Add support for unlinking component from service (#3651)

* Add support for unlinking component from service

* Changes based on PR feedback

pkg/envinfo/envinfo.go

@@ -327,6 +327,26 @@ func (esi *EnvSpecificInfo) DeleteURL(parameter string) error {
 	return esi.writeToFile()
 }
 
+func (esi *EnvSpecificInfo) DeleteLink(parameter string) error {
+	index := -1
+
+	for i, link := range *esi.componentSettings.Link {
+		if link.Name == parameter {
+			index = i
+			break
+		}
+	}
+
+	if index != -1 {
+		s := *esi.componentSettings.Link
+		s = append(s[:index], s[index+1:]...)
+		esi.componentSettings.Link = &s
+		return esi.writeToFile()
+	} else {
+		return nil
+	}
+}
+
 // GetComponentSettings returns the componentSettings from envinfo
 func (esi *EnvSpecificInfo) GetComponentSettings() ComponentSettings {
 	return esi.componentSettings

pkg/odo/cli/component/common_link.go

@@ -32,6 +32,8 @@ var (
 	sbrResource = "servicebindingrequests"
 )
 
+const unlink = "unlink"
+
 type commonLinkOptions struct {
 	wait             bool
 	port             string
@@ -74,22 +76,27 @@ func (o *commonLinkOptions) complete(name string, cmd *cobra.Command, args []str
 		}
 
 		if !sboSupport {
-			return fmt.Errorf("Please install Service Binding Operator to be able to create a link")
+			return fmt.Errorf("please install Service Binding Operator to be able to create/delete a link")
 		}
 
 		o.serviceType, o.serviceName, err = svc.IsOperatorServiceNameValid(suppliedName)
 		if err != nil {
 			return err
 		}
 
+		if o.operationName == unlink {
+			// rest of the code is specific to link operation
+			return nil
+		}
+
 		componentName := o.EnvSpecificInfo.GetName()
 
 		// Assign static/hardcoded values to SBR
 		o.sbr.Kind = sbrKind
 		o.sbr.APIVersion = strings.Join([]string{sbrGroup, sbrVersion}, "/")
 
 		// service binding request name will be like <component-name>-<service-type>-<service-name>. For example: nodejs-etcdcluster-example
-		o.sbr.Name = strings.Join([]string{componentName, strings.ToLower(o.serviceType), o.serviceName}, "-")
+		o.sbr.Name = getSBRName(componentName, o.serviceType, o.serviceName)
 		o.sbr.Namespace = o.EnvSpecificInfo.GetNamespace()
 		o.sbr.Spec.DetectBindingResources = true // because we want the operator what to bind from the service
 
@@ -172,6 +179,35 @@ func (o *commonLinkOptions) validate(wait bool) (err error) {
 			return fmt.Errorf("Couldn't find service named %q. Refer %q to see list of running services", svcFullName, "odo service list")
 		}
 
+		if o.operationName == unlink {
+			componentName := o.EnvSpecificInfo.GetName()
+			sbrName := getSBRName(componentName, o.serviceType, o.serviceName)
+			links := o.EnvSpecificInfo.GetLink()
+
+			linked := isComponentLinked(sbrName, links)
+			if !linked {
+				// user's trying to unlink a service that's not linked with the component
+				return fmt.Errorf("failed to unlink the service %q since it's not linked with the component %q", svcFullName, componentName)
+			}
+
+			// Verify if the underlying service binding request actually exists
+			sbrSvcFullName := strings.Join([]string{sbrKind, sbrName}, "/")
+			sbrExists, err := svc.OperatorSvcExists(o.KClient, sbrSvcFullName)
+			if err != nil {
+				return err
+			}
+			if !sbrExists {
+				// This could have happened if the service binding request was deleted outside odo workflow (eg: oc delete sbr/<sbr-name>)
+				// we must remove entry of the link from env.yaml in this case
+				err = o.Context.EnvSpecificInfo.DeleteLink(sbrName)
+				if err != nil {
+					return fmt.Errorf("component's link with %q has been deleted outside odo; unable to delete odo's state of the link", svcFullName)
+				}
+				return fmt.Errorf("component's link with %q has been deleted outside odo", svcFullName)
+			}
+			return nil
+		}
+
 		// since the service exists, let's get more info to populate service binding request
 		// first get the CR itself
 		cr, err := o.KClient.GetCustomResource(o.serviceType)
@@ -228,6 +264,24 @@ func (o *commonLinkOptions) validate(wait bool) (err error) {
 
