feat: Implement agent heartbeat with mTLS and node status tracking

cmd/kat-agent/main.go

@@ -265,6 +265,10 @@ func runInit(cmd *cobra.Command, args []string) {
 				joinHandler := api.NewJoinHandler(etcdStore, caKeyPath, caCertPath)
 				apiServer.RegisterJoinHandler(joinHandler)
 				log.Printf("Registered join handler with CA key: %s, CA cert: %s", caKeyPath, caCertPath)
+		
+				// Register the node status handler
+				nodeStatusHandler := api.NewNodeStatusHandler(etcdStore)
+				apiServer.RegisterNodeStatusHandler(nodeStatusHandler)
 
 				// Start the server in a goroutine
 				go func() {
@@ -333,7 +337,8 @@ func runJoin(cmd *cobra.Command, args []string) {
 	pkiDir := filepath.Join(os.Getenv("HOME"), ".kat-agent", nodeName, "pki")
 
 	// Join the cluster
-	if err := cli.JoinCluster(leaderAPI, advertiseAddr, nodeName, leaderCACert, pkiDir); err != nil {
+	joinResp, err := cli.JoinCluster(leaderAPI, advertiseAddr, nodeName, leaderCACert, pkiDir)
+	if err != nil {
 		log.Fatalf("Failed to join cluster: %v", err)
 	}
 
@@ -343,20 +348,36 @@ func runJoin(cmd *cobra.Command, args []string) {
 	ctx, stop := signal.NotifyContext(context.Background(), syscall.SIGINT, syscall.SIGTERM)
 	defer stop()
 	
-	// Stay up in an idle loop until interrupted
+	// Create and start the agent with heartbeating
-	log.Printf("Node %s is now running. Press Ctrl+C to exit.", nodeName)
+	agent, err := agent.NewAgent(
-	ticker := time.NewTicker(30 * time.Second)
+		joinResp.NodeName,
-	defer ticker.Stop()
+		joinResp.NodeUID,
-	
+		leaderAPI,
-	for {
+		advertiseAddr,
-		select {
+		pkiDir,
-		case <-ctx.Done():
+		15, // Default heartbeat interval in seconds
-			log.Println("Received shutdown signal. Exiting...")
+	)
-			return
+	if err != nil {
-		case <-ticker.C:
+		log.Fatalf("Failed to create agent: %v", err)
-			log.Printf("Node %s is still running...", nodeName)
-		}
 	}
+	
+	// Setup mTLS client
+	if err := agent.SetupMTLSClient(); err != nil {
+		log.Fatalf("Failed to setup mTLS client: %v", err)
+	}
+	
+	// Start heartbeating
+	if err := agent.StartHeartbeat(ctx); err != nil {
+		log.Fatalf("Failed to start heartbeat: %v", err)
+	}
+	
+	log.Printf("Node %s is now running with heartbeat. Press Ctrl+C to exit.", nodeName)
+	
+	// Wait for shutdown signal
+	<-ctx.Done()
+	log.Println("Received shutdown signal. Stopping heartbeat...")
+	agent.StopHeartbeat()
+	log.Println("Exiting...")
 }
 
