Services are added as HostAliases to avoid naming collision

cncd/pipeline/pipec/exec_test.go

@@ -59,7 +59,7 @@ func TestKubeExec(t *testing.T) {
 	}
 
 	// os.Setenv("KUBECONFIG", "/etc/rancher/k3s/k3s.yaml")
-	engine, err := kubernetes.New("default", "local-storage", "100Mi")
+	engine, err := kubernetes.New("default", "example-nfs", "100Mi")
 	if err != nil {
 		t.Errorf("Could not start Kubernetes engine %f", err)
 	}

cncd/pipeline/pipeline/backend/kubernetes/kubernetes.go

@@ -66,30 +66,60 @@ func (e *engine) Setup(ctx context.Context, conf *backend.Config) error {
 		}
 	}
 
+	extraHosts := []string{}
+
+	for _, stage := range conf.Stages {
+		if stage.Alias == "services" {
+			for _, step := range stage.Steps {
+				e.logs.WriteString("Creating service\n")
+				pod := Pod(e.namespace, step)
+
+				var svc *v1.Service
+				for _, n := range step.Networks {
+					if len(n.Aliases) > 0 {
+						svc = Service(e.namespace, n.Aliases[0], pod.Name, step.Ports)
+					}
+				}
+
+				if _, err := e.kubeClient.CoreV1().Pods(e.namespace).Create(pod); err != nil {
+					return err
+				}
+				if svc, err := e.kubeClient.CoreV1().Services(e.namespace).Create(svc); err != nil {
+					return err
+				} else {
+					extraHosts = append(extraHosts, step.Networks[0].Aliases[0]+":"+svc.Spec.ClusterIP)
+				}
+			}
+		}
+	}
+
+	for _, stage := range conf.Stages {
+		if stage.Alias == "build" {
+			for _, step := range stage.Steps {
+				step.ExtraHosts = extraHosts
+			}
+		}
+	}
+
 	return nil
 }
 
 // Start the pipeline step.
 func (e *engine) Exec(ctx context.Context, step *backend.Step) error {
 	e.logs.WriteString("Creating pod\n")
-	pod, err := Pod(e.namespace, step)
-	if err != nil {
-		return err
-	}
+	pod := Pod(e.namespace, step)
 
+	var svc *v1.Service
 	for _, n := range step.Networks {
 		if len(n.Aliases) > 0 {
-			svc := Service(e.namespace, n.Aliases[0], pod.Name, step.Ports)
-			if svc == nil {
-				continue
-			}
-			if _, err := e.kubeClient.CoreV1().Services(e.namespace).Create(svc); err != nil {
-				return err
-			}
+			svc = Service(e.namespace, n.Aliases[0], pod.Name, step.Ports)
 		}
 	}
+	if svc != nil {
+		return nil // Pods with services are created already in Setup()
+	}
 
-	_, err = e.kubeClient.CoreV1().Pods(e.namespace).Create(pod)
+	_, err := e.kubeClient.CoreV1().Pods(e.namespace).Create(pod)
 	return err
 }
 

cncd/pipeline/pipeline/backend/kubernetes/pod.go

@@ -9,7 +9,7 @@ import (
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
 
-func Pod(namespace string, step *backend.Step) (*v1.Pod, error) {
+func Pod(namespace string, step *backend.Step) *v1.Pod {
 
 	var vols []v1.Volume
 	var volMounts []v1.VolumeMount
@@ -47,6 +47,12 @@ func Pod(namespace string, step *backend.Step) (*v1.Pod, error) {
 		args = []string{"echo $CI_SCRIPT | base64 -d | /bin/sh -e"}
 	}
 
+	hostAliases := []v1.HostAlias{}
+	for _, extraHost := range step.ExtraHosts {
+		host := strings.Split(extraHost, ":")
+		hostAliases = append(hostAliases, v1.HostAlias{IP: host[1], Hostnames: []string{host[0]}})
+	}
+
 	return &v1.Pod{
 		ObjectMeta: metav1.ObjectMeta{
 			Name:      podName(step),
@@ -57,6 +63,7 @@ func Pod(namespace string, step *backend.Step) (*v1.Pod, error) {
 		},
 		Spec: v1.PodSpec{
 			RestartPolicy: v1.RestartPolicyNever,
+			HostAliases:   hostAliases,
 			Containers: []v1.Container{{
 				Name:            podName(step),
 				Image:           step.Image,
@@ -70,7 +77,7 @@ func Pod(namespace string, step *backend.Step) (*v1.Pod, error) {
 			ImagePullSecrets: []v1.LocalObjectReference{{Name: "regcred"}},
 			Volumes:          vols,
 		},
-	}, nil
+	}
 }
 
 func podName(s *backend.Step) string {