runtimes: enable log export feature

cmd/cluster/cluster.go

@@ -48,7 +48,9 @@ func NewCmdCluster() *cobra.Command {
 		NewCmdClusterStop(),
 		NewCmdClusterDelete(),
 		NewCmdClusterList(),
-		NewCmdClusterEdit())
+		NewCmdClusterEdit(),
+		NewCmdClusterExportLogs(),
+	)
 
 	// add flags
 

cmd/cluster/clusterExportLogs.go

@@ -0,0 +1,68 @@
+/*
+Copyright © 2020-2023 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 (
+	"github.com/k3d-io/k3d/v5/cmd/util"
+	"github.com/k3d-io/k3d/v5/pkg/client"
+	l "github.com/k3d-io/k3d/v5/pkg/logger"
+	"github.com/k3d-io/k3d/v5/pkg/runtimes"
+	k3d "github.com/k3d-io/k3d/v5/pkg/types"
+	"github.com/spf13/cobra"
+)
+
+var exportPath string
+
+func NewCmdClusterExportLogs() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:               "export-logs CLUSTER [PATH]",
+		Short:             "Export logs of a k3d cluster",
+		Long:              `Export logs of a k3d cluster.`,
+		ValidArgsFunction: util.ValidArgsAvailableClusters,
+		Run: func(cmd *cobra.Command, args []string) {
+			cluster := parseExportLogsCmd(cmd, args)
+
+			for _, node := range cluster.Nodes {
+				if err := runtimes.SelectedRuntime.ExportLogsFromNode(cmd.Context(), node, exportPath); err != nil {
+					l.Log().Fatalln(err)
+				}
+			}
+		},
+	}
+
+	cmd.Flags().StringVarP(&exportPath, "path", "p", "", "Path to export the logs to")
+
+	return cmd
+}
+
+func parseExportLogsCmd(cmd *cobra.Command, args []string) *k3d.Cluster {
+	if len(args) == 0 || len(args[0]) == 0 {
+		l.Log().Fatalln("No cluster name given")
+	}
+
+	cluster, err := client.ClusterGet(cmd.Context(), runtimes.SelectedRuntime, &k3d.Cluster{Name: args[0]})
+	if err != nil {
+		l.Log().Fatalln(err)
+	}
+	return cluster
+}

cmd/node/node.go

@@ -47,7 +47,9 @@ func NewCmdNode() *cobra.Command {
 		NewCmdNodeStop(),
 		NewCmdNodeDelete(),
 		NewCmdNodeList(),
-		NewCmdNodeEdit())
+		NewCmdNodeEdit(),
+		NewCmdNodeExportLogs(),
+	)
 
 	// add flags
 

cmd/node/nodeExportLogs.go

@@ -0,0 +1,69 @@
+/*
+Copyright © 2020-2024 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 node
+
+import (
+	"os"
+
+	"github.com/k3d-io/k3d/v5/cmd/util"
+	"github.com/k3d-io/k3d/v5/pkg/client"
+	l "github.com/k3d-io/k3d/v5/pkg/logger"
+	"github.com/k3d-io/k3d/v5/pkg/runtimes"
+	k3d "github.com/k3d-io/k3d/v5/pkg/types"
+	"github.com/spf13/cobra"
+)
+
+var exportPath string
+
+func NewCmdNodeExportLogs() *cobra.Command {
+	cmd := &cobra.Command{
+		Use:               "export-logs NODE",
+		Short:             "Export logs of a k3d node",
+		Long:              `Export logs of a k3d node.`,
+		ValidArgsFunction: util.ValidArgsAvailableNodes,
+		Run: func(cmd *cobra.Command, args []string) {
+			node := parseExportLogsCmd(cmd, args)
+			l.Log().Fatalln(runtimes.SelectedRuntime.ExportLogsFromNode(cmd.Context(), node, exportPath))
+		},
+	}
+
+	cwd, err := os.Getwd()
+	if err != nil {
+		l.Log().Fatalln(err)
+	}
+	cmd.Flags().StringVarP(&exportPath, "path", "p", cwd, "Path to export the logs to")
+
+	return cmd
+}
+
+func parseExportLogsCmd(cmd *cobra.Command, args []string) *k3d.Node {
+	if len(args) == 0 || len(args[0]) == 0 {
+		l.Log().Fatalln("No node name given")
+	}
+
+	node, err := client.NodeGet(cmd.Context(), runtimes.SelectedRuntime, &k3d.Node{Name: args[0]})
+	if err != nil {
+		l.Log().Fatalln(err)
+	}
+	return node
+}

pkg/runtimes/docker/docker.go

@@ -29,6 +29,7 @@ import (
 	"os"
 
 	l "github.com/k3d-io/k3d/v5/pkg/logger"
+	k3d "github.com/k3d-io/k3d/v5/pkg/types"
 )
 
 type Docker struct{}
@@ -42,6 +43,11 @@ func (d Docker) ID() string {
 	return "docker"
 }
 
+var roleBasedExportPath = map[k3d.Role][]string{
+	k3d.ServerRole: {"/var/log", "/var/lib/rancher/k3s/agent/containerd/containerd.log"},
+	k3d.AgentRole:  {"/var/log", "/var/lib/rancher/k3s/agent/containerd/containerd.log"},
+}
+
 // GetHost returns the docker daemon host
 func (d Docker) GetHost() string {
 	// a) docker-machine

pkg/runtimes/docker/node.go

@@ -29,6 +29,8 @@ import (
 	"errors"
 	"fmt"
 	"io"
+	"os"
+	"path/filepath"
 	"time"
 
