add utils

.gitignore

@@ -16,4 +16,5 @@ _dist/
 *.out
 
 # Editors
-.vscode/
+.vscode/
+.local/

pkg/cluster/cluster.go

@@ -21,11 +21,13 @@ THE SOFTWARE.
 */
 package cluster
 
-import "github.com/rancher/k3d/pkg/types"
+import (
+	"github.com/rancher/k3d/pkg/types"
+)
 
 // CreateCluster creates a new cluster consisting of
 // - some containerized k3s nodes
 // - a docker network
-func CreateCluster(clusterSpec *types.Cluster) error {
+func CreateCluster(cluster *types.Cluster) error {
 	return nil
 }

pkg/cluster/clusterName.go

@@ -0,0 +1,69 @@
+/*
+Copyright © 2019 Thorsten Klein <iwilltry42@gmail.com>
+
+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/types"
+)
+
+// CheckClusterName ensures that a cluster name is also a valid host name according to RFC 1123.
+// We further restrict the length of the cluster name to maximum 'clusterNameMaxSize'
+// so that we can construct the host names based on the cluster name, and still stay
+// within the 64 characters limit.
+func CheckClusterName(name string) error {
+	if err := ValidateHostname(name); err != nil {
+		return fmt.Errorf("Invalid cluster name. %+v", ValidateHostname(name))
+	}
+	if len(name) > types.DefaultClusterNameMaxLength {
+		return fmt.Errorf("Cluster name must be <= %d characters, but has %d", types.DefaultClusterNameMaxLength, len(name))
+	}
+	return nil
+}
+
+// ValidateHostname ensures that a cluster name is also a valid host name according to RFC 1123.
+func ValidateHostname(name string) error {
+
+	if len(name) == 0 {
+		return fmt.Errorf("No name provided")
+	}
+
+	if name[0] == '-' || name[len(name)-1] == '-' {
+		return fmt.Errorf("Hostname '%s' must not start or end with '-' (dash)", name)
+	}
+
+	for _, c := range name {
+		switch {
+		case '0' <= c && c <= '9':
+		case 'a' <= c && c <= 'z':
+		case 'A' <= c && c <= 'Z':
+		case c == '-':
+			break
+		default:
+			return fmt.Errorf("Hostname '%s' contains characters other than 'Aa-Zz', '0-9' or '-'", name)
+
+		}
+	}
+
+	return nil
+}

pkg/runtimes/docker/container.go

@@ -32,7 +32,7 @@ import (
 
 // createContainer creates a new docker container
 // @return containerID, error
-func createContainer(ID string) (string, error) {
+func createContainer(types.Container) (string, error) {
 	return "", nil
 }
 

pkg/runtimes/docker/network.go

@@ -48,7 +48,6 @@ func CreateNetworkIfNotExist(clusterName string) (string, error) {
 	// (1) configure list filters
 	args := GetDefaultObjectLabelsFilter(clusterName)
 	args.Add("name", networkName)
-	// TODO: filter for label: cluster=<clusterName>?
 
 	// (2) get filtered list of networks
 	networkList, err := docker.NetworkList(ctx, types.NetworkListOptions{

pkg/runtimes/docker/util.go

@@ -0,0 +1,39 @@
+/*
+Copyright © 2019 Thorsten Klein <iwilltry42@gmail.com>
+
+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 docker
+
+import (
+	"fmt"
+
+	"github.com/docker/docker/api/types/filters"
+	k3d "github.com/rancher/k3d/pkg/types"
+)
+
+// GetDefaultObjectLabelsFilter returns docker type filters created from k3d labels
+func GetDefaultObjectLabelsFilter(clusterName string) filters.Args {
+	filters := filters.NewArgs()
+	for key, value := range k3d.DefaultObjectLabels {
+		filters.Add("label", fmt.Sprintf("%s=%s", key, value))
+	}
+	filters.Add("label", fmt.Sprintf("cluster=%s", clusterName))
+	return filters
+}

pkg/types/types.go

@@ -26,6 +26,12 @@ import "fmt"
 // DefaultClusterName specifies the default name used for newly created clusters
 const DefaultClusterName = "k3s-default"
 
+// DefaultClusterNameMaxLength specifies the maximal length of a passed in cluster name
+// This restriction allows us to construct an name consisting of
+// <DefaultObjectNamePrefix[3]>-<ClusterName>-<TypeSuffix[5-10]>-<Counter[1-3]>
+// ... and still stay within the 64 character limit (e.g. of docker)
+const DefaultClusterNameMaxLength = 32
+
 // DefaultK3sImageRepo specifies the default image repository for the used k3s image
 const DefaultK3sImageRepo = "docker.io/rancher/k3s"
 
@@ -41,6 +47,7 @@ var DefaultObjectLabels = map[string]string{
 type Cluster struct {
 	Name    string
 	Network string
+	Secret  string
 	Nodes   []Node
 }