 func runVerify(cmd *cobra.Command, args []string) {

internal/agent/agent.go

@@ -0,0 +1,248 @@
+package agent
+
+import (
+	"bytes"
+	"context"
+	"crypto/tls"
+	"crypto/x509"
+	"encoding/json"
+	"fmt"
+	"log"
+	"net/http"
+	"os"
+	"runtime"
+	"time"
+)
+
+// NodeStatus represents the data sent in a heartbeat
+type NodeStatus struct {
+	NodeName    string    `json:"nodeName"`
+	NodeUID     string    `json:"nodeUID"`
+	Timestamp   time.Time `json:"timestamp"`
+	Resources   Resources `json:"resources"`
+	Workloads   []WorkloadStatus `json:"workloadInstances,omitempty"`
+	NetworkInfo NetworkInfo `json:"overlayNetwork"`
+}
+
+// Resources represents the node's resource capacity and usage
+type Resources struct {
+	Capacity    ResourceMetrics `json:"capacity"`
+	Allocatable ResourceMetrics `json:"allocatable"`
+}
+
+// ResourceMetrics contains CPU and memory metrics
+type ResourceMetrics struct {
+	CPU    string `json:"cpu"`    // e.g., "2000m"
+	Memory string `json:"memory"` // e.g., "4096Mi"
+}
+
+// WorkloadStatus represents the status of a workload instance
+type WorkloadStatus struct {
+	WorkloadName  string `json:"workloadName"`
+	Namespace     string `json:"namespace"`
+	InstanceID    string `json:"instanceID"`
+	ContainerID   string `json:"containerID"`
+	ImageID       string `json:"imageID"`
+	State         string `json:"state"`         // "running", "exited", "paused", "unknown"
+	ExitCode      int    `json:"exitCode"`
+	HealthStatus  string `json:"healthStatus"`  // "healthy", "unhealthy", "pending_check"
+	Restarts      int    `json:"restarts"`
+}
+
+// NetworkInfo contains information about the node's overlay network
+type NetworkInfo struct {
+	Status       string `json:"status"`       // "connected", "disconnected", "initializing"
+	LastPeerSync string `json:"lastPeerSync"` // timestamp
+}
+
+// Agent represents a KAT agent node
+type Agent struct {
+	NodeName      string
+	NodeUID       string
+	LeaderAPI     string
+	AdvertiseAddr string
+	PKIDir        string
+	
+	// mTLS client for leader communication
+	client        *http.Client
+	
+	// Heartbeat configuration
+	heartbeatInterval time.Duration
+	stopHeartbeat     chan struct{}
+}
+
+// NewAgent creates a new Agent instance
+func NewAgent(nodeName, nodeUID, leaderAPI, advertiseAddr, pkiDir string, heartbeatIntervalSeconds int) (*Agent, error) {
+	if heartbeatIntervalSeconds <= 0 {
+		heartbeatIntervalSeconds = 15 // Default to 15 seconds
+	}
+	
+	return &Agent{
+		NodeName:          nodeName,
+		NodeUID:           nodeUID,
+		LeaderAPI:         leaderAPI,
+		AdvertiseAddr:     advertiseAddr,
+		PKIDir:            pkiDir,
+		heartbeatInterval: time.Duration(heartbeatIntervalSeconds) * time.Second,
+		stopHeartbeat:     make(chan struct{}),
+	}, nil
+}
+
+// SetupMTLSClient configures the HTTP client with mTLS using the agent's certificates
+func (a *Agent) SetupMTLSClient() error {
+	// Load client certificate and key
+	cert, err := tls.LoadX509KeyPair(
+		fmt.Sprintf("%s/node.crt", a.PKIDir),
+		fmt.Sprintf("%s/node.key", a.PKIDir),
+	)
+	if err != nil {
+		return fmt.Errorf("failed to load client certificate and key: %w", err)
+	}
+
+	// Load CA certificate
+	caCert, err := os.ReadFile(fmt.Sprintf("%s/ca.crt", a.PKIDir))
+	if err != nil {
+		return fmt.Errorf("failed to read CA certificate: %w", err)
+	}
+
+	caCertPool := x509.NewCertPool()
+	if !caCertPool.AppendCertsFromPEM(caCert) {
+		return fmt.Errorf("failed to append CA certificate to pool")
+	}
+
+	// Create TLS configuration
+	tlsConfig := &tls.Config{
+		Certificates: []tls.Certificate{cert},
