LCOW: pull goes to correct stores

Signed-off-by: John Howard <jhoward@microsoft.com>

api/server/router/image/backend.go

@@ -40,7 +40,7 @@ type importExportBackend interface {
 }
 
 type registryBackend interface {
-	PullImage(ctx context.Context, image, tag string, metaHeaders map[string][]string, authConfig *types.AuthConfig, outStream io.Writer) error
+	PullImage(ctx context.Context, image, tag, platform string, metaHeaders map[string][]string, authConfig *types.AuthConfig, outStream io.Writer) error
 	PushImage(ctx context.Context, image, tag string, metaHeaders map[string][]string, authConfig *types.AuthConfig, outStream io.Writer) error
 	SearchRegistryForImages(ctx context.Context, filtersArgs string, term string, limit int, authConfig *types.AuthConfig, metaHeaders map[string][]string) (*registry.SearchResults, error)
 }

api/server/router/image/image_routes.go

@@ -6,6 +6,7 @@ import (
 	"fmt"
 	"io"
 	"net/http"
+	"runtime"
 	"strconv"
 	"strings"
 
@@ -17,6 +18,7 @@ import (
 	"github.com/docker/docker/api/types/versions"
 	"github.com/docker/docker/pkg/ioutils"
 	"github.com/docker/docker/pkg/streamformatter"
+	"github.com/docker/docker/pkg/system"
 	"github.com/docker/docker/registry"
 	"golang.org/x/net/context"
 )
@@ -85,6 +87,41 @@ func (s *imageRouter) postImagesCreate(ctx context.Context, w http.ResponseWrite
 	)
 	defer output.Close()
 
+	// TODO @jhowardmsft LCOW Support: Eventually we will need an API change
+	// so that platform comes from (for example) r.Form.Get("platform"). For
+	// the initial implementation, we assume that the platform is the
+	// runtime OS of the host. It will also need a validation function such
+	// as below which should be called after getting it from the API.
+	//
+	// Ensures the requested platform is valid and normalized
+	//func validatePlatform(req string) (string, error) {
+	//	req = strings.ToLower(req)
+	//	if req == "" {
+	//		req = runtime.GOOS // default to host platform
+	//	}
+	//	valid := []string{runtime.GOOS}
+	//
+	//	if runtime.GOOS == "windows" && system.LCOWSupported() {
+	//		valid = append(valid, "linux")
+	//	}
+	//
+	//	for _, item := range valid {
+	//		if req == item {
+	//			return req, nil
+	//		}
+	//	}
+	//	return "", fmt.Errorf("invalid platform requested: %s", req)
+	//}
+	//
+	// And in the call-site:
+	//	if platform, err = validatePlatform(platform); err != nil {
+	//		return err
+	//	}
+	platform := runtime.GOOS
+	if platform == "windows" && system.LCOWSupported() {
+		platform = "linux"
+	}
+
 	w.Header().Set("Content-Type", "application/json")
 
 	if image != "" { //pull
@@ -106,12 +143,13 @@ func (s *imageRouter) postImagesCreate(ctx context.Context, w http.ResponseWrite
 			}
 		}
 
-		err = s.backend.PullImage(ctx, image, tag, metaHeaders, authConfig, output)
+		err = s.backend.PullImage(ctx, image, tag, platform, metaHeaders, authConfig, output)
 	} else { //import
 		src := r.Form.Get("fromSrc")
 		// 'err' MUST NOT be defined within this block, we need any error
 		// generated from the download to be available to the output
 		// stream processing below
+		// TODO @jhowardmsft LCOW Support: This will need extending for the platform too.
 		err = s.backend.ImportImage(src, repo, tag, message, r.Body, output, r.Form["changes"])
 	}
 	if err != nil {

daemon/build.go

@@ -129,7 +129,12 @@ func (daemon *Daemon) pullForBuilder(ctx context.Context, name string, authConfi
 		pullRegistryAuth = &resolvedConfig
 	}
 
-	if err := daemon.pullImageWithReference(ctx, ref, nil, pullRegistryAuth, output); err != nil {
+	// TODO @jhowardmsft LCOW Support: For now, use the runtime operating system of the host.
+	// When it gets to the builder part, this will need revisiting. There would have to be
+	// some indication from the user either through CLI flag to build, or through an explicit
+	// mechanism in a dockerfile such as a parser directive extension or an addition to
+	// the FROM statement syntax.
+	if err := daemon.pullImageWithReference(ctx, ref, runtime.GOOS, nil, pullRegistryAuth, output); err != nil {
 		return nil, err
 	}
 	return daemon.GetImage(name)

daemon/cluster/executor/backend.go

@@ -30,7 +30,7 @@ type Backend interface {
 	FindNetwork(idName string) (libnetwork.Network, error)
 	SetupIngress(clustertypes.NetworkCreateRequest, string) (<-chan struct{}, error)
 	ReleaseIngress() (<-chan struct{}, error)
-	PullImage(ctx context.Context, image, tag string, metaHeaders map[string][]string, authConfig *types.AuthConfig, outStream io.Writer) error
+	PullImage(ctx context.Context, image, tag, platform string, metaHeaders map[string][]string, authConfig *types.AuthConfig, outStream io.Writer) error
 	CreateManagedContainer(config types.ContainerCreateConfig) (container.ContainerCreateCreatedBody, error)
 	ContainerStart(name string, hostConfig *container.HostConfig, checkpoint string, checkpointDir string) error
 	ContainerStop(name string, seconds *int) error

