Support bootstrap routes

Author: Neil Jerram

pkg/apis/config/v1alpha4/zz_generated.deepcopy.go

@@ -21,6 +21,7 @@ package constants
 const DefaultClusterName = "kind"
 
 const NodeLoopbackKey = "io.k8s.sigs.kind.loopback"
+const NodeRoutesKey = "io.k8s.sigs.kind.routes"
 
 /* node role value constants */
 const (

pkg/cluster/constants/constants.go

@@ -21,6 +21,7 @@ import (
 	"fmt"
 	"sigs.k8s.io/kind/pkg/errors"
 	"sigs.k8s.io/kind/pkg/internal/cluster/create/actions"
+	"strings"
 )
 
 // kubeadmInitAction implements action for executing the kubadm init
@@ -52,7 +53,7 @@ func (a *action) Execute(ctx *actions.ActionContext) error {
 				"ip",
 				"a",
 				"a",
-				loopAddress + "/32",
+				loopAddress+"/32",
 				"dev",
 				"lo",
 			)
@@ -61,6 +62,23 @@ func (a *action) Execute(ctx *actions.ActionContext) error {
 				return errors.Wrap(err, "failed to set loopback address")
 			}
 		}
+
+		routes, err := node.Routes()
+		if err != nil {
+			fmt.Printf("Loopback action error: %v\n", err)
+			continue
+		}
+		for _, route := range strings.Split(routes, ",") {
+			fmt.Printf("Install route: %v\n", route)
+			args := []string{"r", "a"}
+			args = append(args, strings.Split(route, " ")...)
+			cmd := node.Command("ip", args...)
+			err := cmd.Run()
+			if err != nil {
+				return errors.Wrap(err, "failed to install route")
+			}
+		}
+
 	}
 	return nil
 }

pkg/cluster/internal/create/actions/loopback/loopback.go

@@ -57,10 +57,25 @@ func (n *node) Loopback() (string, error) {
 	)
 	lines, err := exec.OutputLines(cmd)
 	if err != nil {
-		return "", errors.Wrap(err, "failed to get role for node")
+		return "", errors.Wrap(err, "failed to get loopback for node")
 	}
 	if len(lines) != 1 {
-		return "", errors.Errorf("failed to get role for node: output lines %d != 1", len(lines))
+		return "", errors.Errorf("failed to get loopback for node: output lines %d != 1", len(lines))
+	}
+	return lines[0], nil
+}
+
+func (n *node) Routes() (string, error) {
+	cmd := exec.Command("docker", "inspect",
+		"--format", fmt.Sprintf(`{{ index .Config.Labels "%s"}}`, constants.NodeRoutesKey),
+		n.name,
+	)
+	lines, err := exec.OutputLines(cmd)
+	if err != nil {
+		return "", errors.Wrap(err, "failed to get routes for node")
+	}
+	if len(lines) != 1 {
+		return "", errors.Errorf("failed to get routes for node: output lines %d != 1", len(lines))
 	}
 	return lines[0], nil
 }

pkg/cluster/internal/providers/docker/node.go

@@ -245,6 +245,7 @@ func runArgsForNode(node *config.Node, clusterIPFamily config.ClusterIPFamily, n
 		// label the node with the role ID
 		"--label", fmt.Sprintf("%s=%s", nodeRoleLabelKey, node.Role),
 		"--label", fmt.Sprintf("%s=%s", constants.NodeLoopbackKey, node.Loopback),
+		"--label", fmt.Sprintf("%s=%s", constants.NodeRoutesKey, strings.Join(node.Routes, ",")),
 		// running containers in a container requires privileged
 		// NOTE: we could try to replicate this with --cap-add, and use less
 		// privileges, but this flag also changes some mounts that are necessary

pkg/cluster/internal/providers/docker/provision.go

@@ -30,8 +30,9 @@ type Node interface {
 	// String should return the node name
 	String() string // see also: fmt.Stringer
 	// Role should return the node's role
-	Role() (string, error) // see also: pkg/cluster/constants
+	Role() (string, error)     // see also: pkg/cluster/constants
 	Loopback() (string, error) // see also: pkg/cluster/constants
+	Routes() (string, error)   // see also: pkg/cluster/constants
 	// TODO(bentheelder): should return node addresses more generally
 	// Possibly remove this method in favor of obtaining this detail with
 	// exec or from the provider

pkg/cluster/nodes/types.go

@@ -110,6 +110,8 @@ type Node struct {
 
 	// Loopback IP.
 	Loopback string
+
+	Routes []string
 }
 
 // NodeRole defines possible role for nodes in a Kubernetes cluster managed by `kind`