Engine: integer job status, improved stream API

* Jobs return an integer status instead of a string
* Status convention mimics unix process execution: 0=success, 1=generic error, 127="no such command"
* Stdout and Stderr support multiple thread-safe data receivers and ring buffer filtering

integration/api_test.go

@@ -304,6 +304,10 @@ func TestGetContainersJSON(t *testing.T) {
 		Cmd:   []string{"echo", "test"},
 	}, t)
 
+	if containerID == "" {
+		t.Fatalf("Received empty container ID")
+	}
+
 	req, err := http.NewRequest("GET", "/containers/json?all=1", nil)
 	if err != nil {
 		t.Fatal(err)

integration/container_test.go

@@ -499,7 +499,7 @@ func TestCreateVolume(t *testing.T) {
 		t.Fatal(err)
 	}
 	var id string
-	jobCreate.StdoutParseString(&id)
+	jobCreate.Stdout.AddString(&id)
 	if err := jobCreate.Run(); err != nil {
 		t.Fatal(err)
 	}
@@ -1502,7 +1502,7 @@ func TestOnlyLoopbackExistsWhenUsingDisableNetworkOption(t *testing.T) {
 		t.Fatal(err)
 	}
 	var id string
-	jobCreate.StdoutParseString(&id)
+	jobCreate.Stdout.AddString(&id)
 	if err := jobCreate.Run(); err != nil {
 		t.Fatal(err)
 	}

integration/runtime_test.go

@@ -390,7 +390,7 @@ func startEchoServerContainer(t *testing.T, proto string) (*docker.Runtime, *doc
 		jobCreate.SetenvList("Cmd", []string{"sh", "-c", cmd})
 		jobCreate.SetenvList("PortSpecs", []string{fmt.Sprintf("%s/%s", strPort, proto)})
 		jobCreate.SetenvJson("ExposedPorts", ep)
-		jobCreate.StdoutParseString(&id)
+		jobCreate.Stdout.AddString(&id)
 		if err := jobCreate.Run(); err != nil {
 			t.Fatal(err)
 		}

integration/server_test.go

@@ -224,7 +224,7 @@ func TestRunWithTooLowMemoryLimit(t *testing.T) {
 	job.Setenv("CpuShares", "1000")
 	job.SetenvList("Cmd", []string{"/bin/cat"})
 	var id string
-	job.StdoutParseString(&id)
+	job.Stdout.AddString(&id)
 	if err := job.Run(); err == nil {
 		t.Errorf("Memory limit is smaller than the allowed limit. Container creation should've failed!")
 	}

integration/utils_test.go

@@ -46,7 +46,7 @@ func createNamedTestContainer(eng *engine.Engine, config *docker.Config, f utils
 	if err := job.ImportEnv(config); err != nil {
 		f.Fatal(err)
 	}
-	job.StdoutParseString(&shortId)
+	job.Stdout.AddString(&shortId)
 	if err := job.Run(); err != nil {
 		f.Fatal(err)
 	}