nginx2cgi

This project is a small Perl script you can include in your nginx config to enable running CGI scripts directly from nginx (no need to run a separate FastCGI or fcgiwrap or uWSGI process).

How to use

1. Install the nginx Perl module.

apt install libnginx-mod-http-perl

2. Include cgi.nginx.conf from this repo in your nginx config for whatever location you want CGI to be used, and set the variable $cgi_script to be called (and optionally $cgi_headers to specify which headers to pass to your CGI script).

location /mycgi {
    set $cgi_script "/path/to/cgi-bin/myscript.cgi";
    set $cgi_headers "Host Content-Length Content-Type Cookie Authorization";
    include "/path/to/cgi.nginx.conf";
}

How this works

The included config is a small Perl script that converts the incoming request into a CGI request, calls the designated $cgi_script path as a subprocess, and returns whatever the result is as the response.

NOTE: The Perl script uses open2 to call the $cgi_script for every request, which means this briefly forks and creates a new subprocess for every request. So this project is not nearly as efficient as running a dedicated FastCGI server. I made this project primarily for low volume dynamic websites where I didn't want to have to run an additional server besides nginx.

Example: Run a Python wsgi app via CGI

/path/to/myapp.py:

def app(environ, start_response):
    resp_body = b"Hello World!"
    start_response("200 OK", [
        ('Content-Type', "text/plain"),
        ('Content-Length', str(len(resp_body))),
    ])
    return [resp_body]

/etc/nginx/sites-enabled/mydemo.conf:

server {
    listen 8000;

    location / {
        set $cgi_script "cd /path/to/ && python3 -c 'import myapp, wsgiref.handlers; wsgiref.handlers.CGIHandler().run(myapp.app)'";
        include "/path/to/cgi.nginx.conf";
    }
}