SwitchFlow is an experimental HTTP reverse proxy in C++

SwitchFlow is an experimental HTTP reverse proxy in C++. I started the project in 2003 and was influenced by Dan Kegel's C10k problem. Because of this the server is single threaded, event driven and uses Niels Provos's Libevent for event aggregation.

The project was shelved in 2007 after Nginx gained traction, but I recently cleaned up the tree and got the proxy building on Ubuntu 12.04.

It can be used to configure virtual hosts and send requests to multiple origin servers.

Quick build guide

# Install dependencies
sudo apt-get install libevent-dev libboost-all-dev cmake build-essential
# run script to configure build environment using cmake
source ./configbuild.sh
# build the proxy
cd release/sfrp
make

Configuring the proxy

The proxy uses a simple key/value pair configuration file. The configuration file also supports records and arrays of values. It is new line delimited. An example configuration file included in the tree at /sfrp/app/sfrp.conf.example.

# Directs the proxy to detach from the console and run as a daemon
proxy.run-as-daemon=no

# This is the address the proxy will listen on
proxy.listen-address[0].address=127.0.0.1
proxy.listen-address[0].port=8080

# This is the address the proxy will forward requests to
# by default.
proxy.default-forward-address.address=204.232.175.78
proxy.default-forward-address.port=80

# Enable apache combined style access logging.
access-log.enable=yes
access-log.location=/var/log/sfrp_access_log_stage

# The following shows how to describe virtual hosts

# host-name is the value sent by the client in the host HTTP header.
virtual-host[0].host-name=localhost:8080

# This is the URL to send requests which match the example.com host
# to.  The specified URL path is prepended to incoming requests' paths.
virtual-host[0].default-forward-url=http://baus.net

# This tells the proxy to send the request's host to server, rather than
# replace the host with server's host.  In this case 127.0.0.1 will
# receive a host of example.com.  In other cases it might be useful
# to pass the name 
virtual-host[0].preserve-host=false


# The following are used to performance tune
# the HTTP parser's memory usage.  You probably
# don't need to change these unless you have
# specific requirements.
http-parser.max-method-length=256
http-parser.max-URI-length=512
http-parser.max-num-headers=50
http-parser.max-header-name-length=256
http-parser.max-header-value-length=512
http-parser.header-pool-size=75000
proxy.input-buffer-size=2000

#
# The user name to switch to after starting the proxy and binding to
# server socket.
proxy.user=nobody

#
# The following configure the proxy's connection
# handling.
proxy.client-timeout-milliseconds=30000
proxy.server-timeout-milliseconds=10000
proxy.max-connections=1000 

from https://github.com/baus/switchflow