Update cli to check for metrics agent DaemonSet (#31)

The `v0.4.3` agent release modified `buoyant-cloud-metrics` to be a DaemonSet rather than a Deployment. The `linkerd-buoyant check` command was not updated to check for this. Modify `linkerd-buoyant check` to check for a DaemonSet instead. Also modify the check hint URL to point to `linkerd-buoyant`-specific documentation. Fixes #30 Signed-off-by: Andrew Seigner <[email protected]>
BuoyantIO · Sep 13, 2021 · 2082847 · 2082847
1 parent 95a0b60
commit 2082847
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Showing 4 changed files with 87 additions and 26 deletions.
diff --git a/cli/pkg/healthcheck/healthcheck.go b/cli/pkg/healthcheck/healthcheck.go
@@ -5,11 +5,11 @@ import (
 	"fmt"
 	"net/http"
 
+	agentk8s "github.com/buoyantio/linkerd-buoyant/agent/pkg/k8s"
 	"github.com/buoyantio/linkerd-buoyant/cli/pkg/k8s"
 	"github.com/buoyantio/linkerd-buoyant/cli/pkg/version"
 	"github.com/linkerd/linkerd2/pkg/healthcheck"
 	l5dk8s "github.com/linkerd/linkerd2/pkg/k8s"
-	appsv1 "k8s.io/api/apps/v1"
 	v1 "k8s.io/api/core/v1"
 )
 
@@ -31,6 +31,8 @@ type HealthChecker struct {
 	ns      *v1.Namespace
 }
 
+type getWorkloadLabelsFn func(ctx context.Context) (map[string]string, error)
+
 // NewHealthChecker returns an initialized HealthChecker for linkerd-buoyant.
 // The returned instance does not contain any linkerd-buoyant Categories.
 // Categories are to be explicitly added by using hc.AppendCategories
@@ -55,10 +57,10 @@ func (hc *HealthChecker) L5dBuoyantCategory() *healthcheck.Category {
 		hc.globalChecks(),
 		append(
 			hc.deploymentChecks(k8s.AgentName),
-			hc.deploymentChecks(k8s.MetricsName)...,
+			hc.daemonSetChecks(k8s.MetricsName)...,
 		)...,
 	)
-	return healthcheck.NewCategory(categoryID, checks, true)
+	return healthcheck.NewCategory(categoryID, checks, true).WithHintBaseURL("https://linkerd.io/checks#l5d-buoyant")
 }
 
 func (hc *HealthChecker) globalChecks() []healthcheck.Checker {
@@ -141,46 +143,86 @@ func (hc *HealthChecker) globalChecks() []healthcheck.Checker {
 }
 
 func (hc *HealthChecker) deploymentChecks(name string) []healthcheck.Checker {
-	var deploy *appsv1.Deployment
-	var pod v1.Pod
+	getWorkloadLabels := func(ctx context.Context) (map[string]string, error) {
+		deploy, err := hc.k8s.Deployment(ctx, name)
+		if err != nil {
+			return nil, err
+		}
+		return deploy.GetLabels(), nil
+	}
 
-	return []healthcheck.Checker{
-		*healthcheck.NewChecker(fmt.Sprintf("%s Deployment exists", name)).
+	return hc.workloadChecks(name, agentk8s.Deployment, getWorkloadLabels, true)
+}
+
+func (hc *HealthChecker) daemonSetChecks(name string) []healthcheck.Checker {
+	getWorkloadLabels := func(ctx context.Context) (map[string]string, error) {
+		ds, err := hc.k8s.DaemonSet(ctx, name)
+		if err != nil {
+			return nil, err
+		}
+		return ds.GetLabels(), nil
+	}
+
+	return hc.workloadChecks(name, agentk8s.DaemonSet, getWorkloadLabels, false)
+}
+
+func (hc *HealthChecker) workloadChecks(
+	name, kind string, getWorkloadLabels getWorkloadLabelsFn, singleton bool,
+) []healthcheck.Checker {
+	var labels map[string]string
+	var pods []v1.Pod
+
+	checks := []healthcheck.Checker{
+		*healthcheck.NewChecker(fmt.Sprintf("%s %s exists", name, kind)).
 			Fatal().
 			WithCheck(func(ctx context.Context) error {
 				var err error
-				deploy, err = hc.k8s.Deployment(ctx, name)
+				labels, err = getWorkloadLabels(ctx)
 				if err != nil {
 					return err
 				}
-				return checkLabel(deploy.GetLabels(), k8s.PartOfKey, k8s.PartOfVal)
+				return checkLabel(labels, k8s.PartOfKey, k8s.PartOfVal)
 			}),
-		*healthcheck.NewChecker(fmt.Sprintf("%s Deployment is running", name)).
+		*healthcheck.NewChecker(fmt.Sprintf("%s %s is running", name, kind)).
 			WithCheck(func(ctx context.Context) error {
 				labelSelector := fmt.Sprintf("app=%s", name)
-				pods, err := hc.k8s.Pods(ctx, labelSelector)
+				podList, err := hc.k8s.Pods(ctx, labelSelector)
 				if err != nil {
 					return err
 				}
 
-				if len(pods.Items) != 1 {
-					return fmt.Errorf("expected 1 %s pod, found %d", name, len(pods.Items))
-				}
+				pods = podList.Items
 
-				pod = pods.Items[0]
+				if len(pods) == 0 {
+					return fmt.Errorf("no running pods for %s %s", name, kind)
+				}
 
