github.1git.de/docker/cli@v26.1.3+incompatible/cli/command/container/export.go (about)

     1  package container
     2  
     3  import (
     4  	"context"
     5  	"io"
     6  
     7  	"github.com/docker/cli/cli"
     8  	"github.com/docker/cli/cli/command"
     9  	"github.com/docker/cli/cli/command/completion"
    10  	"github.com/pkg/errors"
    11  	"github.com/spf13/cobra"
    12  )
    13  
    14  type exportOptions struct {
    15  	container string
    16  	output    string
    17  }
    18  
    19  // NewExportCommand creates a new `docker export` command
    20  func NewExportCommand(dockerCli command.Cli) *cobra.Command {
    21  	var opts exportOptions
    22  
    23  	cmd := &cobra.Command{
    24  		Use:   "export [OPTIONS] CONTAINER",
    25  		Short: "Export a container's filesystem as a tar archive",
    26  		Args:  cli.ExactArgs(1),
    27  		RunE: func(cmd *cobra.Command, args []string) error {
    28  			opts.container = args[0]
    29  			return runExport(cmd.Context(), dockerCli, opts)
    30  		},
    31  		Annotations: map[string]string{
    32  			"aliases": "docker container export, docker export",
    33  		},
    34  		ValidArgsFunction: completion.ContainerNames(dockerCli, true),
    35  	}
    36  
    37  	flags := cmd.Flags()
    38  
    39  	flags.StringVarP(&opts.output, "output", "o", "", "Write to a file, instead of STDOUT")
    40  
    41  	return cmd
    42  }
    43  
    44  func runExport(ctx context.Context, dockerCli command.Cli, opts exportOptions) error {
    45  	if opts.output == "" && dockerCli.Out().IsTerminal() {
    46  		return errors.New("cowardly refusing to save to a terminal. Use the -o flag or redirect")
    47  	}
    48  
    49  	if err := command.ValidateOutputPath(opts.output); err != nil {
    50  		return errors.Wrap(err, "failed to export container")
    51  	}
    52  
    53  	clnt := dockerCli.Client()
    54  
    55  	responseBody, err := clnt.ContainerExport(ctx, opts.container)
    56  	if err != nil {
    57  		return err
    58  	}
    59  	defer responseBody.Close()
    60  
    61  	if opts.output == "" {
    62  		_, err := io.Copy(dockerCli.Out(), responseBody)
    63  		return err
    64  	}
    65  
    66  	return command.CopyToFile(opts.output, responseBody)
    67  }