 	"github.com/docker/docker/api/types"
@@ -493,3 +495,45 @@ func (d Docker) RenameNode(ctx context.Context, node *k3d.Node, newName string)
 
 	return docker.ContainerRename(ctx, container.ID, newName)
 }
+
+func (d Docker) ExportLogsFromNode(ctx context.Context, node *k3d.Node, dstPath string) error {
+	destinationPath := filepath.Join(dstPath, node.Name)
+
+	err := os.MkdirAll(destinationPath, os.FileMode(os.ModePerm))
+	if err != nil {
+		return fmt.Errorf("failed to create destination directory '%s': %w", destinationPath, err)
+	}
+	c, err := getNodeContainer(ctx, node)
+	if err != nil {
+		return fmt.Errorf("failed to get container for node '%s': %w", node.Name, err)
+	}
+
+	// create docker client
+	docker, err := GetDockerClient()
+	if err != nil {
+		return fmt.Errorf("failed to get docker client: %w", err)
+	}
+	defer docker.Close()
+
+	reader, err := docker.ContainerLogs(ctx, c.ID, container.LogsOptions{Details: true, ShowStdout: true, ShowStderr: true})
+	if err != nil {
+		return fmt.Errorf("failed to get logs from container '%s': %w", c.ID, err)
+	}
+	defer reader.Close()
+
+	err = readerToFile(reader, filepath.Join(dstPath, fmt.Sprintf("%s.log", node.Name)))
+	if err != nil {
+		return fmt.Errorf("failed to write logs to file: %w", err)
+	}
+
+	for _, srcPath := range roleBasedExportPath[node.Role] {
+		contentReader, _, err := docker.CopyFromContainer(ctx, c.ID, srcPath)
+		if err != nil {
+			return fmt.Errorf("failed to copy files from container '%s': %w", c.ID, err)
+		}
+		if err := untarReader(ctx, docker, c.ID, contentReader, destinationPath); err != nil {
+			return fmt.Errorf("failed to untar files from container '%s': %w", c.ID, err)
+		}
+	}
+	return nil
+}

pkg/runtimes/docker/util.go

@@ -28,6 +28,7 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"path/filepath"
 	"regexp"
 	"strings"
 
@@ -211,3 +212,96 @@ func isAttachedToNetwork(node *k3d.Node, network string) bool {
 	}
 	return false
 }
+
+func readerToFile(reader io.Reader, target string) error {
+	file, err := os.OpenFile(target, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, os.FileMode(0600))
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+	if _, err := io.Copy(file, reader); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func copyFile(tarReader *tar.Reader, target string, mode os.FileMode) error {
+	file, err := os.OpenFile(target, os.O_CREATE|os.O_WRONLY|os.O_TRUNC, mode)
+	if err != nil {
+		return err
+	}
+	defer file.Close()
+
+	if _, err := io.Copy(file, tarReader); err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func copyOriginalContent(cli client.APIClient, ctx context.Context, containerID, linkTarget, target string) error {
+	reader, _, err := cli.CopyFromContainer(ctx, containerID, linkTarget)
+	if err != nil {
+		return err
+	}
+	defer reader.Close()
+
+	tarReader := tar.NewReader(reader)
+	header, err := tarReader.Next()
+	if err != nil {
+		return err
+	}
+
+	if header.Typeflag == tar.TypeReg {
+		if err := copyFile(tarReader, target, os.FileMode(header.Mode)); err != nil {
+			return err
+		}
+	} else if header.Typeflag == tar.TypeDir {
+		// If the link target is a directory, recursively copy its contents
+		if err := untarReader(ctx, cli, containerID, reader, target); err != nil {
+			return err
+		}
+	} else {
+		return fmt.Errorf("unsupported symlink target file type: %v", header.Typeflag)
+	}
+
+	return nil
+}
+
+func untarReader(ctx context.Context, cli client.APIClient, containerID string, reader io.Reader, dstPath string) error {
+	tarReader := tar.NewReader(reader)
+
+	for {
+		header, err := tarReader.Next()
+		if err == io.EOF {
+			break
+		}
+		if err != nil {
+			return err
+		}
+
+		target := filepath.Join(dstPath, header.Name)
+
+		switch header.Typeflag {
+		case tar.TypeDir:
+			if err := os.MkdirAll(target, os.FileMode(header.Mode)); err != nil {
+				return err
+			}
+		case tar.TypeReg:
+			if err := copyFile(tarReader, target, os.FileMode(header.Mode)); err != nil {
+				return err
+			}
+		case tar.TypeSymlink:
+			// Resolve the symlink and copy the original content
+			linkTarget := header.Linkname
+			if err := copyOriginalContent(cli, ctx, containerID, linkTarget, target); err != nil {
+				return err
+			}
+		default:
+			return fmt.Errorf("unsupported file type: %v", header.Typeflag)
+		}
+	}
+
+	return nil
+}

pkg/runtimes/runtime.go

@@ -81,6 +81,7 @@ type Runtime interface {
 	DisconnectNodeFromNetwork(context.Context, *k3d.Node, string) error // @param context, node, network name
 	Info() (*runtimeTypes.RuntimeInfo, error)
 	GetNetwork(context.Context, *k3d.ClusterNetwork) (*k3d.ClusterNetwork, error) // @param context, network (so we can filter by name or by id)
+	ExportLogsFromNode(context.Context, *k3d.Node, string) error                  // @param context, node, source, destination
 }
 
 // GetRuntime checks, if a given name is represented by an implemented k3d runtime and returns it