+		RootCAs:      caCertPool,
+		MinVersion:   tls.VersionTLS12,
+	}
+
+	// Create HTTP client with TLS configuration
+	a.client = &http.Client{
+		Transport: &http.Transport{
+			TLSClientConfig: tlsConfig,
+		},
+		Timeout: 10 * time.Second,
+	}
+
+	return nil
+}
+
+// StartHeartbeat begins sending periodic heartbeats to the leader
+func (a *Agent) StartHeartbeat(ctx context.Context) error {
+	if a.client == nil {
+		if err := a.SetupMTLSClient(); err != nil {
+			return fmt.Errorf("failed to setup mTLS client: %w", err)
+		}
+	}
+
+	log.Printf("Starting heartbeat to leader at %s every %v", a.LeaderAPI, a.heartbeatInterval)
+
+	ticker := time.NewTicker(a.heartbeatInterval)
+	defer ticker.Stop()
+
+	// Send initial heartbeat immediately
+	if err := a.sendHeartbeat(); err != nil {
+		log.Printf("Initial heartbeat failed: %v", err)
+	}
+
+	go func() {
+		for {
+			select {
+			case <-ticker.C:
+				if err := a.sendHeartbeat(); err != nil {
+					log.Printf("Heartbeat failed: %v", err)
+				}
+			case <-a.stopHeartbeat:
+				log.Printf("Heartbeat stopped")
+				return
+			case <-ctx.Done():
+				log.Printf("Heartbeat context cancelled")
+				return
+			}
+		}
+	}()
+
+	return nil
+}
+
+// StopHeartbeat stops the heartbeat goroutine
+func (a *Agent) StopHeartbeat() {
+	close(a.stopHeartbeat)
+}
+
+// sendHeartbeat sends a single heartbeat to the leader
+func (a *Agent) sendHeartbeat() error {
+	// Gather node status
+	status := a.gatherNodeStatus()
+
+	// Marshal to JSON
+	statusJSON, err := json.Marshal(status)
+	if err != nil {
+		return fmt.Errorf("failed to marshal node status: %w", err)
+	}
+
+	// Construct URL
+	url := fmt.Sprintf("https://%s/v1alpha1/nodes/%s/status", a.LeaderAPI, a.NodeName)
+
+	// Create request
+	req, err := http.NewRequest("POST", url, bytes.NewBuffer(statusJSON))
+	if err != nil {
+		return fmt.Errorf("failed to create request: %w", err)
+	}
+	req.Header.Set("Content-Type", "application/json")
+
+	// Send request
+	resp, err := a.client.Do(req)
+	if err != nil {
+		return fmt.Errorf("failed to send heartbeat: %w", err)
+	}
+	defer resp.Body.Close()
+
+	// Check response
+	if resp.StatusCode != http.StatusOK {
+		return fmt.Errorf("heartbeat returned non-OK status: %d", resp.StatusCode)
+	}
+
+	log.Printf("Heartbeat sent successfully to %s", url)
+	return nil
+}
+
+// gatherNodeStatus collects the current node status
+func (a *Agent) gatherNodeStatus() NodeStatus {
+	// For now, just provide basic information
+	// In future phases, this will include actual resource usage, workload status, etc.
+	
+	// Get basic system info for initial capacity reporting
+	var m runtime.MemStats
+	runtime.ReadMemStats(&m)
+	
+	// Convert to human-readable format (very simplified for now)
+	cpuCapacity := fmt.Sprintf("%dm", runtime.NumCPU() * 1000)
+	memCapacity := fmt.Sprintf("%dMi", m.Sys / (1024 * 1024))
+	
+	// For allocatable, we'll just use 90% of capacity for this phase
+	cpuAllocatable := fmt.Sprintf("%dm", runtime.NumCPU() * 900)
+	memAllocatable := fmt.Sprintf("%dMi", (m.Sys / (1024 * 1024)) * 9 / 10)
+	
+	return NodeStatus{
+		NodeName:  a.NodeName,
+		NodeUID:   a.NodeUID,
+		Timestamp: time.Now(),
+		Resources: Resources{
+			Capacity: ResourceMetrics{
+				CPU:    cpuCapacity,
+				Memory: memCapacity,
+			},
+			Allocatable: ResourceMetrics{
+				CPU:    cpuAllocatable,
+				Memory: memAllocatable,
+			},
+		},
+		NetworkInfo: NetworkInfo{
+			Status:       "initializing", // Placeholder until network is implemented
+			LastPeerSync: time.Now().Format(time.RFC3339),
+		},
+		// Workloads will be empty for now
+	}
+}

