Merge pull request #678 from umohnani8/kpod_save

Add 'kpod save' command

README.md

@@ -47,6 +47,7 @@ It is currently in active development in the Kubernetes community through the [d
 | [kpod-pull(1)](/docs/kpod-pull.1.md)       | Pull an image from a registry |
 | [kpod-push(1)](/docs/kpod-push.1.md)       | Push an image to a specified destination |
 | [kpod-rmi(1)](/docs/kpod-rmi.1.md)         | Removes one or more images   |
+| [kpod-save(1)](/docs/kpod-save.1.md)       | Saves an image to an archive |
 | [kpod-tag(1)](/docs/kpod-tag.1.md)         | Add an additional name to a local image |
 | [kpod-version(1)](/docs/kpod-version.1.md) | Display the Kpod Version Information |
 

cmd/kpod/main.go

@@ -31,6 +31,7 @@ func main() {
 		rmiCommand,
 		tagCommand,
 		versionCommand,
+		saveCommand,
 	}
 	app.Flags = []cli.Flag{
 		cli.StringFlag{

cmd/kpod/save.go

@@ -0,0 +1,96 @@
+package main
+
+import (
+	"os"
+
+	"github.com/Sirupsen/logrus"
+	"github.com/containers/storage"
+	libkpodimage "github.com/kubernetes-incubator/cri-o/libkpod/image"
+	"github.com/pkg/errors"
+	"github.com/urfave/cli"
+)
+
+const (
+	dockerArchive = "docker-archive:"
+)
+
+type saveOptions struct {
+	output string
+	quiet  bool
+	images []string
+}
+
+var (
+	saveFlags = []cli.Flag{
+		cli.StringFlag{
+			Name:  "output, o",
+			Usage: "Write to a file, default is STDOUT",
+			Value: "/dev/stdout",
+		},
+		cli.BoolFlag{
+			Name:  "quiet, q",
+			Usage: "Suppress the output",
+		},
+	}
+	saveDescription = "Save an image to docker-archive on the local machine"
+	saveCommand     = cli.Command{
+		Name:        "save",
+		Usage:       "Save image to an archive",
+		Description: saveDescription,
+		Flags:       saveFlags,
+		Action:      saveCmd,
+		ArgsUsage:   "",
+	}
+)
+
+// saveCmd saves the image to either docker-archive or oci
+func saveCmd(c *cli.Context) error {
+	args := c.Args()
+	if len(args) == 0 {
+		return errors.Errorf("need at least 1 argument")
+	}
+
+	store, err := getStore(c)
+	if err != nil {
+		return err
+	}
+
+	output := c.String("output")
+	quiet := c.Bool("quiet")
+
+	if output == "/dev/stdout" {
+		fi := os.Stdout
+		if logrus.IsTerminal(fi) {
+			return errors.Errorf("refusing to save to terminal. Use -o flag or redirect")
+		}
+	}
+
+	opts := saveOptions{
+		output: output,
+		quiet:  quiet,
+		images: args,
+	}
+
+	return saveImage(store, opts)
+}
+
+// saveImage pushes the image to docker-archive or oci by
+// calling pushImageForSave
+func saveImage(store storage.Store, opts saveOptions) error {
+	dst := dockerArchive + opts.output
+
+	pushOpts := libkpodimage.CopyOptions{
+		SignaturePolicyPath: "",
+		Store:               store,
+	}
+
+	// only one image is supported for now
+	// future pull requests will fix this
+	for _, image := range opts.images {
+		dest := dst + ":" + image
+		if err := libkpodimage.PushImage(image, dest, pushOpts); err != nil {
+			return errors.Wrapf(err, "unable to save %q", image)
+		}
+	}
+	return nil
+}

completions/bash/kpod

@@ -130,6 +130,16 @@ _kpod_version() {
      _complete_ "$options_with_args" "$boolean_options"
 }
 
