github.com/itscaro/cli@v0.0.0-20190705081621-c9db0fe93829/cli/command/image/pull.go (about)

     1  package image
     2  
     3  import (
     4  	"context"
     5  	"fmt"
     6  	"strings"
     7  
     8  	"github.com/docker/cli/cli"
     9  	"github.com/docker/cli/cli/command"
    10  	"github.com/docker/cli/cli/trust"
    11  	"github.com/docker/distribution/reference"
    12  	"github.com/pkg/errors"
    13  	"github.com/spf13/cobra"
    14  )
    15  
    16  // PullOptions defines what and how to pull
    17  type PullOptions struct {
    18  	remote    string
    19  	all       bool
    20  	platform  string
    21  	quiet     bool
    22  	untrusted bool
    23  }
    24  
    25  // NewPullCommand creates a new `docker pull` command
    26  func NewPullCommand(dockerCli command.Cli) *cobra.Command {
    27  	var opts PullOptions
    28  
    29  	cmd := &cobra.Command{
    30  		Use:   "pull [OPTIONS] NAME[:TAG|@DIGEST]",
    31  		Short: "Pull an image or a repository from a registry",
    32  		Args:  cli.ExactArgs(1),
    33  		RunE: func(cmd *cobra.Command, args []string) error {
    34  			opts.remote = args[0]
    35  			return RunPull(dockerCli, opts)
    36  		},
    37  	}
    38  
    39  	flags := cmd.Flags()
    40  
    41  	flags.BoolVarP(&opts.all, "all-tags", "a", false, "Download all tagged images in the repository")
    42  	flags.BoolVarP(&opts.quiet, "quiet", "q", false, "Suppress verbose output")
    43  
    44  	command.AddPlatformFlag(flags, &opts.platform)
    45  	command.AddTrustVerificationFlags(flags, &opts.untrusted, dockerCli.ContentTrustEnabled())
    46  
    47  	return cmd
    48  }
    49  
    50  // RunPull performs a pull against the engine based on the specified options
    51  func RunPull(cli command.Cli, opts PullOptions) error {
    52  	distributionRef, err := reference.ParseNormalizedNamed(opts.remote)
    53  	switch {
    54  	case err != nil:
    55  		return err
    56  	case opts.all && !reference.IsNameOnly(distributionRef):
    57  		return errors.New("tag can't be used with --all-tags/-a")
    58  	case !opts.all && reference.IsNameOnly(distributionRef):
    59  		distributionRef = reference.TagNameOnly(distributionRef)
    60  		if tagged, ok := distributionRef.(reference.Tagged); ok && !opts.quiet {
    61  			fmt.Fprintf(cli.Out(), "Using default tag: %s\n", tagged.Tag())
    62  		}
    63  	}
    64  
    65  	ctx := context.Background()
    66  	imgRefAndAuth, err := trust.GetImageReferencesAndAuth(ctx, nil, AuthResolver(cli), distributionRef.String())
    67  	if err != nil {
    68  		return err
    69  	}
    70  
    71  	// Check if reference has a digest
    72  	_, isCanonical := distributionRef.(reference.Canonical)
    73  	if !opts.untrusted && !isCanonical {
    74  		err = trustedPull(ctx, cli, imgRefAndAuth, opts)
    75  	} else {
    76  		err = imagePullPrivileged(ctx, cli, imgRefAndAuth, opts)
    77  	}
    78  	if err != nil {
    79  		if strings.Contains(err.Error(), "when fetching 'plugin'") {
    80  			return errors.New(err.Error() + " - Use `docker plugin install`")
    81  		}
    82  		return err
    83  	}
    84  	fmt.Fprintln(cli.Out(), imgRefAndAuth.Reference().String())
    85  	return nil
    86  }