libkpod/image/copy.go: Add pull by short-name

If the user provides kpod pull a short name like 'debian', we
still want the pull to be sucessful.  As such, when a short
name is provided, we get the list of searchable registries via
the systemregistries code in containers-storage.  We then
append a tag of 'latest' (if not provided) and we formulate
a list of possible fully-qualified image names to try.

Vendor update for containers-storage to bring in the system_registries
code.

Also includes a patch from Nalin to fix compilation errors.

Signed-off-by: baude <bbaude@redhat.com>

cmd/kpod/pull.go

@@ -3,6 +3,11 @@ package main
 import (
 	"os"
 
+	"fmt"
+	"github.com/containers/image/docker/reference"
+	"github.com/containers/image/pkg/sysregistries"
+	"github.com/containers/image/transports/alltransports"
+	"github.com/containers/image/types"
 	"github.com/pkg/errors"
 	"github.com/sirupsen/logrus"
 	"github.com/urfave/cli"
@@ -31,9 +36,84 @@ var (
 	}
 )
 
+// struct for when a user passes a short or incomplete
+// image name
+type imagePullStruct struct {
+	imageName   string
+	tag         string
+	registry    string
+	hasRegistry bool
+	transport   string
+}
+
+func (ips imagePullStruct) returnFQName() string {
+	return fmt.Sprintf("%s%s/%s:%s", ips.transport, ips.registry, ips.imageName, ips.tag)
+}
+
+func getRegistriesToTry(image string) ([]string, error) {
+	var registries []string
+	var imageError = fmt.Sprintf("unable to parse '%s'\n", image)
+	imgRef, err := reference.Parse(image)
+	if err != nil {
+		return nil, errors.Wrapf(err, imageError)
+	}
+	tagged, isTagged := imgRef.(reference.NamedTagged)
+	tag := "latest"
+	if isTagged {
+		tag = tagged.Tag()
+	}
+	hasDomain := true
+	registry := reference.Domain(imgRef.(reference.Named))
+	if registry == "" {
+		hasDomain = false
+	}
+	imageName := reference.Path(imgRef.(reference.Named))
+	pImage := imagePullStruct{
+		imageName,
+		tag,
+		registry,
+		hasDomain,
+		"docker://",
+	}
+	if pImage.hasRegistry {
+		// If input has a registry, we have to assume they included an image
+		// name but maybe not a tag
+		pullRef, err := alltransports.ParseImageName(pImage.returnFQName())
+		if err != nil {
+			return nil, errors.Errorf(imageError)
+		}
+		registries = append(registries, pullRef.DockerReference().String())
+	} else {
+		// No registry means we check the globals registries configuration file
+		// and assemble a list of candidate sources to try
+		registryConfigPath := ""
+		envOverride := os.Getenv("REGISTRIES_CONFIG_PATH")
+		if len(envOverride) > 0 {
+			registryConfigPath = envOverride
+		}
+		searchRegistries, err := sysregistries.GetRegistries(&types.SystemContext{SystemRegistriesConfPath: registryConfigPath})
+		if err != nil {
+			fmt.Println(err)
+			return nil, errors.Errorf("unable to parse the registries.conf file and"+
+				" the image name '%s' is incomplete.", imageName)
+		}
+		for _, searchRegistry := range searchRegistries {
+			pImage.registry = searchRegistry
+			pullRef, err := alltransports.ParseImageName(pImage.returnFQName())
+			if err != nil {
+				return nil, errors.Errorf("unable to parse '%s'", pImage.returnFQName())
+			}
+			registries = append(registries, pullRef.DockerReference().String())
+		}
+	}
+	return registries, nil
+}
+
 // pullCmd gets the data from the command line and calls pullImage
 // to copy an image from a registry to a local machine
 func pullCmd(c *cli.Context) error {
+	var fqRegistries []string
+
 	args := c.Args()
 	if len(args) == 0 {
 		logrus.Errorf("an image name must be specified")
@@ -44,13 +124,28 @@ func pullCmd(c *cli.Context) error {
 		return nil
 	}
 	image := args[0]
-
+	srcRef, err := alltransports.ParseImageName(image)
+	if err != nil {
+		fqRegistries, err = getRegistriesToTry(image)
+		if err != nil {
+			fmt.Println(err)
+		}
+	} else {
+		fqRegistries = append(fqRegistries, srcRef.DockerReference().String())
+	}
 	runtime, err := getRuntime(c)
+	defer runtime.Shutdown(false)
+
 	if err != nil {
 		return errors.Wrapf(err, "could not create runtime")
 	}
-	if err := runtime.PullImage(image, c.Bool("all-tags"), os.Stdout); err != nil {
+	for _, fqname := range fqRegistries {
-		return errors.Errorf("error pulling image from %q: %v", image, err)
+		fmt.Printf("Trying to pull %s...", fqname)
+		if err := runtime.PullImage(fqname, c.Bool("all-tags"), os.Stdout); err != nil {
+			fmt.Printf(" Failed\n")
+		} else {
+			return nil
+		}
 	}
-	return nil
+	return errors.Errorf("error pulling image from %q", image)
 }

