Reverse proxy a site

Like Nginx, Fast-Https can reverse proxy server-side applications (PHP, Python, Java APIs or services) and works well as the front-end web server for a web application.

Reverse proxy architecture

Configure a reverse proxy on Windows

1 Start the upstream service

Start the application you want to proxy. Suppose you are deploying a Python Flask service — first make sure it runs correctly on this machine.

2 Edit the configuration file

Open fast-https.json in the config folder and configure the site:

The configuration file in the config folder

2.1 Minimal reverse proxy configuration

{
  "log_root": "./logs",
  "pid": "./fast-https.pid",
  "http": {
    "include": "mime.types",
    "server": [
      {
        "listen": 80,
        "server_name": "api.abc.com",
        "location": [
          {
            "url": "/",
            "type": "proxy",
            "proxy_pass": "http://127.0.0.1:5000",
            "proxy_set_header": [
              {
                "HeaderKey": "Host",
                "HeaderValue": "$host"
              },
              {
                "HeaderKey": "Connection",
                "HeaderValue": "close"
              }
            ]
          }
        ]
      }
    ]
  }
}

Option	Description
`listen`	Port the server listens on
`server_name`	Domain configured for this site
`url`	Request path that must be matched, or a regular expression; usually just `/`
`type`	`proxy` enables reverse proxying
`proxy_pass`	Upstream address and port to proxy to — a Python API, a PHP endpoint or a Java service; here a local Flask service
`proxy_set_header`	Replaces request headers while proxying; `HeaderKey` is the name, `HeaderValue` the value

2.2 About `proxy_set_header`

Values starting with $ are built-in variables replaced with real values; anything else is used literally. If the header did not exist, it is added.

$host — replaced with the server_name of the site in the configuration;
$proxy_host — replaced with the host name given in proxy_pass.

A common header configuration:

"proxy_set_header" : [
              {
                "HeaderKey": "Host",
                "HeaderValue": "$proxy_host"
              },
              {
                "HeaderKey": "Connection",
                "HeaderValue": "close"
              }
]

Which one to use depends on how the upstream validates the Host header.

3 WebSocket upstreams

If the upstream server exposes WebSocket endpoints, no extra option is needed in proxy_pass;
After configuring, ws://api.quwancode.com/XXXX reaches the matching WebSocket endpoint on the upstream server.

To speed up a reverse proxied site, add proxy_cache to the location — see "Cache a reverse proxy site".