Check config values before and after overriding (#13)

action/deregister.go

@@ -54,17 +54,21 @@ func DeregisterCLI(c *cli.Context) error {
 }
 
 // DeregisterK8s configures a VaaS client from K8s data and removes a backend
-func DeregisterK8s(podInfo *k8s.PodInfo, config CommonConfig) error {
+func DeregisterK8s(podInfo *k8s.PodInfo, config CommonConfig) (err error) {
 	config.Address = podInfo.GetPodIP()
 	config.Port = podInfo.GetDefaultPort()
-	director, err := podInfo.GetDirector()
+	config.Director, err = overrideValue(config.Director, podInfo.GetDirector(), "Director")
 	if err != nil {
-		return fmt.Errorf("could not find VaaS director in Pod info: %s", err)
+		return
+	}
+	config.VaaSURL, err = overrideValue(config.VaaSURL, podInfo.GetVaaSURL(), "VaaS URL")
+	if err != nil {
+		return
+	}
+	config.VaaSUser, err = overrideValue(config.VaaSUser, podInfo.GetVaaSUser(), "VaaS User")
+	if err != nil {
+		return
 	}
-	config.Director = director
-
-	config.VaaSURL = podInfo.GetVaaSURL()
-	config.VaaSUser = podInfo.GetVaaSUser()
 	err = config.GetSecretFromFile(config.VaaSKeyFile)
 	if err == nil {
 		return fmt.Errorf("error reading VaaS secret key: %s", err)
@@ -81,7 +85,7 @@ func DeregisterK8s(podInfo *k8s.PodInfo, config CommonConfig) error {
 		return fmt.Errorf("could not deregister: %s", err)
 	}
 
-	return errors.New("backend ID not provided")
+	return nil
 }
 
 // GetDeregisterFlags returns a list of flags available for this action

action/register.go

@@ -62,17 +62,23 @@ func RegisterCLI(c *cli.Context) error {
 }
 
 // RegisterK8s configures a VaaS client from K8s data and runs register()
-func RegisterK8s(podInfo *k8s.PodInfo, config CommonConfig) error {
+func RegisterK8s(podInfo *k8s.PodInfo, config CommonConfig) (err error) {
 	config.Address = podInfo.GetPodIP()
 	config.Port = podInfo.GetDefaultPort()
-	director, err := podInfo.GetDirector()
-	if err == nil {
-		config.Director = director
-	} else {
-		return fmt.Errorf("could not find VaaS director in Pod info: %s", err)
+
+	config.Director, err = overrideValue(config.Director, podInfo.GetDirector(), "Director")
+	if err != nil {
+		return
+	}
+	config.VaaSURL, err = overrideValue(config.VaaSURL, podInfo.GetVaaSURL(), "VaaS URL")
+	if err != nil {
+		return
 	}
-	config.VaaSURL = podInfo.GetVaaSURL()
-	config.VaaSUser = podInfo.GetVaaSUser()
+	config.VaaSUser, err = overrideValue(config.VaaSUser, podInfo.GetVaaSUser(), "VaaS User")
+	if err != nil {
+		return
+	}
+
 	err = config.GetSecretFromFile(config.VaaSKeyFile)
 	if err != nil {
 		return fmt.Errorf("error reading VaaS secret key: %s", err)
@@ -81,21 +87,34 @@ func RegisterK8s(podInfo *k8s.PodInfo, config CommonConfig) error {
 	apiClient := vaas.NewClient(config.VaaSURL, config.VaaSUser, config.VaaSKey)
 	weight, err := podInfo.GetWeight()
 	if err != nil {
-		log.Errorf("unusable weight found %q", weight)
+		log.Errorf("unusable weight %q found: %s", weight, err)
 		weight = 1
 	}
 
 	dcName := os.Getenv(EnvDC)
-	if dcName == "" {
-		dcName, err = podInfo.GetDataCenter()
-		if err != nil {
-			log.Errorf("unusable DC name found %q", dcName)
-		}
+	podDC, err := podInfo.GetDataCenter()
+	if err != nil {
+		log.Errorf("unusable DC name found %q: %s", dcName, err)
+	}
+	dcName, err = overrideValue(dcName, podDC, "DC")
+	if err != nil {
+		return
 	}
 