libpod/image.go

@@ -121,7 +121,7 @@ func (r *Runtime) PullImage(imgName string, allTags bool, reportWriter io.Writer
 	copyOptions := common.GetCopyOptions(reportWriter, "", nil, nil, common.SigningOptions{})
 
 	for _, image := range images {
-		destRef, err := is.Transport.ParseStoreReference(r.store, image)
+		destRef, err := is.Transport.ParseStoreReference(r.store, srcRef.DockerReference().String())
 		if err != nil {
 			return errors.Errorf("error parsing dest reference name: %v", err)
 		}

libpod/images/copy_ref.go

@@ -66,26 +66,12 @@ func (c *CopyRef) NewImage(sc *types.SystemContext) (types.Image, error) {
 	return image.FromSource(src)
 }
 
-func selectManifestType(preferred string, acceptable, supported []string) string {
-	selected := preferred
-	for _, accept := range acceptable {
-		if preferred == accept {
-			return preferred
-		}
-		for _, support := range supported {
-			if accept == support {
-				selected = accept
-			}
-		}
-	}
-	return selected
-}
-
 // NewImageSource creates a new image source from the given system context and manifest
 func (c *CopyRef) NewImageSource(sc *types.SystemContext) (src types.ImageSource, err error) {
 	// Decide which type of manifest and configuration output we're going to provide.
-	manifestType := selectManifestType(c.preferredManifestType, nil, nil)
+	manifestType := c.preferredManifestType
 	// If it's not a format we support, return an error.
+	// Try to provide a manifest and configuration in the same format the current ones are in.
 	if manifestType != v1.MediaTypeImageManifest && manifestType != docker.V2S2MediaTypeManifest {
 		return nil, errors.Errorf("no supported manifest types (attempted to use %q, only know %q and %q)",
 			manifestType, v1.MediaTypeImageManifest, docker.V2S2MediaTypeManifest)

test/helpers.bash

@@ -59,6 +59,9 @@ PIDS_LIMIT=${PIDS_LIMIT:-1024}
 
 TESTDIR=$(mktemp -d)
 
+# kpod pull needs a configuration file for shortname pulls
+export REGISTRIES_CONFIG_PATH="$INTEGRATION_ROOT/registries.conf"
+
 # Setup default hooks dir
 HOOKSDIR=$TESTDIR/hooks
 mkdir ${HOOKSDIR}

