Add Gateway and HostPort to meta-data

Useful when running docker-gen within a container to generate
reverse proxy configs.

Author: jwilder

docker-gen.go

@@ -32,12 +32,14 @@ type Event struct {
 }
 
 type Address struct {
-	IP   string
-	Port string
+	IP       string
+	Port     string
+	HostPort string
 }
 type RuntimeContainer struct {
 	ID        string
 	Addresses []Address
+	Gateway   string
 	Image     DockerImage
 	Env       map[string]string
 }

docker_client.go

@@ -202,15 +202,21 @@ func getContainers(client *docker.Client) ([]*RuntimeContainer, error) {
 				Repository: repository,
 				Tag:        tag,
 			},
+			Gateway:   container.NetworkSettings.Gateway,
 			Addresses: []Address{},
 			Env:       make(map[string]string),
 		}
-		for k, _ := range container.NetworkSettings.Ports {
+		for k, v := range container.NetworkSettings.Ports {
+			address := Address{
+				IP:   container.NetworkSettings.IPAddress,
+				Port: k.Port(),
+			}
+			if len(v) > 0 {
+				address.HostPort = v[0].HostPort
+			}
 			runtimeContainer.Addresses = append(runtimeContainer.Addresses,
-				Address{
-					IP:   container.NetworkSettings.IPAddress,
-					Port: k.Port(),
-				})
+				address)
+
 		}
 
 		for _, entry := range container.Config.Env {