internal/agent/agent_test.go

@@ -0,0 +1,137 @@
+package agent
+
+import (
+	"context"
+	"crypto/tls"
+	"crypto/x509"
+	"encoding/json"
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"os"
+	"path/filepath"
+	"testing"
+	"time"
+
+	"git.dws.rip/dubey/kat/internal/pki"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestAgentHeartbeat(t *testing.T) {
+	// Create temporary directory for test PKI files
+	tempDir, err := os.MkdirTemp("", "kat-test-agent-*")
+	if err != nil {
+		t.Fatalf("Failed to create temp directory: %v", err)
+	}
+	defer os.RemoveAll(tempDir)
+
+	// Generate CA for testing
+	pkiDir := filepath.Join(tempDir, "pki")
+	caKeyPath := filepath.Join(pkiDir, "ca.key")
+	caCertPath := filepath.Join(pkiDir, "ca.crt")
+	err = pki.GenerateCA(pkiDir, caKeyPath, caCertPath)
+	if err != nil {
+		t.Fatalf("Failed to generate test CA: %v", err)
+	}
+
+	// Generate node certificate
+	nodeKeyPath := filepath.Join(pkiDir, "node.key")
+	nodeCSRPath := filepath.Join(pkiDir, "node.csr")
+	nodeCertPath := filepath.Join(pkiDir, "node.crt")
+	err = pki.GenerateCertificateRequest("test-node", nodeKeyPath, nodeCSRPath)
+	if err != nil {
+		t.Fatalf("Failed to generate node key and CSR: %v", err)
+	}
+	err = pki.SignCertificateRequest(caKeyPath, caCertPath, nodeCSRPath, nodeCertPath, 24*time.Hour)
+	if err != nil {
+		t.Fatalf("Failed to sign node CSR: %v", err)
+	}
+
+	// Create a test server that requires client certificates
+	server := httptest.NewTLSServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
+		// Verify the request path
+		if r.URL.Path != "/v1alpha1/nodes/test-node/status" {
+			t.Errorf("Expected path /v1alpha1/nodes/test-node/status, got %s", r.URL.Path)
+			http.Error(w, "Invalid path", http.StatusBadRequest)
+			return
+		}
+
+		// Verify the request method
+		if r.Method != "POST" {
+			t.Errorf("Expected method POST, got %s", r.Method)
+			http.Error(w, "Invalid method", http.StatusMethodNotAllowed)
+			return
+		}
+
+		// Parse the request body
+		var status NodeStatus
+		decoder := json.NewDecoder(r.Body)
+		if err := decoder.Decode(&status); err != nil {
+			t.Errorf("Failed to decode request body: %v", err)
+			http.Error(w, "Invalid request body", http.StatusBadRequest)
+			return
+		}
+
+		// Verify the node name
+		if status.NodeName != "test-node" {
+			t.Errorf("Expected node name test-node, got %s", status.NodeName)
+			http.Error(w, "Invalid node name", http.StatusBadRequest)
+			return
+		}
+
+		// Verify that resources are present
+		if status.Resources.Capacity.CPU == "" || status.Resources.Capacity.Memory == "" {
+			t.Errorf("Missing resource capacity information")
+			http.Error(w, "Missing resource information", http.StatusBadRequest)
+			return
+		}
+
+		// Return success
+		w.WriteHeader(http.StatusOK)
+	}))
+	defer server.Close()
+
+	// Configure the server to require client certificates
+	server.TLS.ClientAuth = tls.RequireAndVerifyClientCert
+	server.TLS.ClientCAs = x509.NewCertPool()
+	caCertData, err := os.ReadFile(caCertPath)
+	if err != nil {
+		t.Fatalf("Failed to read CA certificate: %v", err)
+	}
+	server.TLS.ClientCAs.AppendCertsFromPEM(caCertData)
+
+	// Extract the host:port from the server URL
+	serverURL := server.URL
+	hostPort := serverURL[8:] // Remove "https://" prefix
+
+	// Create an agent
+	agent, err := NewAgent("test-node", "test-uid", hostPort, "192.168.1.100", pkiDir, 1)
+	if err != nil {
+		t.Fatalf("Failed to create agent: %v", err)
+	}
+
+	// Setup mTLS client
+	err = agent.SetupMTLSClient()
+	if err != nil {
+		t.Fatalf("Failed to setup mTLS client: %v", err)
+	}
+
+	// Create a context with timeout
+	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
+	defer cancel()
+
+	// Start heartbeat
+	err = agent.StartHeartbeat(ctx)
+	if err != nil {
+		t.Fatalf("Failed to start heartbeat: %v", err)
+	}
+
+	// Wait for at least one heartbeat
+	time.Sleep(2 * time.Second)
+
+	// Stop heartbeat
+	agent.StopHeartbeat()
+
+	// Test passed if we got here without errors
+	fmt.Println("Agent heartbeat test passed")
+}

