How to read all HTTP headers in Python CGI script?

PythonServer Side ProgrammingProgrammingCGI

It is possible to get a custom request header's value in an apache CGI script with python. The solution is similar to this.

Apache's mod_cgi will set environment variables for each HTTP request header received, the variables set in this manner will all have an HTTP_ prefix, so for example x-client-version: 1.2.3 will be available as variable HTTP_X_CLIENT_VERSION.

So, to read the above custom header just call os.environ["HTTP_X_CLIENT_VERSION"].

The below script will print all HTTP_* headers and values −

#!/usr/bin/env python

import os
print "Content-Type: text/html"
print "Cache-Control: no-cache"

print "<html><body>"
for headername, headervalue in os.environ.iteritems():
    if headername.startswith("HTTP_"):
        print "<p>{0} = {1}</p>".format(headername, headervalue)
print "</html></body>"
Published on 18-Feb-2018 08:37:49