createCluster/network: add basic support for hostnetwork mode in docker

cmd/create/createCluster.go

@@ -170,6 +170,9 @@ func parseCreateClusterCmd(cmd *cobra.Command, args []string, createClusterOpts
 		network.Name = networkName
 		network.External = true
 	}
+	if networkName == "host" && (masterCount+workerCount) > 1 {
+		log.Fatalln("Can only run a single node in hostnetwork mode")
+	}
 
 	// --secret
 	secret, err := cmd.Flags().GetString("secret")

pkg/runtimes/docker/network.go

@@ -93,3 +93,14 @@ func (d Docker) DeleteNetwork(ID string) error {
 	// (3) delete network
 	return docker.NetworkRemove(ctx, ID)
 }
+
+// GetNetwork gets information about a network by its ID
+func GetNetwork(ID string) (types.NetworkResource, error) {
+	ctx := context.Background()
+	docker, err := client.NewClientWithOpts(client.FromEnv, client.WithAPIVersionNegotiation())
+	if err != nil {
+		log.Errorln("Failed to create docker client")
+		return types.NetworkResource{}, err
+	}
+	return docker.NetworkInspect(ctx, ID, types.NetworkInspectOptions{})
+}

pkg/runtimes/docker/translate.go

@@ -86,11 +86,17 @@ func TranslateNodeToContainer(node *k3d.Node) (*NodeInDocker, error) {
 	}
 	containerConfig.ExposedPorts = exposedPorts
 	hostConfig.PortBindings = portBindings
-
 	/* Network */
 	networkingConfig.EndpointsConfig = map[string]*network.EndpointSettings{
 		node.Network: {},
 	}
+	netInfo, err := GetNetwork(node.Network)
+	if err != nil {
+		log.Warnln("Failed to get network information")
+		log.Warnln(err)
+	} else if netInfo.Driver == "host" {
+		hostConfig.NetworkMode = "host"
+	}
 
 	return &NodeInDocker{
 		ContainerConfig:  containerConfig,

tests/test_basic.sh

@@ -7,8 +7,8 @@ CURR_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
 source "$CURR_DIR/common.sh"
 
 info "Creating two clusters..."
-$EXE --verbose create cluster c1 --wait --timeout 60 --api-port 6443 || failed "could not create cluster c1"
-$EXE --verbose create cluster c2 --wait --timeout 60 --api-port 6444 || failed "could not create cluster c2"
+$EXE --verbose create cluster c1 --wait --timeout 60s --api-port 6443 || failed "could not create cluster c1"
+$EXE --verbose create cluster c2 --wait --timeout 60s --api-port 6444 || failed "could not create cluster c2"
 
 info "Checking we have access to both clusters..."
 check_k3d_clusters "c1" "c2" || failed "error checking cluster"

tests/test_multi_master.sh

@@ -7,7 +7,7 @@ CURR_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" >/dev/null 2>&1 && pwd )"
 source "$CURR_DIR/common.sh"
 
 info "Creating cluster multimaster..."
-$EXE create cluster "multimaster" --masters 3 --api-port 6443 --wait --timeout 360 || failed "could not create cluster multimaster"
+$EXE --verbose create cluster "multimaster" --masters 3 --api-port 6443 --wait --timeout 360s || failed "could not create cluster multimaster"
 
 info "Checking we have access to the cluster..."
 check_k3d_clusters "multimaster" || failed "error checking cluster"