internal/api/node_status_handler.go

@@ -0,0 +1,108 @@
+package api
+
+import (
+	"encoding/json"
+	"fmt"
+	"io"
+	"log"
+	"net/http"
+	"strings"
+	"time"
+
+	"git.dws.rip/dubey/kat/internal/store"
+)
+
+// NodeStatusRequest represents the data sent by an agent in a heartbeat
+type NodeStatusRequest struct {
+	NodeName    string    `json:"nodeName"`
+	NodeUID     string    `json:"nodeUID"`
+	Timestamp   time.Time `json:"timestamp"`
+	Resources   struct {
+		Capacity    map[string]string `json:"capacity"`
+		Allocatable map[string]string `json:"allocatable"`
+	} `json:"resources"`
+	WorkloadInstances []struct {
+		WorkloadName  string `json:"workloadName"`
+		Namespace     string `json:"namespace"`
+		InstanceID    string `json:"instanceID"`
+		ContainerID   string `json:"containerID"`
+		ImageID       string `json:"imageID"`
+		State         string `json:"state"`
+		ExitCode      int    `json:"exitCode"`
+		HealthStatus  string `json:"healthStatus"`
+		Restarts      int    `json:"restarts"`
+	} `json:"workloadInstances,omitempty"`
+	OverlayNetwork struct {
+		Status       string `json:"status"`
+		LastPeerSync string `json:"lastPeerSync"`
+	} `json:"overlayNetwork"`
+}
+
+// NewNodeStatusHandler creates a handler for node status updates
+func NewNodeStatusHandler(stateStore store.StateStore) http.HandlerFunc {
+	return func(w http.ResponseWriter, r *http.Request) {
+		// Extract node name from URL path
+		pathParts := strings.Split(r.URL.Path, "/")
+		if len(pathParts) < 4 {
+			http.Error(w, "Invalid URL path", http.StatusBadRequest)
+			return
+		}
+		nodeName := pathParts[len(pathParts)-2] // /v1alpha1/nodes/{nodeName}/status
+
+		log.Printf("Received status update from node: %s", nodeName)
+
+		// Read and parse the request body
+		body, err := io.ReadAll(r.Body)
+		if err != nil {
+			log.Printf("Failed to read request body: %v", err)
+			http.Error(w, "Failed to read request body", http.StatusBadRequest)
+			return
+		}
+		defer r.Body.Close()
+
+		var statusReq NodeStatusRequest
+		if err := json.Unmarshal(body, &statusReq); err != nil {
+			log.Printf("Failed to parse status request: %v", err)
+			http.Error(w, "Failed to parse status request", http.StatusBadRequest)
+			return
+		}
+
+		// Validate that the node name in the URL matches the one in the request
+		if statusReq.NodeName != nodeName {
+			log.Printf("Node name mismatch: %s (URL) vs %s (body)", nodeName, statusReq.NodeName)
+			http.Error(w, "Node name mismatch", http.StatusBadRequest)
+			return
+		}
+
+		// Store the node status in etcd
+		nodeStatusKey := fmt.Sprintf("/kat/nodes/status/%s", nodeName)
+		nodeStatus := map[string]interface{}{
+			"lastHeartbeat": time.Now().Unix(),
+			"status":        "Ready",
+			"resources":     statusReq.Resources,
+			"network":       statusReq.OverlayNetwork,
+		}
+
+		// Add workload instances if present
+		if len(statusReq.WorkloadInstances) > 0 {
+			nodeStatus["workloadInstances"] = statusReq.WorkloadInstances
+		}
+
+		nodeStatusData, err := json.Marshal(nodeStatus)
+		if err != nil {
+			log.Printf("Failed to marshal node status: %v", err)
+			http.Error(w, "Failed to marshal node status", http.StatusInternalServerError)
+			return
+		}
+
+		log.Printf("Storing node status in etcd at key: %s", nodeStatusKey)
+		if err := stateStore.Put(r.Context(), nodeStatusKey, nodeStatusData); err != nil {
+			log.Printf("Failed to store node status: %v", err)
+			http.Error(w, "Failed to store node status", http.StatusInternalServerError)
+			return
+		}
+
+		log.Printf("Successfully stored status update for node: %s", nodeName)
+		w.WriteHeader(http.StatusOK)
+	}
+}