 	return register(apiClient, config, weight, dcName)
 }
 
+func overrideValue(oldValue, override, name string) (string, error) {
+	if override != "" {
+		log.Debugf("Overriding %s (%q) with %q form podInfo", name, oldValue, override)
+		return override, nil
+	}
+	if oldValue == "" {
+		return oldValue, fmt.Errorf("no value for %s", name)
+	}
+	return oldValue, nil
+}
+
 // register adds a backend to VaaS
 func register(client vaas.Client, cfg CommonConfig, weight int, dcName string) (err error) {
 	var tags []string
@@ -109,6 +128,9 @@ func register(client vaas.Client, cfg CommonConfig, weight int, dcName string) (
 	}
 
 	director, err := client.FindDirector(cfg.Director)
+	if err != nil {
+		return fmt.Errorf("failed finding Director: %s", err)
+	}
 
 	backend := vaas.Backend{
 		ID:                 nil,

action/register_test.go

@@ -0,0 +1,35 @@
+package action
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestIfOverrides(t *testing.T) {
+	value := "value1"
+
+	result, err := overrideValue(value, "value2", "value")
+
+	require.NoError(t, err)
+	require.Equal(t, "value2", result)
+}
+
+func TestIfDoesNotOverrideOnEmpty(t *testing.T) {
+	value := "value1"
+
+	result, err := overrideValue(value, "", "value")
+
+	require.NoError(t, err)
+	require.Equal(t, "value1", result)
+}
+
+func TestIfOverrideErrorsOnEmpty(t *testing.T) {
+	value := ""
+
+	result, err := overrideValue(value, "", "value")
+
+	require.Error(t, err)
+	require.Equal(t, "no value for value", err.Error())
+	require.Equal(t, "", result)
+}

k8s/client_test.go

@@ -77,8 +77,7 @@ func TestIfReturnsCorrectAnnotationData(t *testing.T) {
 	podInfo, err := GetPodInfo()
 	require.NoError(t, err)
 
-	actualDirector, _ := podInfo.GetDirector()
-	require.Equal(t, expectedVipName, actualDirector)
+	require.Equal(t, expectedVipName, podInfo.GetDirector())
 
 	actualDC, _ := podInfo.GetDataCenter()
 	require.Equal(t, expectedDC, actualDC)
@@ -104,8 +103,7 @@ func TestIfReturnsErroredAnnotationData(t *testing.T) {
 	podInfo, err := GetPodInfo()
 	require.NoError(t, err)
 
-	_, err = podInfo.GetDirector()
-	require.EqualError(t, err, fmt.Sprintf("director annotation is empty, annotation key: %s", keyDirector))
+	require.Equal(t, "", podInfo.GetDirector())
 
 	_, err = podInfo.GetDataCenter()
 	require.EqualError(t, err, fmt.Sprintf("dc annotation is empty, annotation key: %s", keyDC))

k8s/pod.go

@@ -97,14 +97,12 @@ func (pi PodInfo) GetEnvironment() (string, error) {
 
 // GetVaaSURL returns VaaS URL
 func (pi PodInfo) GetVaaSURL() string {
-	url := pi.FindAnnotation(keyVaaSURL)
-	return url
+	return pi.FindAnnotation(keyVaaSURL)
 }
 
 // GetVaaSUser returns VaaS API Username
 func (pi PodInfo) GetVaaSUser() string {
-	username := pi.FindAnnotation(keyVaaSUser)
-	return username
+	return pi.FindAnnotation(keyVaaSUser)
 }
 
 // GetPodIP returns a Pod IP address
@@ -113,12 +111,8 @@ func (pi PodInfo) GetPodIP() string {
 }
 
 // GetDirector looks up VaaS director name in Pod annotations
-func (pi PodInfo) GetDirector() (string, error) {
-	director := pi.FindAnnotation(keyDirector)
-	if director == "" {
-		return "", fmt.Errorf("director annotation is empty, annotation key: %s", keyDirector)
-	}
-	return director, nil
+func (pi PodInfo) GetDirector() string {
+	return pi.FindAnnotation(keyDirector)
 }
 
 // GetPodInfo fetches k8s PodInfo for the current Pod