Apache httpd

Apache httpd is a fast, production level HTTP server. When serving your application with one of the WSGI servers listed in Deploying to Production, it is often good or necessary to put a dedicated HTTP server in front of it. This “reverse proxy” can handle incoming requests, TLS, and other security and performance concerns better than the WSGI server.

httpd can be installed using your system package manager, or a pre-built executable for Windows. Installing and running httpd itself is outside the scope of this doc. This page outlines the basics of configuring httpd to proxy your application. Be sure to read its documentation to understand what features are available.

Domain Name

Acquiring and configuring a domain name is outside the scope of this doc. In general, you will buy a domain name from a registrar, pay for server space with a hosting provider, and then point your registrar at the hosting provider’s name servers.

To simulate this, you can also edit your hosts file, located at /etc/hosts on Linux. Add a line that associates a name with the local IP.

Modern Linux systems may be configured to treat any domain name that ends with .localhost like this without adding it to the hosts file.

/etc/hosts

127.0.0.1 hello.localhost

Configuration

The httpd configuration is located at /etc/httpd/conf/httpd.conf on Linux. It may be different depending on your operating system. Check the docs and look for httpd.conf.

Remove or comment out any existing DocumentRoot directive. Add the config lines below. We’ll assume the WSGI server is listening locally at http://127.0.0.1:8000.

/etc/httpd/conf/httpd.conf

LoadModule proxy_module modules/mod_proxy.so
LoadModule proxy_http_module modules/mod_proxy_http.so
ProxyPass / http://127.0.0.1:8000/
RequestHeader set X-Forwarded-Proto http
RequestHeader set X-Forwarded-Prefix /

The LoadModule lines might already exist. If so, make sure they are uncommented instead of adding them manually.

Then Tell Flask it is Behind a Proxy so that your application uses the X-Forwarded headers. X-Forwarded-For and X-Forwarded-Host are automatically set by ProxyPass.