package context import ( "bytes" "errors" "fmt" "io" "os" "github.com/docker/cli/cli" "github.com/docker/cli/cli/command" "github.com/docker/cli/cli/context/kubernetes" "github.com/docker/cli/cli/context/store" "github.com/spf13/cobra" "k8s.io/client-go/tools/clientcmd" ) // ExportOptions are the options used for exporting a context type ExportOptions struct { Kubeconfig bool ContextName string Dest string } func newExportCommand(dockerCli command.Cli) *cobra.Command { opts := &ExportOptions{} cmd := &cobra.Command{ Use: "export [OPTIONS] CONTEXT [FILE|-]", Short: "Export a context to a tar or kubeconfig file", Args: cli.RequiresRangeArgs(1, 2), RunE: func(cmd *cobra.Command, args []string) error { opts.ContextName = args[0] if len(args) == 2 { opts.Dest = args[1] } else { opts.Dest = opts.ContextName if opts.Kubeconfig { opts.Dest += ".kubeconfig" } else { opts.Dest += ".dockercontext" } } return RunExport(dockerCli, opts) }, } flags := cmd.Flags() flags.BoolVar(&opts.Kubeconfig, "kubeconfig", false, "Export as a kubeconfig file") return cmd } func writeTo(dockerCli command.Cli, reader io.Reader, dest string) error { var writer io.Writer var printDest bool if dest == "-" { if dockerCli.Out().IsTerminal() { return errors.New("cowardly refusing to export to a terminal, please specify a file path") } writer = dockerCli.Out() } else { f, err := os.OpenFile(dest, os.O_RDWR|os.O_CREATE|os.O_EXCL, 0600) if err != nil { return err } defer f.Close() writer = f printDest = true } if _, err := io.Copy(writer, reader); err != nil { return err } if printDest { fmt.Fprintf(dockerCli.Err(), "Written file %q\n", dest) } return nil } // RunExport exports a Docker context func RunExport(dockerCli command.Cli, opts *ExportOptions) error { if err := validateContextName(opts.ContextName); err != nil { return err } ctxMeta, err := dockerCli.ContextStore().GetContextMetadata(opts.ContextName) if err != nil { return err } if !opts.Kubeconfig { reader := store.Export(opts.ContextName, dockerCli.ContextStore()) defer reader.Close() return writeTo(dockerCli, reader, opts.Dest) } kubernetesEndpointMeta := kubernetes.EndpointFromContext(ctxMeta) if kubernetesEndpointMeta == nil { return fmt.Errorf("context %q has no kubernetes endpoint", opts.ContextName) } kubernetesEndpoint, err := kubernetesEndpointMeta.WithTLSData(dockerCli.ContextStore(), opts.ContextName) if err != nil { return err } kubeConfig := kubernetesEndpoint.KubernetesConfig() rawCfg, err := kubeConfig.RawConfig() if err != nil { return err } data, err := clientcmd.Write(rawCfg) if err != nil { return err } return writeTo(dockerCli, bytes.NewBuffer(data), opts.Dest) }