createNode: update nginx masterlb with new master node

- if --role=master, update nginx config and reload it

pkg/cluster/cluster.go

@@ -427,7 +427,7 @@ func populateClusterFieldsFromLabels(cluster *k3d.Cluster) error {
 	return nil
 }
 
-// GetCluster returns an existing cluster
+// GetCluster returns an existing cluster with all fields and node lists populated
 func GetCluster(cluster *k3d.Cluster, runtime k3drt.Runtime) (*k3d.Cluster, error) {
 	// get nodes that belong to the selected cluster
 	nodes, err := runtime.GetNodesByLabel(map[string]string{"k3d.cluster": cluster.Name})

pkg/cluster/loadbalancer.go

@@ -0,0 +1,59 @@
+/*
+Copyright © 2020 The k3d Author(s)
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
+*/
+package cluster
+
+import (
+	"fmt"
+
+	"github.com/rancher/k3d/pkg/runtimes"
+	k3d "github.com/rancher/k3d/pkg/types"
+	log "github.com/sirupsen/logrus"
+)
+
+// AddMasterToLoadBalancer adds a new master node to the loadbalancer configuration
+func AddMasterToLoadBalancer(runtime runtimes.Runtime, cluster *k3d.Cluster, newNode *k3d.Node) error {
+	// find the LoadBalancer for the target cluster
+	masterNodes := ""
+	var loadbalancer *k3d.Node
+	for _, node := range cluster.Nodes {
+		if node.Role == k3d.LoadBalancerRole { // get the loadbalancer we want to update
+			loadbalancer = node
+		} else if node.Role == k3d.MasterRole { // create a list of master nodes
+			masterNodes += node.Name + ","
+		}
+	}
+	if loadbalancer == nil {
+		return fmt.Errorf("Failed to find loadbalancer for cluster '%s'", cluster.Name)
+	}
+	masterNodes += newNode.Name // append the new master node to the end of the list
+
+	log.Debugf("SERVERS=%s", masterNodes)
+
+	command := fmt.Sprintf("SERVERS=%s %s", masterNodes, "confd -onetime -backend env && nginx -s reload")
+	if err := runtime.ExecInNode(loadbalancer, []string{"sh", "-c", command}); err != nil {
+		log.Errorln("Failed to update loadbalancer configuration")
+		return err
+	}
+
+	return nil
+
+}

pkg/cluster/node.go

@@ -94,7 +94,19 @@ func AddNodeToCluster(runtime runtimes.Runtime, node *k3d.Node, cluster *k3d.Clu
 
 	log.Debugf("Resulting node %+v", node)
 
-	return CreateNode(node, runtime)
+	if err := CreateNode(node, runtime); err != nil {
+		return err
+	}
+
+	// if it's a master node, then update the loadbalancer configuration to include it
+	if node.Role == k3d.MasterRole {
+		if err := AddMasterToLoadBalancer(runtime, cluster, node); err != nil {
+			log.Errorln("Failed to add new master node to cluster loadbalancer")
+			return err
+		}
+	}
+
+	return nil
 }
 
 // CreateNodes creates a list of nodes
@@ -196,7 +208,7 @@ func GetNodes(runtime runtimes.Runtime) ([]*k3d.Node, error) {
 	return nodes, nil
 }
 
-// GetNode returns an existing cluster
+// GetNode returns a node matching the specified node fields
 func GetNode(node *k3d.Node, runtime runtimes.Runtime) (*k3d.Node, error) {
 	// get node
 	node, err := runtime.GetNode(node)

pkg/runtimes/docker/translate.go

@@ -23,6 +23,8 @@ THE SOFTWARE.
 package docker
 
 import (
+	"strings"
+
 	"github.com/docker/docker/api/types"
 	docker "github.com/docker/docker/api/types/container"
 	"github.com/docker/docker/api/types/network"
@@ -107,10 +109,10 @@ func TranslateNodeToContainer(node *k3d.Node) (*NodeInDocker, error) {
 // TranslateContainerToNode translates a docker container object into a k3d node representation
 func TranslateContainerToNode(cont *types.Container) (*k3d.Node, error) {
 	node := &k3d.Node{
-		Name:   cont.Names[0],
+		Name:   strings.TrimPrefix(cont.Names[0], "/"), // container name with leading '/' cut off
 		Image:  cont.Image,
 		Labels: cont.Labels,
-		Role:   k3d.NodeRoles[cont.Labels["k3d.role"]], // TODO: what if this is not present?
+		Role:   k3d.NodeRoles[cont.Labels["k3d.role"]],
 		// TODO: all the rest
 	}
 	return node, nil