github.com/sld880311/docker@v0.0.0-20200524143708-d5593973a475/cli/command/container/export.go (about)

     1  package container
     2  
     3  import (
     4  	"errors"
     5  	"io"
     6  
     7  	"golang.org/x/net/context"
     8  
     9  	"github.com/docker/docker/cli"
    10  	"github.com/docker/docker/cli/command"
    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.DockerCli) *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(dockerCli, opts)
    30  		},
    31  	}
    32  
    33  	flags := cmd.Flags()
    34  
    35  	flags.StringVarP(&opts.output, "output", "o", "", "Write to a file, instead of STDOUT")
    36  
    37  	return cmd
    38  }
    39  
    40  func runExport(dockerCli *command.DockerCli, opts exportOptions) error {
    41  	if opts.output == "" && dockerCli.Out().IsTerminal() {
    42  		return errors.New("Cowardly refusing to save to a terminal. Use the -o flag or redirect.")
    43  	}
    44  
    45  	clnt := dockerCli.Client()
    46  
    47  	responseBody, err := clnt.ContainerExport(context.Background(), opts.container)
    48  	if err != nil {
    49  		return err
    50  	}
    51  	defer responseBody.Close()
    52  
    53  	if opts.output == "" {
    54  		_, err := io.Copy(dockerCli.Out(), responseBody)
    55  		return err
    56  	}
    57  
    58  	return command.CopyToFile(opts.output, responseBody)
    59  }