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A screamingly fast Python 2 + 3 WSGI server written in C.

Project description

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A screamingly fast, ultra-lightweight WSGI server for CPython 2 and CPython 3, written in C using Marc Lehmann’s high performance libev event loop and Ryan Dahl’s http-parser.

Why It’s Cool

bjoern is the fastest, smallest and most lightweight WSGI server out there, featuring

  • ~ 1000 lines of C code

  • Memory footprint ~ 600KB

  • Python 2 and Python 3 support (thanks @yanghao!)

  • Single-threaded and without coroutines or other crap

  • Can bind to TCP host:port addresses and Unix sockets (thanks @k3d3!)

  • Full persistent connection (”keep-alive”) support in both HTTP/1.0 and 1.1, including support for HTTP/1.1 chunked responses


pip install bjoern. See wiki for details.


Flask example

from flask import Flask

app = Flask(__name__)

def hello_world():
    return "Hello, World!"

if __name__ == "__main__":
    import bjoern, "", 8000)

Advanced usage

# Bind to TCP host/port pair:, host, port)

# TCP host/port pair, enabling SO_REUSEPORT if available., host, port, reuse_port=True)

# Bind to Unix socket:, 'unix:/path/to/socket')

# Bind to abstract Unix socket: (Linux only), 'unix:@socket_name')

# Enable statsd metrics. See for details., host, port, statsd=...)

Alternatively, the mainloop can be run separately:

bjoern.listen(wsgi_application, host, port)

# With metrics. See for details.
bjoern.listen(wsgi_application, host, port)

You can also simply pass a Python socket(-like) object. Note that you are responsible for initializing and cleaning up the socket in that case.

bjoern.server_run(socket_object, wsgi_application)
bjoern.server_run(filedescriptor_as_integer, wsgi_application)

# This needs manual compilation with `WANT_STATSD=yes`
bjoern.server_run(socket_object, wsgi_application, enable_statsd=True)

Project details

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bjoern-3.2.2.tar.gz (45.7 kB view hashes)

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