containerd/cmd/ctr/fetchobject.go
Jess Valarezo a19a20303a ctr: add commands package with shared utility functions
Signed-off-by: Jess Valarezo <valarezo.jessica@gmail.com>
2017-10-23 17:40:18 -07:00

57 lines
1.2 KiB
Go

package main
import (
"io"
"os"
"github.com/containerd/containerd/cmd/ctr/commands"
"github.com/containerd/containerd/log"
"github.com/urfave/cli"
)
// TODO(stevvooe): Create "multi-fetch" mode that just takes a remote
// then receives object/hint lines on stdin, returning content as
// needed.
var fetchObjectCommand = cli.Command{
Name: "fetch-object",
Usage: "retrieve objects from a remote",
ArgsUsage: "[flags] <remote> <object> [<hint>, ...]",
Description: `Fetch objects by identifier from a remote.`,
Flags: commands.RegistryFlags,
Action: func(context *cli.Context) error {
var (
ref = context.Args().First()
)
ctx, cancel := appContext(context)
defer cancel()
resolver, err := getResolver(ctx, context)
if err != nil {
return err
}
ctx = log.WithLogger(ctx, log.G(ctx).WithField("ref", ref))
log.G(ctx).Infof("resolving")
name, desc, err := resolver.Resolve(ctx, ref)
if err != nil {
return err
}
fetcher, err := resolver.Fetcher(ctx, name)
if err != nil {
return err
}
log.G(ctx).Infof("fetching")
rc, err := fetcher.Fetch(ctx, desc)
if err != nil {
return err
}
defer rc.Close()
_, err = io.Copy(os.Stdout, rc)
return err
},
}