allow connections to non-dockerized k3s clusters

cli/commands.go

@@ -460,7 +460,7 @@ func AddNode(c *cli.Context) error {
 
 	// TODO: support this
 	if nodeRole == "server" {
-		return fmt.Errorf("ERROR: sorry, we don't support adding server nodes at the moment!")
+		return fmt.Errorf("ERROR: sorry, we don't support adding server nodes at the moment")
 	}
 
 	/* (0.2)
@@ -473,6 +473,22 @@ func AddNode(c *cli.Context) error {
 		image = fmt.Sprintf("%s/%s", defaultRegistry, image)
 	}
 
+	/* (0.3) BREAKOUT
+	 * --k3s <url>
+	 * Connect to a non-dockerized k3s server
+	 */
+
+	if c.IsSet("k3s") {
+		log.Printf("INFO: Adding new nodes to k3s [%s]\n", c.String("k3s"))
+		if _, err := createClusterNetwork(clusterName); err != nil {
+			return err
+		}
+		if err := addNodeToK3s(c, nodeRole, image); err != nil {
+			return err
+		}
+		return nil
+	}
+
 	/*
 	 * (1) Check cluster
 	 */
@@ -530,7 +546,7 @@ func AddNode(c *cli.Context) error {
 		}
 	}
 	if serverListenPort == "" {
-		return fmt.Errorf("ERROR: couldn't get https-listen-port form server contaienr")
+		return fmt.Errorf("ERROR: couldn't get https-listen-port form server container")
 	}
 
 	/*
@@ -600,15 +616,58 @@ func AddNode(c *cli.Context) error {
 
 	log.Printf("INFO: Adding %d %s-nodes to cluster %s...\n", nodeCount, nodeRole, clusterName)
 
-	if nodeRole == "agent" {
-		for suffix := highestExistingWorkerSuffix + 1; suffix < nodeCount+1+highestExistingWorkerSuffix; suffix++ {
-			workerContainerID, err := createWorker(clusterSpec, suffix)
-			if err != nil {
-				return fmt.Errorf("ERROR: Couldn't create %s-node!\n%+v", nodeRole, err)
-			}
-			log.Printf("INFO: Created %s-node with ID %s\n", nodeRole, workerContainerID)
-		}
+	if err := createNodes(clusterSpec, nodeRole, highestExistingWorkerSuffix+1, nodeCount); err != nil {
+		return err
 	}
 
 	return nil
 }
+
+func addNodeToK3s(c *cli.Context, nodeRole, image string) error {
+	env := []string{}
+
+	k3sURLEnvVar := fmt.Sprintf("K3S_URL=%s", c.String("k3s"))
+	k3sConnSecretEnvVar := fmt.Sprintf("K3S_SECRET=%s", c.String("k3s-secret"))
+	if c.IsSet("k3s-token") {
+		k3sConnSecretEnvVar = fmt.Sprintf("K3S_TOKEN=%s", c.String("k3s-token"))
+	}
+
+	env = append(env, k3sURLEnvVar, k3sConnSecretEnvVar)
+
+	clusterSpec := &ClusterSpec{
+		AgentArgs:         nil,
+		APIPort:           apiPort{},
+		AutoRestart:       false,
+		ClusterName:       c.String("name"),
+		Env:               env,
+		Image:             image,
+		NodeToPortSpecMap: nil,
+		PortAutoOffset:    0,
+		ServerArgs:        nil,
+		Verbose:           false,
+		Volumes:           nil,
+	}
+
+	if err := createNodes(clusterSpec, nodeRole, 0, c.Int("count")); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func createNodes(clusterSpec *ClusterSpec, role string, suffixNumberStart int, count int) error {
+	for suffix := suffixNumberStart; suffix < suffixNumberStart+count; suffix++ {
+		containerID := ""
+		var err error
+		if role == "agent" {
+			containerID, err = createWorker(clusterSpec, suffix)
+		} else if role == "server" {
+			containerID, err = createServer(clusterSpec)
+		}
+		if err != nil {
+			return fmt.Errorf("ERROR: Couldn't create %s-node!\n%+v", role, err)
+		}
+		log.Printf("INFO: Created %s-node with ID %s\n", role, containerID)
+	}
+	return nil
+}

cli/container.go

@@ -144,8 +144,18 @@ func createWorker(spec *ClusterSpec, postfix int) (string, error) {
 	containerLabels["cluster"] = spec.ClusterName
 
 	containerName := GetContainerName("worker", spec.ClusterName, postfix)
+	env := spec.Env
 
-	env := append(spec.Env, fmt.Sprintf("K3S_URL=https://k3d-%s-server:%s", spec.ClusterName, spec.APIPort.Port))
+	needServerURL := true
+	for _, envVar := range env {
+		if strings.Split(envVar, "=")[0] == "K3S_URL" {
+			needServerURL = false
+			break
+		}
+	}
+	if needServerURL {
+		env = append(spec.Env, fmt.Sprintf("K3S_URL=https://k3d-%s-server:%s", spec.ClusterName, spec.APIPort.Port))
+	}
 
 	// ports to be assigned to the server belong to roles
 	// all, server or <server-container-name>

main.go

@@ -131,9 +131,12 @@ func main() {
 			},
 			Action: run.CreateCluster,
 		},
+		/*
+		 * Add a new node to an existing k3d/k3s cluster (choosing k3d by default)
+		 */
 		{
 			Name:  "add-node",
-			Usage: "Add nodes to an existing k3d cluster",
+			Usage: "Add nodes to an existing k3d/k3s cluster (k3d by default)",
 			Flags: []cli.Flag{
 				cli.StringFlag{
 					Name:  "role, r",
@@ -142,7 +145,7 @@ func main() {
 				},
 				cli.StringFlag{
 					Name:  "name, n",
-					Usage: "Name of the clsuter that you want to add a node to",
+					Usage: "Name of the k3d cluster that you want to add a node to [only for node name if --k3s is set]",
 					Value: defaultK3sClusterName,
 				},
 				cli.IntFlag{
@@ -155,6 +158,21 @@ func main() {
 					Usage: "Specify a k3s image (Format: <repo>/<image>:<tag>)",
 					Value: fmt.Sprintf("%s:%s", defaultK3sImage, version.GetK3sVersion()),
 				},
+				/*
+				 * Connect to a non-dockerized k3s cluster
+				 */
+				cli.StringFlag{
+					Name:  "k3s",
+					Usage: "Add a k3d node to a non-k3d k3s cluster (specify k3s server URL like this `https://<host>:<port>`) [requires k3s-secret or k3s-token]",
+				},
+				cli.StringFlag{
+					Name:  "k3s-secret, s",
+					Usage: "Specify k3s cluster secret (or use --k3s-token to use a node token)",
+				},
+				cli.StringFlag{
+					Name:  "k3s-token, t",
+					Usage: "Specify k3s node token (or use --k3s-secret to use a cluster secret)[overrides k3s-secret]",
+				},
 			},
 			Action: run.AddNode,
 		},