bit more work will be required to transition
the `zulip::voyager` Puppet class, as that has some migration work
involved.
This legacy cross-realm bot hasn't been used in several years, as far
as I know. If we wanted to re-introduce it, I'd want to implement it
as an embedded bot using those common APIs, rather than the totally
custom hacky code used for it that involves unnecessary queue workers
and similar details.
Fixes#13533.
Zulip has had a small use of WebSockets (specifically, for the code
path of sending messages, via the webapp only) since ~2013. We
originally added this use of WebSockets in the hope that the latency
benefits of doing so would allow us to avoid implementing a markdown
local echo; they were not. Further, HTTP/2 may have eliminated the
latency difference we hoped to exploit by using WebSockets in any
case.
While we’d originally imagined using WebSockets for other endpoints,
there was never a good justification for moving more components to the
WebSockets system.
This WebSockets code path had a lot of downsides/complexity,
including:
* The messy hack involving constructing an emulated request object to
hook into doing Django requests.
* The `message_senders` queue processor system, which increases RAM
needs and must be provisioned independently from the rest of the
server).
* A duplicate check_send_receive_time Nagios test specific to
WebSockets.
* The requirement for users to have their firewalls/NATs allow
WebSocket connections, and a setting to disable them for networks
where WebSockets don’t work.
* Dependencies on the SockJS family of libraries, which has at times
been poorly maintained, and periodically throws random JavaScript
exceptions in our production environments without a deep enough
traceback to effectively investigate.
* A total of about 1600 lines of our code related to the feature.
* Increased load on the Tornado system, especially around a Zulip
server restart, and especially for large installations like
zulipchat.com, resulting in extra delay before messages can be sent
again.
As detailed in
https://github.com/zulip/zulip/pull/12862#issuecomment-536152397, it
appears that removing WebSockets moderately increases the time it
takes for the `send_message` API query to return from the server, but
does not significantly change the time between when a message is sent
and when it is received by clients. We don’t understand the reason
for that change (suggesting the possibility of a measurement error),
and even if it is a real change, we consider that potential small
latency regression to be acceptable.
If we later want WebSockets, we’ll likely want to just use Django
Channels.
Signed-off-by: Anders Kaseorg <anders@zulipchat.com>
Alex Vandiver
Anders Kaseorg
Tim Abbott
Casper Kvan Clausen
Mateusz Mandera
rht
Alex Vandiver
Anders Kaseorg
arpit551
Tim Abbott
Mateusz Mandera
shubhamgupta2956
Aman Agrawal
pemontto
Vishnu KS
Stefan Weil