test/kpod.bats

@@ -17,52 +17,6 @@ function teardown() {
 	[ "$status" -eq 0 ]
 }
 
-@test "kpod pull from docker with tag" {
-	run ${KPOD_BINARY} ${KPOD_OPTIONS} pull debian:6.0.10
-	echo "$output"
-	[ "$status" -eq 0 ]
-	run ${KPOD_BINARY} $KPOD_OPTIONS rmi debian:6.0.10
-	[ "$status" -eq 0 ]
-}
-
-@test "kpod pull from docker without tag" {
-	run ${KPOD_BINARY} $KPOD_OPTIONS pull debian
-	echo "$output"
-	[ "$status" -eq 0 ]
-	run ${KPOD_BINARY} $KPOD_OPTIONS rmi debian
-	[ "$status" -eq 0 ]
-}
-
-@test "kpod pull from a non-docker registry with tag" {
-	run ${KPOD_BINARY} $KPOD_OPTIONS pull registry.fedoraproject.org/fedora:rawhide
-	echo "$output"
-	[ "$status" -eq 0 ]
-	run ${KPOD_BINARY} $KPOD_OPTIONS rmi registry.fedoraproject.org/fedora:rawhide
-	[ "$status" -eq 0 ]
-}
-
-@test "kpod pull from a non-docker registry without tag" {
-	run ${KPOD_BINARY} $KPOD_OPTIONS pull registry.fedoraproject.org/fedora
-	echo "$output"
-	[ "$status" -eq 0 ]
-	run ${KPOD_BINARY} $KPOD_OPTIONS rmi registry.fedoraproject.org/fedora
-	[ "$status" -eq 0 ]
-}
-
-@test "kpod pull using digest" {
-	run ${KPOD_BINARY} $KPOD_OPTIONS pull alpine@sha256:1072e499f3f655a032e88542330cf75b02e7bdf673278f701d7ba61629ee3ebe
-	echo "$output"
-	[ "$status" -eq 0 ]
-	run ${KPOD_BINARY} $KPOD_OPTIONS rmi alpine:latest
-	[ "$status" -eq 0 ]
-}
-
-@test "kpod pull from a non existent image" {
-	run ${KPOD_BINARY} $KPOD_OPTIONS pull umohnani/get-started
-	echo "$output"
-	[ "$status" -ne 0 ]
-}
-
 @test "kpod history default" {
 	run ${KPOD_BINARY} ${KPOD_OPTIONS} pull $IMAGE
 	[ "$status" -eq 0 ]

test/kpod_pull.bats

@@ -0,0 +1,74 @@
+#!/usr/bin/env bats
+
+load helpers
+
+IMAGE="alpine:latest"
+ROOT="$TESTDIR/crio"
+RUNROOT="$TESTDIR/crio-run"
+KPOD_OPTIONS="--root $ROOT --runroot $RUNROOT ${STORAGE_OPTS}"
+
+function teardown() {
+  cleanup_test
+}
+
+@test "kpod pull from docker with tag" {
+	run ${KPOD_BINARY} ${KPOD_OPTIONS} pull debian:6.0.10
+	echo "$output"
+	[ "$status" -eq 0 ]
+	run ${KPOD_BINARY} $KPOD_OPTIONS rmi debian:6.0.10
+	[ "$status" -eq 0 ]
+}
+
+@test "kpod pull from docker without tag" {
+	run ${KPOD_BINARY} $KPOD_OPTIONS pull debian
+	echo "$output"
+	[ "$status" -eq 0 ]
+	run ${KPOD_BINARY} $KPOD_OPTIONS rmi debian
+	[ "$status" -eq 0 ]
+}
+
+@test "kpod pull from a non-docker registry with tag" {
+	run ${KPOD_BINARY} $KPOD_OPTIONS pull registry.fedoraproject.org/fedora:rawhide
+	echo "$output"
+	[ "$status" -eq 0 ]
+	run ${KPOD_BINARY} $KPOD_OPTIONS rmi registry.fedoraproject.org/fedora:rawhide
+	[ "$status" -eq 0 ]
+}
+
+@test "kpod pull from a non-docker registry without tag" {
+	run ${KPOD_BINARY} $KPOD_OPTIONS pull registry.fedoraproject.org/fedora
+	echo "$output"
+	[ "$status" -eq 0 ]
+	run ${KPOD_BINARY} $KPOD_OPTIONS rmi registry.fedoraproject.org/fedora
+	[ "$status" -eq 0 ]
+}
+
+@test "kpod pull using digest" {
+	run ${KPOD_BINARY} $KPOD_OPTIONS pull alpine@sha256:1072e499f3f655a032e88542330cf75b02e7bdf673278f701d7ba61629ee3ebe
+	echo "$output"
+	[ "$status" -eq 0 ]
+	run ${KPOD_BINARY} $KPOD_OPTIONS rmi alpine:latest
+	[ "$status" -eq 0 ]
+}
+
+@test "kpod pull from a non existent image" {
+	run ${KPOD_BINARY} $KPOD_OPTIONS pull umohnani/get-started
+	echo "$output"
+	[ "$status" -ne 0 ]
+}
+
+@test "kpod pull from docker with shortname" {
+	run ${KPOD_BINARY} ${KPOD_OPTIONS} pull debian
+	echo "$output"
+	[ "$status" -eq 0 ]
+	run ${KPOD_BINARY} $KPOD_OPTIONS rmi docker.io/debian:latest
+	[ "$status" -eq 0 ]
+}
+
+@test "kpod pull from docker with shortname and tag" {
+	run ${KPOD_BINARY} ${KPOD_OPTIONS} pull debian:6.0.10
+	echo "$output"
+	[ "$status" -eq 0 ]
+	run ${KPOD_BINARY} $KPOD_OPTIONS rmi docker.io/debian:6.0.10
+	[ "$status" -eq 0 ]
+}

