I have read FastAPI's documentation about middlewares (specifically, the middleware tutorial, the CORS middleware section and the advanced middleware guide), but couldn't find a concrete example of how to write a middleware class which you can add using the add_middleware function (in contrast to a basic middleware function added using a decorator) there nor on this site. The reason I prefer to use add_middleware over the app based decorator, is that I want to write a middleware in a shared library that will be used by several different projects, and therefore I can't tie it to a specific FastAPI instance. So my question is: how do you do it? Continue reading...
