DockerCLI/cli/command/container/export.go

65 lines
1.5 KiB
Go

package container
import (
"context"
"io"
"github.com/docker/cli/cli"
"github.com/docker/cli/cli/command"
"github.com/docker/cli/cli/command/completion"
"github.com/pkg/errors"
"github.com/spf13/cobra"
)
type exportOptions struct {
container string
output string
}
// NewExportCommand creates a new `docker export` command
func NewExportCommand(dockerCli command.Cli) *cobra.Command {
var opts exportOptions
cmd := &cobra.Command{
Use: "export [OPTIONS] CONTAINER",
Short: "Export a container's filesystem as a tar archive",
Args: cli.ExactArgs(1),
RunE: func(cmd *cobra.Command, args []string) error {
opts.container = args[0]
return runExport(dockerCli, opts)
},
ValidArgsFunction: completion.ContainerNames(dockerCli, true),
}
flags := cmd.Flags()
flags.StringVarP(&opts.output, "output", "o", "", "Write to a file, instead of STDOUT")
return cmd
}
func runExport(dockerCli command.Cli, opts exportOptions) error {
if opts.output == "" && dockerCli.Out().IsTerminal() {
return errors.New("cowardly refusing to save to a terminal. Use the -o flag or redirect")
}
if err := command.ValidateOutputPath(opts.output); err != nil {
return errors.Wrap(err, "failed to export container")
}
clnt := dockerCli.Client()
responseBody, err := clnt.ContainerExport(context.Background(), opts.container)
if err != nil {
return err
}
defer responseBody.Close()
if opts.output == "" {
_, err := io.Copy(dockerCli.Out(), responseBody)
return err
}
return command.CopyToFile(opts.output, responseBody)
}