-				return healthcheck.CheckPodsRunning(pods.Items, "")
+				return healthcheck.CheckPodsRunning(pods, "")
 			}),
-		*healthcheck.NewChecker(fmt.Sprintf("%s Deployment is injected", name)).
+		*healthcheck.NewChecker(fmt.Sprintf("%s %s is injected", name, kind)).
 			WithCheck(func(ctx context.Context) error {
-				return healthcheck.CheckIfDataPlanePodsExist([]v1.Pod{pod})
+				return healthcheck.CheckIfDataPlanePodsExist(pods)
 			}),
-		*healthcheck.NewChecker(fmt.Sprintf("%s is up-to-date", name)).
+		*healthcheck.NewChecker(fmt.Sprintf("%s %s is up-to-date", name, kind)).
 			Warning().
 			WithCheck(func(ctx context.Context) error {
-				return checkLabel(deploy.GetLabels(), k8s.VersionLabel, hc.version)
+				return checkLabel(labels, k8s.VersionLabel, hc.version)
 			}),
 	}
+
+	if singleton {
+		checks = append(checks,
+			*healthcheck.NewChecker(fmt.Sprintf("%s %s is running a single pod", name, kind)).
+				WithCheck(func(ctx context.Context) error {
+					if len(pods) != 1 {
+						return fmt.Errorf("expected 1 %s pod, found %d", name, len(pods))
+					}
+					return nil
+				}),
+		)
+	}
+
+	return checks
 }
 
 func checkLabel(labels map[string]string, key, val string) error {

diff --git a/cli/pkg/healthcheck/healthcheck_test.go b/cli/pkg/healthcheck/healthcheck_test.go
@@ -75,7 +75,7 @@ func TestHealthChecker(t *testing.T) {
 √ buoyant-cloud Namespace exists
 × buoyant-cloud Namespace has correct labels
     missing linkerd.io/extension label
-    see https://linkerd.io/2/checks/# for hints
+    see https://linkerd.io/checks#l5d-buoyant for hints
 
 Status check results are ×
 `,
@@ -116,6 +116,9 @@ Status check results are ×
 						MockServiceAccount: &v1.ServiceAccount{
 							ObjectMeta: objMeta,
 						},
+						MockDaemonSet: &appsv1.DaemonSet{
+							ObjectMeta: objMetaDeploy,
+						},
 						MockDeployment: &appsv1.Deployment{
 							ObjectMeta: objMetaDeploy,
 						},
@@ -157,11 +160,12 @@ Status check results are ×
 √ buoyant-cloud-agent Deployment exists
 √ buoyant-cloud-agent Deployment is running
 √ buoyant-cloud-agent Deployment is injected
-√ buoyant-cloud-agent is up-to-date
-√ buoyant-cloud-metrics Deployment exists
-√ buoyant-cloud-metrics Deployment is running
-√ buoyant-cloud-metrics Deployment is injected
-√ buoyant-cloud-metrics is up-to-date
+√ buoyant-cloud-agent Deployment is up-to-date
+√ buoyant-cloud-agent Deployment is running a single pod
+√ buoyant-cloud-metrics DaemonSet exists
+√ buoyant-cloud-metrics DaemonSet is running
+√ buoyant-cloud-metrics DaemonSet is injected
+√ buoyant-cloud-metrics DaemonSet is up-to-date
 
 Status check results are √
 `,

diff --git a/cli/pkg/k8s/client.go b/cli/pkg/k8s/client.go
@@ -24,6 +24,8 @@ type (
 		Secret(ctx context.Context) (*v1.Secret, error)
 		// ServiceAccount retrieves the buoyant-cloud-agent ServiceAccount.
 		ServiceAccount(ctx context.Context) (*v1.ServiceAccount, error)
+		// DaemonSet retrieves a DaemonSet by name in the buoyant-cloud namespace.
+		DaemonSet(ctx context.Context, name string) (*appsv1.DaemonSet, error)
 		// Deployment retrieves a Deployment by name in the buoyant-cloud namespace.
 		Deployment(ctx context.Context, name string) (*appsv1.Deployment, error)
 		// Pods retrieves a PodList by labelSelector from the buoyant-cloud
@@ -107,6 +109,13 @@ func (c *client) ServiceAccount(ctx context.Context) (*v1.ServiceAccount, error)
 		Get(ctx, AgentName, metav1.GetOptions{})
 }
 
+func (c *client) DaemonSet(ctx context.Context, name string) (*appsv1.DaemonSet, error) {
+	return c.
+		AppsV1().
+		DaemonSets(Namespace).
+		Get(ctx, name, metav1.GetOptions{})
+}
+
 func (c *client) Deployment(ctx context.Context, name string) (*appsv1.Deployment, error) {
 	return c.
 		AppsV1().

diff --git a/cli/pkg/k8s/mock_client.go b/cli/pkg/k8s/mock_client.go
@@ -15,6 +15,7 @@ type MockClient struct {
 	MockClusterRoleBinding *rbacv1.ClusterRoleBinding
 	MockSecret             *v1.Secret
 	MockServiceAccount     *v1.ServiceAccount
+	MockDaemonSet          *appsv1.DaemonSet
 	MockDeployment         *appsv1.Deployment
 	MockPods               *v1.PodList
 
@@ -47,6 +48,11 @@ func (m *MockClient) ServiceAccount(ctx context.Context) (*v1.ServiceAccount, er
 	return m.MockServiceAccount, nil
 }
 
+// DaemonSet returns a mock DaemonSet object.
+func (m *MockClient) DaemonSet(ctx context.Context, name string) (*appsv1.DaemonSet, error) {
+	return m.MockDaemonSet, nil
+}
+
 // Deployment returns a mock Deployment object.
 func (m *MockClient) Deployment(ctx context.Context, name string) (*appsv1.Deployment, error) {
 	return m.MockDeployment, nil