cleaner way to isolate

chaos/chaos_test.go

@@ -132,12 +132,7 @@ func TestIsolateOneInstance(t *testing.T) {
 	}()
 
 	// now go ahead and isolate for 30s
-	isolate("metrictank4", "30s", "metrictank0", "metrictank1", "metrictank2", "metrictank3", "metrictank5")
-	isolate("metrictank0", "30s", "metrictank4")
-	isolate("metrictank1", "30s", "metrictank4")
-	isolate("metrictank2", "30s", "metrictank4")
-	isolate("metrictank3", "30s", "metrictank4")
-	isolate("metrictank5", "30s", "metrictank4")
+	isolate([]string{"metrictank4"}, []string{"metrictank0", "metrictank1", "metrictank2", "metrictank3", "metrictank5"}, "30s")
 
 	// collect results of the minute long experiment
 	mt4Results := <-mt4ResultsChan

chaos/docker.go

@@ -59,8 +59,27 @@ func stop(name string) error {
 	return cmd.Run()
 }
 
-// isolate isolates traffic from the given docker container to all others matching the expression
-func isolate(name, dur string, targets ...string) error {
+// isolate isolates traffic between containers in setA and containers in setB
+func isolate(setA, setB []string, dur string) error {
+	// note: isolateOut should return very fast (order of ms)
+	// so we can run all this in serial
+	for _, a := range setA {
+		err := isolateOut(a, dur, setB...)
+		if err != nil {
+			return err
+		}
+	}
+	for _, b := range setB {
+		err := isolateOut(b, dur, setA...)
+		if err != nil {
+			return err
+		}
+	}
+	return nil
+}
+
+// isolateOut isolates traffic from the given docker container to all others matching the expression
+func isolateOut(name, dur string, targets ...string) error {
 	containers, err := cli.ContainerList(context.Background(), types.ContainerListOptions{})
 	if err != nil {
 		return err