Porter triggers autobuild when detecting that invocation image does n…

…ot exist (getporter#1828)

* Porter triggers autobuild when detecting that invocation image does not exist

Signed-off-by: joshuabezaleel <joshua.bezaleel@gmail.com>

* 1. Change function name from IsInvocationImagExists to IsImageCached along with some explanation comment.
2. Use invocationImage directly as an input to list images
3. Wrap error from Docker SDK and remove error wrap on stamp.go
4. Fix wording to "local image cache" from "host registry"

Signed-off-by: joshuabezaleel <joshua.bezaleel@gmail.com>

pkg/cnab/cnab-to-oci/helpers.go

@@ -11,6 +11,7 @@ type TestRegistry struct {
 	MockPullBundle          func(ref cnab.OCIReference, insecureRegistry bool) (cnab.BundleReference, error)
 	MockPushBundle          func(bundleRef cnab.BundleReference, insecureRegistry bool) (bundleReference cnab.BundleReference, err error)
 	MockPushInvocationImage func(invocationImage string) (imageDigest digest.Digest, err error)
+	MockIsImageCached       func(invocationImage string) (bool, error)
 }
 
 func NewTestRegistry() *TestRegistry {
@@ -39,3 +40,11 @@ func (t TestRegistry) PushInvocationImage(invocationImage string) (digest.Digest
 	}
 	return "", nil
 }
+
+func (t TestRegistry) IsImageCached(invocationImage string) (bool, error) {
+	if t.MockIsImageCached != nil {
+		return t.MockIsImageCached(invocationImage)
+	}
+
+	return true, nil
+}

pkg/cnab/cnab-to-oci/provider.go

@@ -17,4 +17,7 @@ type RegistryProvider interface {
 	// the expected format of the invocationImage is REGISTRY/NAME:TAG.
 	// Returns the image digest from the registry.
 	PushInvocationImage(invocationImage string) (digest.Digest, error)
+
+	// IsImageCached checks whether a particular invocation image exists in the local image cache.
+	IsImageCached(invocationImage string) (bool, error)
 }

pkg/cnab/cnab-to-oci/registry.go

@@ -14,6 +14,7 @@ import (
 	dockerconfig "github.com/docker/cli/cli/config"
 	cliflags "github.com/docker/cli/cli/flags"
 	"github.com/docker/docker/api/types"
+	"github.com/docker/docker/api/types/filters"
 	"github.com/docker/docker/pkg/jsonmessage"
 	"github.com/docker/docker/pkg/term"
 	"github.com/opencontainers/go-digest"
@@ -193,3 +194,25 @@ func (r *Registry) getDockerClient() (*command.DockerCli, error) {
 	}
 	return cli, nil
 }
+
+func (r *Registry) IsImageCached(invocationImage string) (bool, error) {
+	ctx := context.Background()
+
+	cli, err := r.getDockerClient()
+	if err != nil {
+		return false, err
+	}
+
+	imageListOpts := types.ImageListOptions{All: true, Filters: filters.NewArgs(filters.KeyValuePair{Key: "reference", Value: invocationImage})}
+
+	imageSummaries, err := cli.Client().ImageList(ctx, imageListOpts)
+	if err != nil {
+		return false, errors.Wrapf(err, "could not list images")
+	}
+
+	if len(imageSummaries) == 0 {
+		return false, nil
+	}
+
+	return true, nil
+}

pkg/porter/stamp.go

@@ -60,6 +60,21 @@ func (p *Porter) IsBundleUpToDate(opts bundleFileOptions) (bool, error) {
 			return false, errors.Wrapf(err, "could not marshal data from %s", opts.CNABFile)
 		}
 
+		// Check whether invocation images exist in host registry.
+		for _, invocationImage := range bun.InvocationImages {
+			isImageCached, err := p.Registry.IsImageCached(invocationImage.Image)
+			if err != nil {
+				return false, err
+			}
+
+			if !isImageCached {
+				if p.Debug {
+					fmt.Fprintln(p.Err, errors.New(fmt.Sprintf("Invocation image %s doesn't exist in the local image cache, will need to build first", invocationImage.Image)))
+				}
+				return false, nil
+			}
+		}
+
 		oldStamp, err := configadapter.LoadStamp(bun)
 		if err != nil {
 			return false, errors.Wrapf(err, "could not load stamp from %s", opts.CNABFile)