How to Run Python Apps on Apache with mod_wsgi Module

Mod_wsgi is an Apache HTTP Server module by Graham Dumpleton that provides a WSGI compliant interface for hosting Python based web applications. It is written in C codes. So it has better performance and lower memory overhead than mod_python or others.

This tutorial will teach you how to run python scripts on Apache with mod_wsgi module on Ubuntu and Centos.

Step 1) Install Apache2, Python and mod_wsgi

Lets first install apache, python, and mod_wsgi packages on Linux.

On Ubuntu

The latest version of Ubuntu comes with python installed, if you looking to install a specific version run the following command.

$ sudo apt install python3.7 -y

Install apache2 on ubuntu 18.04

$ sudo apt install apache2 apache2-utils ssl-cert

Install mod_wsgi using the following command:

$ sudo apt-get install libapache2-mod-wsgi

On CentOS

On CentOS, we can use yum command to install packages.

Install Apache

$ sudo yum install httpd

The following command will install python 3.6 on CentOS.

$ sudo yum install rh-python36

Install mod_wsgi

# yum install mod_wsgi

Step 2) Configure Apache with mod_wsgi

Modify the '/etc/httpd/conf/httpd.conf' file and add below line in the 'LoadModule' section:

LoadModule wsgi_module modules/mod_wsgi.so

After updating the configuration file restart apache webserver.

Maybe you don't need to modify 'httpd.conf' file, if there is /etc/httpd/conf.d/wsgi.conf.

Step 3) Create web access directory and python file

For example, create '/usr/local/wsgi/scripts' directory and add 'wsgi-myapp.py' file in it.

File content is as follows:

def application(environ,start_response):
status='200 OK'
output='Hello world'
response_headers=[('Content-type','text/plain'),
('Content-Length',str(len(output)))]
start_response(status,response_headers)
return [output]

step 4) Create Apache conf file

Create a file named 'myapp.conf' and put it in the '/etc/httpd/conf.d/' directory. The file content is:

Alias /myapp “/usr/local/wsgi/scripts/wsgi-myapp.py”

Options ExecCGI
SetHandler wsgi-script
Order allow,deny
Allow from all

Step 5) Check the result

Now restart httpd service. Then open Firefox and input address 'localhost/myapp', you will see 'Hello world' in the web page.

Related: How to Setup Python Virtual Environment on Ubuntu 18.04