[POA-3003] Handle deployment tags for daemonSet's apidump processes (#86)

Changes in this PR:

* Changes in the deployment package's functions to accept the envVars
map as the input
* Use these functions while creating podArgs object in the kube run
command
* Add check in the apidump process to not call deployment.UpdateTags()
function again if the process is started by the parent `kube run`
command

**Note:** Here, for `hostname`, we expect the `HOSTNAME` environment
variable to be set, but it is required. It is set for our pods in
Postman, but it is not set in a pod running in Minikube locally.

Author: mudit-postman

apidump/apidump.go

@@ -77,6 +77,7 @@ type DaemonsetArgs struct {
 	StopChan                  <-chan error `json:"-"`
 	APIKey                    string
 	Environment               string
+	TraceTags                 tags.SingletonTags
 }
 
 type Args struct {
@@ -374,19 +375,27 @@ func collectTraceTags(args *Args) map[tags.Key]string {
 	// Set legacy deployment tags.
 	traceTags[tags.XAkitaDeployment] = apispec.DefaultDeployment
 	traceTags[tags.XAkitaSource] = tags.DeploymentSource
-	deployment.UpdateTags(traceTags)
+
+	// Set tags from the daemonSet apidump process
+	// Here we expect that the parent go routine has already set the tags
+	// if DaemonsetArgs is set.
+	if dArgs, exists := args.DaemonsetArgs.Get(); exists {
+		for k, v := range dArgs.TraceTags {
+			traceTags[k] = v
+		}
+	} else {
+		deployment.UpdateTags(traceTags)
+		hostname, err := os.Hostname()
+		if err == nil {
+			traceTags[tags.XInsightsHostname] = hostname
+		}
+	}
 
 	// Set source to user by default (if not CI or deployment)
 	if _, ok := traceTags[tags.XAkitaSource]; !ok {
 		traceTags[tags.XAkitaSource] = tags.UserSource
 	}
 
-	// Set hostname tag
-	hostname, err := os.Hostname()
-	if err == nil {
-		traceTags[tags.XInsightsHostname] = hostname
-	}
-
 	printer.Debugln("trace tags:", traceTags)
 	return traceTags
 }

cmd/internal/kube/daemonset/apidump_process.go

@@ -87,6 +87,7 @@ func (d *Daemonset) StartApiDumpProcess(podUID types.UID) error {
 				StopChan:                  podArgs.StopChan,
 				APIKey:                    podArgs.PodCreds.InsightsAPIKey,
 				Environment:               podArgs.PodCreds.InsightsEnvironment,
+				TraceTags:                 podArgs.TraceTags,
 			}),
 		}
 

cmd/internal/kube/daemonset/kube_events_worker.go

@@ -3,6 +3,7 @@ package daemonset
 import (
 	"github.com/akitasoftware/akita-libs/akid"
 	"github.com/pkg/errors"
+	"github.com/postmanlabs/postman-insights-agent/deployment"
 	"github.com/postmanlabs/postman-insights-agent/printer"
 	coreV1 "k8s.io/api/core/v1"
 )
@@ -179,6 +180,9 @@ func (d *Daemonset) inspectPodForEnvVars(pod coreV1.Pod, podArgs *PodArgs) error
 		return requiredEnvVarMissingErr
 	}
 
+	// Set the trace tags for apidump process from the pod info
+	deployment.SetK8sTraceTags(pod, podArgs.TraceTags)
+
 	podArgs.ContainerUUID = containerUUID
 	podArgs.InsightsProjectID = insightsProjectID
 	podArgs.PodCreds = PodCreds{

cmd/internal/kube/daemonset/pod_args.go

@@ -6,6 +6,7 @@ import (
 	"sync"
 
 	"github.com/akitasoftware/akita-libs/akid"
+	"github.com/akitasoftware/akita-libs/tags"
 	"github.com/pkg/errors"
 )
 
@@ -40,6 +41,7 @@ type PodCreds struct {
 type PodArgs struct {
 	// apidump related fields
 	InsightsProjectID akid.ServiceID
+	TraceTags         tags.SingletonTags
 
 	// Pod related fields
 	PodName       string
@@ -48,15 +50,16 @@ type PodArgs struct {
 
 	// for state management
 	PodTrafficMonitorState PodTrafficMonitorState
-	StateChangeMutex       sync.Mutex
+	StateChangeMutex       sync.Mutex `json:"-"`
 
 	// send stop signal to apidump process
-	StopChan chan error
+	StopChan chan error `json:"-"`
 }
 
 func NewPodArgs(podName string) *PodArgs {
 	return &PodArgs{
-		PodName: podName,
+		TraceTags: tags.SingletonTags{},
+		PodName:   podName,
 		// though 1 buffer size is enough, keeping 2 for safety
 		StopChan: make(chan error, 2),
 	}

deployment/deployment.go

@@ -5,6 +5,7 @@ import (
 
 	"github.com/akitasoftware/akita-libs/tags"
 	"github.com/postmanlabs/postman-insights-agent/printer"
+	coreV1 "k8s.io/api/core/v1"
 )
 
 // Internal type of the deployment, automatically discovered.
@@ -106,3 +107,14 @@ func UpdateTags(argsTags map[tags.Key]string) {
 		argsTags[k] = v
 	}
 }
+
+// SetK8sTraceTags sets Kubernetes-specific tags in the trace tags.
+// This is used by daemonset to set tags for traces from a specific pod.
+func SetK8sTraceTags(pod coreV1.Pod, traceTags tags.SingletonTags) {
+	traceTags[tags.XAkitaKubernetesNamespace] = pod.Namespace
+	traceTags[tags.XAkitaKubernetesNode] = pod.Spec.NodeName
+	traceTags[tags.XAkitaKubernetesPod] = pod.Name
+	traceTags[tags.XAkitaKubernetesPodIP] = pod.Status.PodIP
+	traceTags[tags.XAkitaKubernetesHostIP] = pod.Status.HostIP
+	traceTags[tags.XInsightsHostname] = pod.Name
+}