Talisker is designed with the following high level goals:
to provide a standard platform for running wsgi apps
to support both operational and developer workflows in the same tool
to be easy as possible to integrate with any wsgi app and framework
The original motivation was to standardise tooling across a number of different wsgi services, and improve the status quo along the way. Some of the inspiration came from Finagle, Twitter’s service framework for the JVM, particularly the operational standardisation it provides.
In particular, we wanted to standardise how we monitor applications in production, including logging, metrics, errors and alerts. Talisker provides a single library to do this for all our apps, that our operations tooling can configure easily, and means the application doesn’t need to care about it.
Also we wanted to provide best practice features for applications to use. So we added support for structured logging, integrated with the python stdlib logging. This allows developers to add custom tags to their logs, as well as add operational tags. We also provide easy to use helpers for best practice usage of things like statsd clients and requests sessions, which were used inconsistently across our projects, with repeated performance problems.
Some questions that have actually been asked, if not particularly frequently.
Why does talisker use a custom entry point? Wouldn’t it be better to just be some WSGI middleware?
There are 3 reasons for using a talisker specific entry point
to configure stdlib logging early, before any loggers are created
to allow for easy configuration of gunicorn for logging, statsd and other things.
to do things like automatically wrap your wsgi in app in some simple standard middleware, to provide request id tracing and other things.
If it was just middleware, logging would get configured too late for gunicorn’s logs to be affected, and you would need to add explicit middleware and config to your app and its gunicorn config. Doing it as an alternate entry point means you literally just switch out gunicorn for talisker, and you are good to go.
Why just gunicorn? Why not twistd, or waitress, etc?
Simply because we use gunicorn currently. Integrating with other wsgi application runners is totally possible, twistd support is in the works, with uwsgi support on the road map.
Why is it called talisker?
‘WSGI’ sort of sounds like ‘whisky’ if you say it quick. One of my favourite whiskies is Talisker, I’ve even visited the distillery on the Isle of Skye. Also, Talisker is a heavily peated malt whisky, which is not to everyone’s taste, which seemed to fit thematically with a WSGI runtime that is also very opinionated and probably not to everyone’s taste. Also, it has 8 characters just like gunicorn, and it wasn’t taken on PyPI.