Previous to this change our anonymous rate limits acted as a throttle.
New implementation means we now also consider rate limited requests towards
the limit.
This means that if an anonymous user is hammering the server it will not be
able to get any requests through until it subsides with traffic.
Non UTF-8 user_agent requests were bypassing logging due to PG always
wanting UTF-8 strings.
This adds some conversion to ensure we are always dealing with UTF-8
This allows custom plugins such as prometheus exporter to log how many
requests are stored in the anon cache vs used by the anon cache.
This metric allows us to fine tune cache behaviors
The message_bus performs a fair amount of work prior to hijacking requests
this change ensures that if there is a situation where the server is flooded
message_bus will inform client to back off for 30 seconds + random(120 secs)
This back-off is ultra cheap and happens very early in the middleware.
It corrects a situation where a flood to message bus could cause the app
to become unresponsive
MessageBus update is here to ensure message_bus gem properly respects
Retry-After header and status 429.
Under normal state this code should never trigger, to disable raise the
value of DISCOURSE_REJECT_MESSAGE_BUS_QUEUE_SECONDS, default is to tell
message bus to go away if we are queueing for 100ms or longer
This adds support for DISCOURSE_ENABLE_PERFORMANCE_HTTP_HEADERS
when set to `true` this will turn on performance related headers
```text
X-Redis-Calls: 10 # number of redis calls
X-Redis-Time: 1.02 # redis time in seconds
X-Sql-Commands: 102 # number of SQL commands
X-Sql-Time: 1.02 # duration in SQL in seconds
X-Queue-Time: 1.01 # time the request sat in queue (depends on NGINX)
```
To get queue time NGINX must provide: HTTP_X_REQUEST_START
We do not recommend you enable this without thinking, it exposes information
about what your page is doing, usually you would only enable this if you
intend to strip off the headers further down the stream in a proxy
By default, this does nothing. Two environment variables are available:
- `DISCOURSE_LOG_SIDEKIQ`
Set to `"1"` to enable logging. This will log all completed jobs to `log/rails/sidekiq.log`, along with various db/redis/network statistics. This is useful to track down poorly performing jobs.
- `DISCOURSE_LOG_SIDEKIQ_INTERVAL`
(seconds) Check running jobs periodically, and log their current duration. They will appear in the logs with `status:pending`. This is useful to track down jobs which take a long time, then crash sidekiq before completing.
This avoids require dependency on method_profiler and anon cache.
It means that if there is any change to these files the reloader will not pick it up.
Previously the reloader was picking up the anon cache twice causing it to double load on boot.
This caused warnings.
Long term my plan is to give up on require dependency and instead use:
https://github.com/Shopify/autoload_reloader
Detailed request loggers can be used to gather rich timing info
from all requests (which in turn can be forwarded to monitoring solution)
Middleware::RequestTracker.detailed_request_logger(->|env, data| do
# do stuff with env and data
end
