Awesome
brotli-asgi
BrotliMiddleware
adds Brotli response compression to ASGI applications (Starlette, FastAPI, Quart, etc.). It provides faster and more dense compression than GZip, and can be used as a drop in replacement for the GZipMiddleware
shipped with Starlette.
Installation
pip install brotli-asgi
Examples
Starlette
from starlette.applications import Starlette
from starlette.responses import JSONResponse
from starlette.routing import Route
from starlette.middleware import Middleware
from brotli_asgi import BrotliMiddleware
async def homepage(request):
return JSONResponse({"data": "a" * 4000})
app = Starlette(
routes=[Route("/", homepage)],
middleware=[Middleware(BrotliMiddleware)],
)
FastAPI
from fastapi import FastAPI
from brotli_asgi import BrotliMiddleware
app = FastAPI()
app.add_middleware(BrotliMiddleware)
@app.get("/")
def home() -> dict:
return {"data": "a" * 4000}
API Reference
Overview
app.add_middleware(
BrotliMiddleware,
quality=4,
mode="text",
lgwin=22,
lgblock=0,
minimum_size=400,
gzip_fallback=True
)
Parameters:
- (Optional)
quality
: Controls the compression speed vs compression density tradeoff. The higher the quality, the slower the compression. Range is 0 to 11. - (Optional)
mode
: The compression mode can be:"generic"
,"text"
(Default
for UTF-8 format text input) or"font"
(for WOFF 2.0). - (Optional)
lgwin
: Base 2 logarithm of the sliding window size. Range is 10 to 24. - (Optional)
lgblock
: Base 2 logarithm of the maximum input block size. Range is 16 to 24. If set to 0, the value will be set based on the quality. - (Optional)
minimum_size
: Only compress responses that are bigger than this value in bytes. - (Optional)
gzip_fallback
: IfTrue
, uses gzip encoding ifbr
is not in the Accept-Encoding header.
Notes:
- It won't apply Brotli compression on responses that already have a Content-Encoding set, to prevent them from being encoded twice.
- If the GZip fallback is applied, and the response already had a Content-Encoding set, the double-encoding-prevention will only happen if you're using Starlette
>=0.22.0
(see the PR).
Performance
To better understand the benefits of Brotli over GZip, see, Gzip vs. Brotli: Comparing Compression Techniques, where detailed information and benchmarks are provided.
A simple comparative example using Python sys.getsizof()
and timeit
:
# ipython console
import gzip
import sys
import brotli
import requests
page = requests.get("https://github.com/fullonic/brotli-asgi").content
%timeit brotli.compress(page, quality=4)
# 1.83 ms ± 43 µs per loop (mean ± std. dev. of 7 runs, 1000 loops each)
sys.getsizeof(brotli.compress(page, quality=4))
# 20081
%timeit gzip.compress(page, compresslevel=6)
# 2.75 ms ± 29.8 µs per loop (mean ± std. dev. of 7 runs, 100 loops each)
sys.getsizeof(gzip.compress(page, compresslevel=6))
# 20640
Compatibility
According to caniuse.com, Brotli is supported by all major browsers with a global use of over 96.3%.