containerd/cmd/ctr/commands/images/pull.go
Derek McGowan a40c3830df
Add option to pull all metadata
Add flags to pull and fetch to grab all metadata.
Add fetch option to pull only metadata.

Signed-off-by: Derek McGowan <derek@mcgstyle.net>
2019-08-26 11:05:21 -07:00

127 lines
3.3 KiB
Go

/*
Copyright The containerd Authors.
Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at
http://www.apache.org/licenses/LICENSE-2.0
Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package images
import (
"fmt"
"github.com/containerd/containerd"
"github.com/containerd/containerd/cmd/ctr/commands"
"github.com/containerd/containerd/cmd/ctr/commands/content"
"github.com/containerd/containerd/images"
"github.com/containerd/containerd/log"
"github.com/containerd/containerd/platforms"
ocispec "github.com/opencontainers/image-spec/specs-go/v1"
"github.com/pkg/errors"
"github.com/urfave/cli"
)
var pullCommand = cli.Command{
Name: "pull",
Usage: "pull an image from a remote",
ArgsUsage: "[flags] <ref>",
Description: `Fetch and prepare an image for use in containerd.
After pulling an image, it should be ready to use the same reference in a run
command. As part of this process, we do the following:
1. Fetch all resources into containerd.
2. Prepare the snapshot filesystem with the pulled resources.
3. Register metadata for the image.
`,
Flags: append(append(commands.RegistryFlags, append(commands.SnapshotterFlags, commands.LabelFlag)...),
cli.StringSliceFlag{
Name: "platform",
Usage: "Pull content from a specific platform",
Value: &cli.StringSlice{},
},
cli.BoolFlag{
Name: "all-platforms",
Usage: "pull content and metadata from all platforms",
},
cli.BoolFlag{
Name: "all-metadata",
Usage: "Pull metadata for all platforms",
},
),
Action: func(context *cli.Context) error {
var (
ref = context.Args().First()
)
if ref == "" {
return fmt.Errorf("please provide an image reference to pull")
}
client, ctx, cancel, err := commands.NewClient(context)
if err != nil {
return err
}
defer cancel()
ctx, done, err := client.WithLease(ctx)
if err != nil {
return err
}
defer done(ctx)
config, err := content.NewFetchConfig(ctx, context)
if err != nil {
return err
}
img, err := content.Fetch(ctx, client, ref, config)
if err != nil {
return err
}
log.G(ctx).WithField("image", ref).Debug("unpacking")
// TODO: Show unpack status
var p []ocispec.Platform
if context.Bool("all-platforms") {
p, err = images.Platforms(ctx, client.ContentStore(), img.Target)
if err != nil {
return errors.Wrap(err, "unable to resolve image platforms")
}
} else {
for _, s := range context.StringSlice("platform") {
ps, err := platforms.Parse(s)
if err != nil {
return errors.Wrapf(err, "unable to parse platform %s", s)
}
p = append(p, ps)
}
}
if len(p) == 0 {
p = append(p, platforms.DefaultSpec())
}
for _, platform := range p {
fmt.Printf("unpacking %s %s...\n", platforms.Format(platform), img.Target.Digest)
i := containerd.NewImageWithPlatform(client, img, platforms.Only(platform))
err = i.Unpack(ctx, context.String("snapshotter"))
if err != nil {
return err
}
}
fmt.Println("done")
return nil
},
}