test/registries.conf

@@ -0,0 +1,9 @@
+[registries.search]
+registries = ['registry.access.redhat.com', 'registry.fedoraproject.org', 'docker.io']
+
+[registries.insecure]
+registries = []
+
+#blocked (docker only)
+[registries.block]
+registries = []

vendor/github.com/containers/image/pkg/sysregistries/system_registries.go

@@ -0,0 +1,86 @@
+package sysregistries
+
+import (
+	"github.com/BurntSushi/toml"
+	"github.com/containers/image/types"
+	"io/ioutil"
+	"path/filepath"
+)
+
+// systemRegistriesConfPath is the path to the system-wide registry configuration file
+// and is used to add/subtract potential registries for obtaining images.
+// You can override this at build time with
+// -ldflags '-X github.com/containers/image/sysregistries.systemRegistriesConfPath=$your_path'
+var systemRegistriesConfPath = builtinRegistriesConfPath
+
+// builtinRegistriesConfPath is the path to registry configuration file
+// DO NOT change this, instead see systemRegistriesConfPath above.
+const builtinRegistriesConfPath = "/etc/containers/registries.conf"
+
+type registries struct {
+	Registries []string `toml:"registries"`
+}
+
+type tomlConfig struct {
+	Registries struct {
+		Search   registries `toml:"search"`
+		Insecure registries `toml:"insecure"`
+		Block    registries `toml:"block"`
+	} `toml:"registries"`
+}
+
+// Reads the global registry file from the filesystem. Returns
+// a byte array
+func readRegistryConf(ctx *types.SystemContext) ([]byte, error) {
+	dirPath := systemRegistriesConfPath
+	if ctx != nil {
+		if ctx.SystemRegistriesConfPath != "" {
+			dirPath = ctx.SystemRegistriesConfPath
+		} else if ctx.RootForImplicitAbsolutePaths != "" {
+			dirPath = filepath.Join(ctx.RootForImplicitAbsolutePaths, systemRegistriesConfPath)
+		}
+	}
+	configBytes, err := ioutil.ReadFile(dirPath)
+	return configBytes, err
+}
+
+// For mocking in unittests
+var readConf = readRegistryConf
+
+// Loads the registry configuration file from the filesystem and
+// then unmarshals it.  Returns the unmarshalled object.
+func loadRegistryConf(ctx *types.SystemContext) (*tomlConfig, error) {
+	config := &tomlConfig{}
+
+	configBytes, err := readConf(ctx)
+	if err != nil {
+		return nil, err
+	}
+
+	err = toml.Unmarshal(configBytes, &config)
+	return config, err
+}
+
+// GetRegistries returns an array of strings that contain the names
+// of the registries as defined in the system-wide
+// registries file.  it returns an empty array if none are
+// defined
+func GetRegistries(ctx *types.SystemContext) ([]string, error) {
+	config, err := loadRegistryConf(ctx)
+	if err != nil {
+		return nil, err
+	}
+	return config.Registries.Search.Registries, nil
+}
+
+// GetInsecureRegistries returns an array of strings that contain the names
+// of the insecure registries as defined in the system-wide
+// registries file.  it returns an empty array if none are
+// defined
+func GetInsecureRegistries(ctx *types.SystemContext) ([]string, error) {
+	config, err := loadRegistryConf(ctx)
+	if err != nil {
+		return nil, err
+	}
+	return config.Registries.Insecure.Registries, nil
+}