Add support for virtual host redirection

README.md

@@ -52,7 +52,8 @@ services:
   whoami:
     image: jwilder/whoami
     environment:
-      - VIRTUAL_HOST=whoami.local
+      - VIRTUAL_HOST=whoami.local,www.whoami.local
+      - REDIRECT=www.whoami.local
 ```
 
 ```shell
@@ -82,6 +83,10 @@ If you need to support multiple virtual hosts for a container, you can separate
 
 You can also use wildcards at the beginning and the end of host name, like `*.bar.com` or `foo.bar.*`. Or even a regular expression, which can be very useful in conjunction with a wildcard DNS service like [xip.io](http://xip.io), using `~^foo\.bar\..*\.xip\.io` will match `foo.bar.127.0.0.1.xip.io`, `foo.bar.10.0.2.2.xip.io` and all other given IPs. More information about this topic can be found in the nginx documentation about [`server_names`](http://nginx.org/en/docs/http/server_names.html).
 
+### Redirect Hosts
+
+Using the `REDIRECT` environment variable, you can 301 permanent redirect all your virtual hosts to a specific host. Commonly used in production for SEO purposes. For example, you can redirect both `www.bar.com,bar.com` to `www.bar.com` using `REDIRECT=www.bar.com` or `www.bar.com,bar.com` to `bar.com` using `REDIRECT=bar.com`.
+
 ### Multiple Networks
 
 With the addition of [overlay networking](https://docs.docker.com/engine/userguide/networking/get-started-overlay/) in Docker 1.9, your `nginx-proxy` container may need to connect to backend containers on multiple networks. By default, if you don't pass the `--net` flag when your `nginx-proxy` container is created, it will only be attached to the default `bridge` network. This means that it will not be able to connect to containers on networks other than `bridge`.

nginx.tmpl

@@ -225,6 +225,8 @@ upstream {{ $upstream_name }} {
 {{/* Get the VIRTUAL_ROOT By containers w/ use fastcgi root */}}
 {{ $vhost_root := or (first (groupByKeys $containers "Env.VIRTUAL_ROOT")) "/var/www/public" }}
 
+{{/* Get the first redirect defined by containers w/ the same vhost */}}
+{{ $redirectHost := or (first (groupByKeys $containers "Env.REDIRECT")) ""}}
 
 {{/* Get the first cert name defined by containers w/ the same vhost */}}
 {{ $certName := (first (groupByKeys $containers "Env.CERT_NAME")) }}
@@ -260,10 +262,20 @@ server {
 		try_files $uri =404;
 		break;
 	}
-
+
+	{{ if (and $redirectHost (ne $redirectHost $host)) }}
+        # Redirect host {{ $host }} => {{ $redirectHost }}
+        {{ end }}
+
+	{{ if (and $redirectHost (ne $redirectHost $host)) }}
+	location / {
+                return 301 https://{{ $redirectHost }}$request_uri;
+        }
+	{{ else }}
 	location / {
 		return 301 https://$host$request_uri;
 	}
+	{{ end }}
 }
 {{ end }}
 
@@ -308,7 +320,12 @@ server {
 	{{ else if (exists "/etc/nginx/vhost.d/default") }}
 	include /etc/nginx/vhost.d/default;
 	{{ end }}
+
+	{{ if (and $redirectHost (ne $redirectHost $host)) }}
+        # Redirect host {{ $host }} => {{ $redirectHost }}
+        {{ end }}
 
+	{{ if (or (not $redirectHost) (eq $redirectHost $host)) }}
 	location / {
 		{{ if eq $proto "uwsgi" }}
 		include uwsgi_params;
@@ -333,6 +350,13 @@ server {
 		include /etc/nginx/vhost.d/default_location;
 		{{ end }}
 	}
+	{{ end }}
+
+	{{ if (and $redirectHost (ne $redirectHost $host)) }}
+        location / {
+                return 301 https://{{$redirectHost}}$request_uri;
+        }
+        {{ end }}
 }
 
 {{ end }}
@@ -357,7 +381,12 @@ server {
 	{{ else if (exists "/etc/nginx/vhost.d/default") }}
 	include /etc/nginx/vhost.d/default;
 	{{ end }}
+
+	{{ if (and $redirectHost (ne $redirectHost $host)) }}
+        # Redirect host {{ $host }} => {{ $redirectHost }}
+        {{ end }}
 
+	{{ if (or (not $redirectHost) (eq $redirectHost $host)) }}
 	location / {
 		{{ if eq $proto "uwsgi" }}
 		include uwsgi_params;
@@ -381,6 +410,13 @@ server {
 		include /etc/nginx/vhost.d/default_location;
 		{{ end }}
 	}
+	{{ end }}
+
+	{{ if (and $redirectHost (ne $redirectHost $host)) }}
+	location / {
+                return 301 http://{{ $redirectHost }}$request_uri;
+        }
+	{{ end }}	
 }
 
 {{ if (and (not $is_https) (exists "/etc/nginx/certs/default.crt") (exists "/etc/nginx/certs/default.key")) }}