Updated README.md, added info about integration with NGINX.

README.md

@@ -44,6 +44,9 @@
     - [PHP Application](#php-application)
     - [Python Application](#python-application)
     - [Full Example](#full-example)
+- [Integration with NGINX](#integration-with-nginx)
+  - [Installing Unit Behind NGINX](#installing-unit-behind-nginx)
+  - [Securing and Proxying Unit API](#securing-and-proxying-unit-api)
 - [Contribution](#contribution)
 - [Troubleshooting](#troubleshooting)
 
@@ -796,7 +799,118 @@ Example:
 
 <!-- /section:3 -->
 
-<!-- section:4 -->
+<!-- /section:4 -->
+
+## Integration with NGINX
+
+### Installing Unit Behind NGINX
+
+Configure NGINX as a static web server and reverse proxy in front of Unit.
+
+NGINX serves static files directly from the filesystem, and the requests to the
+applications are forwarded to Unit.
+
+Create an upstream block in `http` context of NGINX configuration:
+
+```
+upstream unit_backend {
+    
+}
+```
+
+Add Unit server IP and port to the upstream block, for example:
+
+```
+upstream unit_backend {
+    server 127.0.0.1:8300;
+}
+```
+
+Create or modify `server` and `location` blocks in `http` context of NGINX
+configuration. Specify static files directory and the name of Unit upstream.
+
+#### Example 1
+
+For PHP applications, all requests with URLs ending in `.php` will be proxied
+to Unit. All other files will be served directly by NGINX:
+
+
+```
+server {
+    location / {
+        root /var/www/static-data;
+    }
+    location ~ \.php$ {
+        proxy_pass http://unit_backend;
+        proxy_set_header Host $host;
+    }
+}
+```
+
+#### Example 2
+
+For the following application, all static files need to be placed in
+`/var/www/files` directory, and referenced by URLs starting with `/static`.
+All other requests will be proxied to Unit:
+
+```
+ server {
+
+    location /static {
+        root /var/www/files;
+    }
+
+    location / {
+        proxy_pass http://unit_backend;
+        proxy_set_header Host $host;
+    }
+}
+
+Refer to NGINX documentation at http://nginx.org/ for more information.
+Commercial support and advanced features are available at
+https://www.nginx.com/
+
+### Securing and Proxying Unit API
+
+By default, Unit API is available through a Unix domain socket. In order for
+the API to be available remotely, configure a reverse proxy with NGINX.
+
+NGINX can provide security, authentication, and access control to the API. It
+is not recommended to expose unsecure Unit API.
+
+Use the following configuration example for NGINX:
+
+```
+server {
+    
+    # Configure SSL encryption
+    server 443 ssl;
+    ssl_certificate /path/to/ssl/cert.pem;
+    ssl_certificate_key /path/to/ssl/cert.key;
+
+    # Configure SSL client certificate validation
+    ssl_client_certificate /path/to/ca.pem;
+    ssl_verify_client on;
+
+    # Configure network ACLs
+    #allow 1.2.3.4; # Uncomment and change to the IP addresses and networks
+                    # of the administrative systems.
+    deny all;
+
+    # Configure HTTP Basic authentication
+    auth_basic on;
+    auth_basic_user_file /path/to/htpasswd.txt;
+
+    location / {
+        proxy_pass http://unix:/path/to/control.unit.sock
+    }
+}
+
+```
+
+<!-- /section:4 -->
+
+<!-- section:5 -->
 
 ## Contribution
 
@@ -805,12 +919,12 @@ NGINX Unit is released under the Apache 2.0 license.
 To contribute changes, either submit them by email to <unit@nginx.org> or
 submit a pull request in the https://github.com/nginx/unit repository.
 
-<!-- /section:4 -->
+<!-- /section:5 -->
 
-<!-- section:5 -->
+<!-- section:6 -->
 
 ## Troubleshooting
 
 **TBD**
 
-<!-- /section:5 -->
+<!-- /section:6 -->