daemon/cluster/executor/container/adapter.go

@@ -7,6 +7,7 @@ import (
 	"fmt"
 	"io"
 	"os"
+	"runtime"
 	"strings"
 	"syscall"
 	"time"
@@ -20,6 +21,7 @@ import (
 	containerpkg "github.com/docker/docker/container"
 	"github.com/docker/docker/daemon/cluster/convert"
 	executorpkg "github.com/docker/docker/daemon/cluster/executor"
+	"github.com/docker/docker/pkg/system"
 	"github.com/docker/libnetwork"
 	"github.com/docker/swarmkit/agent/exec"
 	"github.com/docker/swarmkit/api"
@@ -88,7 +90,13 @@ func (c *containerAdapter) pullImage(ctx context.Context) error {
 	pr, pw := io.Pipe()
 	metaHeaders := map[string][]string{}
 	go func() {
-		err := c.backend.PullImage(ctx, c.container.image(), "", metaHeaders, authConfig, pw)
+		// TODO @jhowardmsft LCOW Support: This will need revisiting as
+		// the stack is built up to include LCOW support for swarm.
+		platform := runtime.GOOS
+		if platform == "windows" && system.LCOWSupported() {
+			platform = "linux"
+		}
+		err := c.backend.PullImage(ctx, c.container.image(), "", platform, metaHeaders, authConfig, pw)
 		pw.CloseWithError(err)
 	}()
 

daemon/image_pull.go

@@ -18,7 +18,7 @@ import (
 
 // PullImage initiates a pull operation. image is the repository name to pull, and
 // tag may be either empty, or indicate a specific tag to pull.
-func (daemon *Daemon) PullImage(ctx context.Context, image, tag string, metaHeaders map[string][]string, authConfig *types.AuthConfig, outStream io.Writer) error {
+func (daemon *Daemon) PullImage(ctx context.Context, image, tag, platform string, metaHeaders map[string][]string, authConfig *types.AuthConfig, outStream io.Writer) error {
 	// Special case: "pull -a" may send an image name with a
 	// trailing :. This is ugly, but let's not break API
 	// compatibility.
@@ -43,10 +43,10 @@ func (daemon *Daemon) PullImage(ctx context.Context, image, tag string, metaHead
 		}
 	}
 
-	return daemon.pullImageWithReference(ctx, ref, metaHeaders, authConfig, outStream)
+	return daemon.pullImageWithReference(ctx, ref, platform, metaHeaders, authConfig, outStream)
 }
 
-func (daemon *Daemon) pullImageWithReference(ctx context.Context, ref reference.Named, metaHeaders map[string][]string, authConfig *types.AuthConfig, outStream io.Writer) error {
+func (daemon *Daemon) pullImageWithReference(ctx context.Context, ref reference.Named, platform string, metaHeaders map[string][]string, authConfig *types.AuthConfig, outStream io.Writer) error {
 	// Include a buffer so that slow client connections don't affect
 	// transfer performance.
 	progressChan := make(chan progress.Progress, 100)
@@ -60,11 +60,10 @@ func (daemon *Daemon) pullImageWithReference(ctx context.Context, ref reference.
 		close(writesDone)
 	}()
 
-	// ------------------------------------------------------------------------------
-	// TODO @jhowardmsft LCOW. For now, use just the store for the host OS. This will
-	// need some work to complete - we won't know the platform until after metadata
-	// is pulled from the repository. This affects plugin as well to complete.
-	// ------------------------------------------------------------------------------
+	// Default to the host OS platform in case it hasn't been populated with an explicit value.
+	if platform == "" {
+		platform = runtime.GOOS
+	}
 
 	imagePullConfig := &distribution.ImagePullConfig{
 		Config: distribution.Config{
@@ -73,12 +72,13 @@ func (daemon *Daemon) pullImageWithReference(ctx context.Context, ref reference.
 			ProgressOutput:   progress.ChanOutput(progressChan),
 			RegistryService:  daemon.RegistryService,
 			ImageEventLogger: daemon.LogImageEvent,
-			MetadataStore:    daemon.stores[runtime.GOOS].distributionMetadataStore,
-			ImageStore:       distribution.NewImageConfigStoreFromStore(daemon.stores[runtime.GOOS].imageStore),
-			ReferenceStore:   daemon.stores[runtime.GOOS].referenceStore,
+			MetadataStore:    daemon.stores[platform].distributionMetadataStore,
+			ImageStore:       distribution.NewImageConfigStoreFromStore(daemon.stores[platform].imageStore),
+			ReferenceStore:   daemon.stores[platform].referenceStore,
 		},
 		DownloadManager: daemon.downloadManager,
 		Schema2Types:    distribution.ImageTypes,
+		Platform:        platform,
 	}
 
 	err := distribution.Pull(ctx, ref, imagePullConfig)

distribution/config.go

@@ -59,6 +59,9 @@ type ImagePullConfig struct {
 	// Schema2Types is the valid schema2 configuration types allowed
 	// by the pull operation.
 	Schema2Types []string
+	// Platform is the requested platform of the image being pulled to ensure it can be validated
+	// when the host platform supports multiple image operating systems.
+	Platform string
 }
 
 // ImagePushConfig stores push configuration.