This saves about 8% of the runtime of our total response middleware,
or equivalently close to 2% of the total Tornado response time. Which
is pretty significant given that we're not sure anyone is using statsd
in production.
It's also useful outside Tornado, but the effect is particularly
significant because of how important Tornado performance is.
This avoids parsing these functions on every request, which was
adding roughly 350us to our per-request response times.
The overall impact was more than 10% of basic Tornado response
runtime.
Our html collects extra spaces in a couple of places. The most prominent is
paragraphs that look like the following in the .md file:
* some text
continued
The html will have two spaces before "continued".
Refactor the potentially expensive work done by Beautiful Soup into a
function that is called by the alter_content function, so that we can
cache the result. Saves a significant portion of the runtime of
loading of all of our /help/ and /api/ documentation pages (e.g. 12ms
for /api).
Fixes#11088.
Tweaked by tabbott to use the URL path as the cache key, clean up
argument structure, and use a clearer name for the function.
This is somewhat hacky, in that in order to do what we're doing, we
need to parse the HTML of the rendered page to extract the first
paragraph to include in the open graph description field. But
BeautifulSoup does a good job of it.
This carries a nontrivial performance penalty for loading these pages,
but overall /help/ is a low-traffic site compared to the main app, so
it doesn't matter much.
(As a sidenote, it wouldn't be a bad idea to cache this stuff).
There's lots of things we can improve in this, largely through editing
the articles, but we can deal with that over time.
Thanks to Rishi for writing all the tests.
Until we resolve https://github.com/zulip/zulip/issues/10832, we will
need to maintain our own forked copy of Django's SessionMiddleware.
We apparently let this get out of date.
This fixes a few subtle bugs involving the user logout experience that
were throwing occasional exceptions (e.g. the UpdateError fix you can
see).
Apparently, we weren't resetting the query counters inside the
websockets codebase, resulting in broken log results like this:
SOCKET 403 2ms (db: 1ms/2q) /socket/auth [transport=websocket] (unknown via ?)
SOCKET 403 5ms (db: 2ms/3q) /socket/auth [transport=websocket] (unknown via ?)
SOCKET 403 2ms (db: 3ms/4q) /socket/auth [transport=websocket] (unknown via ?)
SOCKET 403 2ms (db: 3ms/5q) /socket/auth [transport=websocket] (unknown via ?)
SOCKET 403 2ms (db: 4ms/6q) /socket/auth [transport=websocket] (unknown via ?)
SOCKET 403 2ms (db: 5ms/7q) /socket/auth [transport=websocket] (unknown via ?)
SOCKET 403 2ms (db: 5ms/8q) /socket/auth [transport=websocket] (unknown via ?)
SOCKET 403 3ms (db: 6ms/9q) /socket/auth [transport=websocket] (unknown via ?)
The correct fix for this is to call reset_queries at the start of each
endpoint within the websockets system. As it turns out, we're already
calling record_request_start_data there, and in fact should be calling
`reset_queries` in all code paths that use that function (the other
code paths, in zerver/middleware.py, do it manually with
connection.connection.queries = []).
So we can clean up the code in a way that reduces risk for similar
future issues and fix this logging bug with this simple refactor.
Previously, these timer accounting functions could be easily mistaken
for referring to starting/stopping the request. By adding timer to
the name, we make the code easier for the casual observer to read and
understand.
When our code raises an exception and Django converts it to a 500
response (in django.core.handlers.exception.handle_uncaught_exception),
it attaches the request to the log record, and we use this in our
AdminNotifyHandler to include data like the user and the URL path
in the error email sent to admins.
On this line, when our code raises an exception but we've decided (in
`TagRequests`) to format any errors as JSON errors, we suppress the
exception so we have to generate the log record ourselves. Attach the
request here, just like Django does when we let it do the job.
This still isn't an awesome solution, in that there are lots of other
places where we call `logging.error` or `logging.exception` while
inside a request; this just covers one of them. This is one of the
most common, though, so it's a start.
Originally this used signals, namely SIGRTMIN. But in prod, the
signal handler never fired; I debugged fruitlessly for a while, and
suspect uwsgi was foiling it in a mysterious way (which is kind of
the only way uwsgi does anything.)
So, we listen on a socket. Bit more code, and a bit trickier to
invoke, but it works.
This was developed for the investigation of memory-bloating on
chat.zulip.org that led to a331b4f64 "Optimize query_all_subs_by_stream()".
For usage instructions, see docstring.
These are just instances that jumped out at me while working on the
subdomains code, mostly while grepping for get_subdomain call sites.
I haven't attempted a comprehensive search, and there are likely
still others left.
We originally wrote this because when testing subdomains, you wanted
to be sure you were actually testing subdomains. Now that subdomains
is the default, doesn't seem to actually be a good reason why we
should need this.
Previously, this would always send one to homepage, making visiting
the /help/ documentation in the development environment using the
localhost URL unpleasant.
While this fixes the proximal bug, it's not clear to me that we need
this redirect logic at all, so I'm going to try removing it soon.
This allows us to reliably parse the error in code, rather than
attempt to parse the error text. Because the error text gets
translated into the user's language, this error-handling path
wasn't functioning at all for users using Zulip in any of the
seven non-English languages for which we had a translation for
this string.
Together with 709c3b50f which fixed a similar issue in a
different error-handling path, this fixes#5598.
This provides the main infrastructure for fixing #5598. From here,
it's a matter of on the one hand upgrading exception handlers -- the
many except-blocks in the codebase that look for JsonableError -- to
look beyond the string `msg` and pass on the machine-readable full
error information to their various downstream recipients, and on the
other hand adjusting places where we raise errors to take advantage
of this mechanism to give the errors structured details.
In an ideal future, I think all exception handlers that look (or
should look) for a JsonableError would use its contents in structured
form, never mentioning `msg`; but the majority of error sites might
continue to just instantiate JsonableError with a string message. The
latter is the simplest thing to do, and probably most error types will
never have code looking for them specifically.
Because the new API refactors the `to_json_error_msg` method which was
designed for subclasses to override, update the 4 subclasses that did
so to take full advantage of the new API instead.
With #5598 there will soon be an application-level error code
optionally associated with a `JsonableError`, so rename this
field to make clear that it specifically refers to an
HTTP status code.
Also take this opportunity to eliminate most of the places
that refer to it, which only do so to repeat the default value.
In order to benefit from the modern conveniences of type-checking,
add concrete, non-Any types to the interface for JsonableError.
Relatedly, there's no need at this point to duck-type things at
the places where we receive a JsonableError and try to use it.
Simplify those by using straightforward standard typing.
This adds helpful email notifications for users who just logged into a
Zulip server, as a security protection against accounts being hacked.
Text tweaked by tabbott.
Fixes#2182.
Django 1.10 has changed the implementation of this function to
match our custom implementation; in addition to this, we prefer
render().
Fixes#1914 via #4093.