Middleware for Starlette that allows you to store and access the context data of a request. Can be used with logging so logs automatically use request headers such as x-request-id or x-correlation-id.

$ pip install starlette-context

Python 3.7+

For Python 3.6 only:
contextvar came out with python3.7 and is required for this to run. If you need to use Starlette with python3.6, there is a backport of contextvar for py36. https://github.com/MagicStack/contextvars

• starlette

All other dependencies from requirements-dev.txt are only needed to run tests or examples. Test/dev env is dockerized if you want to try them yourself.

from starlette.applications import Starlette
from starlette.middleware import Middleware
from starlette.requests import Request
from starlette.responses import JSONResponse

import uvicorn
from starlette_context import context, plugins
from starlette_context.middleware import ContextMiddleware

middleware = [
    Middleware(
        ContextMiddleware,
        plugins=(
            plugins.RequestIdPlugin(),
            plugins.CorrelationIdPlugin()
        )
    )
]

app = Starlette(middleware=middleware)


@app.route("/")
async def index(request: Request):
    return JSONResponse(context.data)


uvicorn.run(app, host="0.0.0.0")

In this example the response contains a json with

{
  "X-Correlation-ID":"5ca2f0b43115461bad07ccae5976a990",
  "X-Request-ID":"21f8d52208ec44948d152dc49a713fdd"
}

Context can be updated and accessed at anytime if it's created in the middleware.

All tickets or PRs are more than welcome.