 func (o *commonLinkOptions) run() (err error) {
 	if experimental.IsExperimentalModeEnabled() {
+		if o.operationName == unlink {
+			sbrName := getSBRName(o.EnvSpecificInfo.GetName(), o.serviceType, o.serviceName)
+			svcFullName := getSvcFullName(sbrKind, sbrName)
+			err = svc.DeleteServiceBindingRequest(o.KClient, svcFullName)
+			if err != nil {
+				return err
+			}
+
+			err = o.Context.EnvSpecificInfo.DeleteLink(sbrName)
+			if err != nil {
+				return err
+			}
+
+			log.Successf("Successfully unlinked component %q from service %q\n", o.Context.EnvSpecificInfo.GetName(), o.suppliedName)
+			log.Italic("To apply the changes, please use `odo push`")
+
+			return
+		}
 		// convert service binding request into a ma[string]interface{} type so
 		// as to use it with dynamic client
 		sbrMap := make(map[string]interface{})
@@ -242,7 +296,7 @@ func (o *commonLinkOptions) run() (err error) {
 		err = o.KClient.CreateDynamicResource(sbrMap, sbrGroup, sbrVersion, sbrResource)
 		if err != nil {
 			if strings.Contains(err.Error(), "already exists") {
-				return fmt.Errorf("Component %q is already linked with the service %q\n", o.Context.EnvSpecificInfo.GetName(), o.suppliedName)
+				return fmt.Errorf("component %q is already linked with the service %q\n", o.Context.EnvSpecificInfo.GetName(), o.suppliedName)
 			}
 			return err
 		}
@@ -343,3 +397,24 @@ func (o *commonLinkOptions) waitForLinkToComplete() (err error) {
 	_, err = o.Client.WaitAndGetPod(podSelector, corev1.PodRunning, "Waiting for component to start")
 	return err
 }
+
+// getSvcFullName returns service name in the format <service-type>/<service-name>
+func getSvcFullName(serviceType, serviceName string) string {
+	return strings.Join([]string{serviceType, serviceName}, "/")
+}
+
+// getSBRName creates a name to be used for creation/deletion of SBR during link/unlink operations
+func getSBRName(componentName, serviceType, serviceName string) string {
+	return strings.Join([]string{componentName, strings.ToLower(serviceType), serviceName}, "-")
+}
+
+// isComponentLinked checks if link with "sbrName" exists in the component's
+// config. It confirms if the component is linked with the service
+func isComponentLinked(sbrName string, links []envinfo.EnvInfoLink) bool {
+	for _, link := range links {
+		if link.Name == sbrName {
+			return true
+		}
+	}
+	return false
+}

pkg/service/service.go

@@ -141,6 +141,12 @@ func DeleteServiceAndUnlinkComponents(client *occlient.Client, serviceName strin
 	return nil
 }
 
+// DeleteServiceBindingRequest deletes a service binding request (when user
+// does odo unlink). It's just a wrapper on DeleteOperatorService
+func DeleteServiceBindingRequest(client *kclient.Client, serviceName string) error {
+	return DeleteOperatorService(client, serviceName)
+}
+
 // DeleteOperatorService deletes an Operator backed service
 // TODO: make it unlink the service from component as a part of
 // https://github.com/openshift/odo/issues/3563

tests/integration/operatorhub/cmd_service_test.go

@@ -407,7 +407,7 @@ spec:
 			Expect(stdOut).To(ContainSubstring("Couldn't find service named %q", "EtcdCluster/example"))
 		})
 
-		It("should successfully connect a component with an existing service", func() {
+		It("should successfully connect and disconnect a component with an existing service", func() {
 			if os.Getenv("KUBERNETES") == "true" {
 				Skip("This is a OpenShift specific scenario, skipping")
 			}
@@ -433,6 +433,22 @@ spec:
 
 			stdOut := helper.CmdShouldPass("odo", "link", "EtcdCluster/example")
 			Expect(stdOut).To(ContainSubstring("Successfully created link between component"))
+			stdOut = helper.CmdShouldFail("odo", "link", "EtcdCluster/example")
+			Expect(stdOut).To(ContainSubstring("already linked with the service"))
+
+			stdOut = helper.CmdShouldPass("odo", "unlink", "EtcdCluster/example")
+			Expect(stdOut).To(ContainSubstring("Successfully unlinked component"))
+
+			// verify that sbr is deleted
+			stdOut = helper.CmdShouldFail("odo", "unlink", "EtcdCluster/example")
+			Expect(stdOut).To(ContainSubstring("failed to unlink the service"))
+
+			// next, delete a link outside of odo (using oc) and ensure that it throws an error
+			helper.CmdShouldPass("odo", "link", "EtcdCluster/example")
+			sbrName := strings.Join([]string{componentName, "etcdcluster", "example"}, "-")
+			helper.CmdShouldPass("oc", "delete", fmt.Sprintf("ServiceBindingRequest/%s", sbrName))
+			stdOut = helper.CmdShouldFail("odo", "unlink", "EtcdCluster/example")
+			helper.MatchAllInOutput(stdOut, []string{"component's link with", "has been deleted outside odo"})
 		})
 	})
 })