added the ability to include only container having label using INCLUDE_LABEL param

README.md

@@ -51,9 +51,19 @@ Or, by adding a label which you define by setting an environment variable when r
         gliderlabs/logspout
     $ docker run -d --label logspout.exclude=true image
 
-#### Including specific containers
+#### Including explicit containers
 
-You can tell logspout to only include certain containers by setting filter parameters on the URI:
+You can tell logspout to include explicit containers by adding, for each container, a label which you define by setting an environment variable when running logspout:
+
+    $ docker run --name="logspout" \
+        -e INCLUDE_LABEL=logspout.include \
+        --volume=/var/run/docker.sock:/var/run/docker.sock \
+        gliderlabs/logspout
+    $ docker run -d --label logspout.include=true image
+
+#### Routing specific containers
+
+You can tell logspout to only route certain containers by setting filter parameters on the URI:
 
 	$ docker run \
 		--volume=/var/run/docker.sock:/var/run/docker.sock \

router/pump.go

@@ -73,6 +73,10 @@ func ignoreContainer(container *docker.Container) bool {
 	if value, ok := container.Config.Labels[excludeLabel]; ok {
 		return len(excludeLabel) > 0 && strings.ToLower(value) == "true"
 	}
+	includeLabel := getopt("INCLUDE_LABEL", "")
+    if _, ok := container.Config.Labels[includeLabel]; (includeLabel != "" && !ok) {
+            return true
+    }
 	return false
 }