feat(starlette): add Starlette integration

[sl0thentr0py]

Integration for the Starlette Framwork: https://www.starlette.io/

Following features are implemented:

• Transaction naming (url style and endpoint style)
• Catch all exceptions from exceptions middleware
• Get user information from auth middleware
• RequestExtractor to get cookie, form, json, raw body data from request
• Middleware Spans for cool waterfall charts in performance

Missing (will be done in a later release):

• distributed tracing in background tasks
• Jinja templates integration

Closes #1463

[github-actions]

This pull request has gone three weeks without activity. In another week, I will close it.

But! If you comment or otherwise update it, I will reset the clock, and if you label it Status: Backlog or Status: In Progress, I will leave it alone ... forever!

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"A weed is but an unloved flower." ― Ella Wheeler Wilcox 🥀

[tiangolo]

This is awesome! 🚀

Just a couple of minor comments for the future.

[tiangolo]

The Starlette base middleware will probably change to fix a couple of issues, and this logic to build the middleware stack will probably change in the future. But I would expect the new version should be easier to patch too.

[antonpirker]

Good to know. (And yes, it was a bit cumbersome to instrument the middlewares :-) )
Any plans on when this will change?

[tiangolo]

Not sure yet because it will probably have to be fixed in Starlette. There are several people trying to solve it, I still have to help review all that too. And then port/update it in FastAPI

[Kludex]

The Starlette base middleware will probably change to fix a couple of issues

What issues? If you mean the BaseHTTPMiddleware yes, but if you mean the build_middleware_stack, there's nothing on Starlette's issues.

EDIT: Reading this again, I think you meant BaseHTTPMiddleware. Which doesn't affect the build_middleware_stack.

[tiangolo]

This is great for Starlette!

For FastAPI, the AuthenticationMiddleware is probably not commonly used because that is handled with dependencies, and there's no predefined expected/standardized user data/model.

It would probably make sense to explain in the docs how to manually and optionally record user data for FastAPI users in dependencies.

[antonpirker]

Good to know. What is the most used dependency for user handling?

We have something in the documentation on how to set the user: https://docs.sentry.io/platforms/python/enriching-events/identify-user/
I will make sure it lands in the FastAPI docs too!

[tiangolo]

That sounds perfect!

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There's not an expected predefined user data model or dependency, so every application can use the data model they find more useful. It normally doesn't require adopting a predefined model or any type of dependency, because installing, learning, and using some package would require the same amount of effort and code as implementing it directly.

The documentation explaining how to handle users is here: https://fastapi.tiangolo.com/tutorial/security/get-current-user/

But again, it's just explaining the concepts, not enforcing a data model.

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I think that documenting how to handle PII in the developers' code, as you suggest with the existing docs, would probably be the best approach here too. Instead of trying to solve it behind the scenes as there's nothing obvious to expect.

[antonpirker]

Good feedback! I will look at your comments tomorrow!

[Kludex]

I don't know how to say this without sounding pedantic, but... Is it possible to change the name of the integration to FastAPIIntegration instead of FastApiIntegration? The name of the framework is FastAPI.