Starlette Cramjam

0.7.0 verified Mon Apr 27 auth: no python

Middleware that adds compression (gzip, brotli, zstd, deflate) to Starlette ASGI applications using the cramjam library. Version 0.7.0; releases are irregular.

pip install starlette-cramjam

Common errors

error ImportError: cannot import name 'CompressMiddleware' from 'starlette_cramjam' ↓

cause The class is in the .middleware submodule, not in __init__.py.

fix

Use: from starlette_cramjam.middleware import CompressMiddleware

error Compression not applied to 204 No Content responses ↓

cause Version 0.7.0 intentionally skips compression for 204 responses to avoid breaking RFC 7231.

fix

If you must compress 204, downgrade to <0.7.0 or modify middleware source.

Warnings

breaking Python 3.9 and 3.10 support dropped in version 0.6.0; requires Python >=3.11. ↓

fix Upgrade Python to 3.11+ or pin to starlette-cramjam <0.6.0.

gotcha The middleware may skip compression for small responses based on default minimum size (min_size). Responses smaller than 500 bytes are not compressed. ↓

fix Set min_size=0 in CompressMiddleware(min_size=0) to compress all responses.

Imports

CompressMiddleware
wrong
```
from starlette_cramjam import CompressMiddleware
```
correct
```
from starlette_cramjam.middleware import CompressMiddleware
```
CompressMiddleware is not exported from __init__.py; must import from .middleware submodule.

Quickstart

Basic Starlette app with compression middleware enabled.

from starlette.applications import Starlette
from starlette.responses import PlainTextResponse
from starlette.routing import Route
from starlette_cramjam.middleware import CompressMiddleware

async def hello(request):
    return PlainTextResponse("Hello, World!")

app = Starlette(routes=[Route('/', hello)])
app.add_middleware(CompressMiddleware)