Cascade two else blocks into one using coalesce on VIRTUAL_PORT and 80

This also takes care of the case when VIRTUAL_PORT is not actually
exposed.

nginx.tmpl

@@ -54,29 +54,17 @@ upstream {{ $host }} {
 			# {{$container.Name}}
 			server {{ $address.IP }}:{{ $address.Port }};
 		{{ end }}
-	{{/* If more than one port exposed, use the one matching VIRTUAL_PORT env var */}}
-	{{ else if $container.Env.VIRTUAL_PORT }}
-		{{ range $address := .Addresses }}
-		   {{ if eq $address.Port $container.Env.VIRTUAL_PORT }}
-			{{ if and $container.Node $address.HostPort }}
-				# {{ $container.Node.Name }}/{{$container.Name}}
-				server {{ $container.Node.Address.IP }}:{{ $address.HostPort }};
-			{{ else }}
-				# {{$container.Name}}
-				server {{ $address.IP }}:{{ $address.Port }};
-			{{ end }}
-		   {{ end }}
-		{{ end }}
-	{{/* Else default to standard web port 80 */}}
+	{{/* If more than one port exposed, use the one matching VIRTUAL_PORT env var, falling back to standard web port 80 */}}
 	{{ else }}
-		{{ $address := where $container.Addresses "Port" "80" | first }}
+		{{ $port := coalesce $container.Env.VIRTUAL_PORT "80" }}
+		{{ $address := where $container.Addresses "Port" $port | first }}
 		{{ if $address }}
 			{{ if and $container.Node $address.HostPort }}
 				# {{ $container.Node.Name }}/{{$container.Name}}
 				server {{ $container.Node.Address.IP }}:{{ $address.HostPort }};
 			{{ else }}
 				# {{$container.Name}}
-				server {{ $address.IP }}:80;
+				server {{ $address.IP }}:{{ $address.Port }};
 			{{ end }}
 		{{ else }}
 			# {{$container.Name}}