+_kpod_save() {
+     local options_with_args="
+     --output -o
+     "
+     local boolean_options="
+     --quiet -q
+     "
+     _complete_ "$options_with_args" "$boolean_options"
+}
+
 _complete_() {
     local options_with_args=$1
     local boolean_options="$2 -h --help"

docs/kpod-save.1.md

@@ -0,0 +1,51 @@
+% kpod(1) kpod-save - Simple tool to save an image to an archive
+% Urvashi Mohnani
+# kpod-save "1" "July 2017" "kpod"
+
+## NAME
+kpod-save - save an image to docker-archive or oci
+
+## SYNOPSIS
+**kpod save**
+**NAME[:TAG]**
+[**--help**|**-h**]
+
+## DESCRIPTION
+**kpod save** saves an image to either **docker-archive** on the loacl machine.
+**kpod save** writes to STDOUT by default and can be redirected to a file
+using the **output** flag. The **quiet** flag suppresses the output when set.
+
+**kpod [GLOBAL OPTIONS]**
+
+**kpod save [GLOBAL OPTIONS]**
+
+**kpod save [OPTIONS] NAME[:TAG] [GLOBAL OPTIONS]**
+
+## OPTIONS
+
+**--output, -o**
+Write to a file, default is STDOUT
+
+**--quiet, -q**
+Suppress the output
+
+## GLOBAL OPTIONS
+
+**--help, -h**
+  Print usage statement
+
+## EXAMPLES
+
+```
+# kpod save --quiet -o alpine.tar alpine:2.6
+```
+
+```
+# kpod save > alpine-all.tar alpine
+```
+
+## SEE ALSO
+kpod(1), kpod-load(1), crio(8), crio.conf(5)
+
+## HISTORY
+July 2017, Originally compiled by Urvashi Mohnani <umohnani@redhat.com>

test/kpod.bats

@@ -115,6 +115,7 @@ function teardown() {
 
 @test "kpod history json flag" {
 	run ${KPOD_BINARY} ${KPOD_OPTIONS} pull $IMAGE
+	[ "$status" -eq 0 ]
 	run bash -c "${KPOD_BINARY} ${KPOD_OPTIONS} history --json $IMAGE | python -m json.tool"
 	echo "$output"
 	[ "$status" -eq 0 ]

test/kpod_save.bats

@@ -0,0 +1,54 @@
+#!/usr/bin/env bats
+
+load helpers
+
+IMAGE="alpine:latest"
+ROOT="$TESTDIR/crio"
+RUNROOT="$TESTDIR/crio-run"
+KPOD_OPTIONS="--root $ROOT --runroot $RUNROOT --storage-driver vfs"
+
+function teardown() {
+    cleanup_test
+}
+
+@test "kpod save output flag" {
+	run ${KPOD_BINARY} ${KPOD_OPTIONS} pull $IMAGE
+	[ "$status" -eq 0 ]
+	run ${KPOD_BINARY} ${KPOD_OPTIONS} save -o alpine.tar $IMAGE
+	echo "$output"
+	[ "$status" -eq 0 ]
+	run ${KPOD_BINARY} ${KPOD_OPTIONS} rmi $IMAGE
+	[ "$status" -eq 0 ]
+	rm -f alpine.tar
+	[ "$status" -eq 0 ]
+}
+
+@test "kpod save using stdout" {
+	run ${KPOD_BINARY} ${KPOD_OPTIONS} pull $IMAGE
+	[ "$status" -eq 0 ]
+	run ${KPOD_BINARY} ${KPOD_OPTIONS} save > alpine.tar $IMAGE
+	echo "$output"
+	[ "$status" -eq 0 ]
+	run ${KPOD_BINARY} ${KPOD_OPTIONS} rmi $IMAGE
+	[ "$status" -eq 0 ]
+	rm -f alpine.tar
+	[ "$status" -eq 0 ]
+}
+
+@test "kpod save quiet flag" {
+	run ${KPOD_BINARY} ${KPOD_OPTIONS} pull $IMAGE
+	[ "$status" -eq 0 ]
+	run ${KPOD_BINARY} ${KPOD_OPTIONS} save -q -o alpine.tar $IMAGE
+	echo "$output"
+	[ "$status" -eq 0 ]
+	run ${KPOD_BINARY} ${KPOD_OPTIONS} rmi $IMAGE
+	[ "$status" -eq 0 ]
+	rm -f alpine.tar
+	[ "$status" -eq 0 ]
+}
+
+@test "kpod save non-existent image" {
+	run ${KPOD_BINARY} ${KPOD_OPTIONS} save -o alpine.tar $IMAGE
+	echo "$output"
+	[ "$status" -ne 0 ]
+}