internal/api/node_status_handler_test.go

@@ -0,0 +1,108 @@
+package api
+
+import (
+	"bytes"
+	"context"
+	"encoding/json"
+	"net/http"
+	"net/http/httptest"
+	"testing"
+	"time"
+
+	"git.dws.rip/dubey/kat/internal/store"
+	"github.com/stretchr/testify/assert"
+	"github.com/stretchr/testify/mock"
+)
+
+func TestNodeStatusHandler(t *testing.T) {
+	// Create mock state store
+	mockStore := new(MockStateStore)
+	mockStore.On("Put", mock.Anything, mock.MatchedBy(func(key string) bool {
+		return key == "/kat/nodes/status/test-node"
+	}), mock.Anything).Return(nil)
+
+	// Create node status handler
+	handler := NewNodeStatusHandler(mockStore)
+
+	// Create test request
+	statusReq := NodeStatusRequest{
+		NodeName:  "test-node",
+		NodeUID:   "test-uid",
+		Timestamp: time.Now(),
+		Resources: struct {
+			Capacity    map[string]string `json:"capacity"`
+			Allocatable map[string]string `json:"allocatable"`
+		}{
+			Capacity: map[string]string{
+				"cpu":    "2000m",
+				"memory": "4096Mi",
+			},
+			Allocatable: map[string]string{
+				"cpu":    "1800m",
+				"memory": "3800Mi",
+			},
+		},
+		OverlayNetwork: struct {
+			Status       string `json:"status"`
+			LastPeerSync string `json:"lastPeerSync"`
+		}{
+			Status:       "connected",
+			LastPeerSync: time.Now().Format(time.RFC3339),
+		},
+	}
+	reqBody, err := json.Marshal(statusReq)
+	if err != nil {
+		t.Fatalf("Failed to marshal status request: %v", err)
+	}
+
+	// Create HTTP request
+	req := httptest.NewRequest("POST", "/v1alpha1/nodes/test-node/status", bytes.NewBuffer(reqBody))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+
+	// Call handler
+	handler(w, req)
+
+	// Check response
+	resp := w.Result()
+	defer resp.Body.Close()
+	assert.Equal(t, http.StatusOK, resp.StatusCode)
+
+	// Verify mock was called
+	mockStore.AssertExpectations(t)
+}
+
+func TestNodeStatusHandlerNameMismatch(t *testing.T) {
+	// Create mock state store
+	mockStore := new(MockStateStore)
+
+	// Create node status handler
+	handler := NewNodeStatusHandler(mockStore)
+
+	// Create test request with mismatched node name
+	statusReq := NodeStatusRequest{
+		NodeName:  "wrong-node", // This doesn't match the URL path
+		NodeUID:   "test-uid",
+		Timestamp: time.Now(),
+	}
+	reqBody, err := json.Marshal(statusReq)
+	if err != nil {
+		t.Fatalf("Failed to marshal status request: %v", err)
+	}
+
+	// Create HTTP request
+	req := httptest.NewRequest("POST", "/v1alpha1/nodes/test-node/status", bytes.NewBuffer(reqBody))
+	req.Header.Set("Content-Type", "application/json")
+	w := httptest.NewRecorder()
+
+	// Call handler
+	handler(w, req)
+
+	// Check response - should be bad request due to name mismatch
+	resp := w.Result()
+	defer resp.Body.Close()
+	assert.Equal(t, http.StatusBadRequest, resp.StatusCode)
+
+	// Verify mock was not called
+	mockStore.AssertNotCalled(t, "Put", mock.Anything, mock.Anything, mock.Anything)
+}

internal/api/server.go

@@ -142,4 +142,5 @@ func (s *Server) RegisterJoinHandler(handler http.HandlerFunc) {
 // RegisterNodeStatusHandler registers the handler for node status updates
 func (s *Server) RegisterNodeStatusHandler(handler http.HandlerFunc) {
 	s.router.HandleFunc("POST", "/v1alpha1/nodes/{nodeName}/status", handler)
+	log.Printf("Registered node status handler at /v1alpha1/nodes/{nodeName}/status")
 }

internal/cli/join.go

@@ -36,7 +36,7 @@ type JoinResponse struct {
 }
 
 // JoinCluster sends a join request to the leader and processes the response
-func JoinCluster(leaderAPI, advertiseAddr, nodeName, leaderCACert string, pkiDir string) error {
+func JoinCluster(leaderAPI, advertiseAddr, nodeName, leaderCACert string, pkiDir string) (*JoinResponse, error) {
 	// Create PKI directory if it doesn't exist
 	if err := os.MkdirAll(pkiDir, 0700); err != nil {
 		return fmt.Errorf("failed to create PKI directory: %w", err)
@@ -164,5 +164,5 @@ func JoinCluster(leaderAPI, advertiseAddr, nodeName, leaderCACert string, pkiDir
 		log.Printf("Etcd join instructions: %s", joinResp.EtcdJoinInstructions)
 	}
 
-	return nil
+	return &joinResp, nil
 }