images: provide better error for manifest list match error

tonistiigi · tonistiigi · commit 53fe31d6de69 · 2018-06-20T13:43:27.000-07:00
Signed-off-by: Tonis Tiigi &lt;tonistiigi@gmail.com&gt;
diff --git a/images/image.go b/images/image.go
@@ -129,11 +129,14 @@ func (image *Image) Size(ctx context.Context, provider content.Provider, platfor
 // this direction because this abstraction is not needed.`
 func Manifest(ctx context.Context, provider content.Provider, image ocispec.Descriptor, platform string) (ocispec.Manifest, error) {
 	var (
-		matcher platforms.Matcher
-		m       *ocispec.Manifest
+		matcher  platforms.Matcher
+		m        *ocispec.Manifest
+		p        ocispec.Platform
+		wasIndex bool
 	)
 	if platform != "" {
-		p, err := platforms.Parse(platform)
+		var err error
+		p, err = platforms.Parse(platform)
 		if err != nil {
 			return ocispec.Manifest{}, err
 		}
@@ -201,6 +204,8 @@ func Manifest(ctx context.Context, provider content.Provider, image ocispec.Desc
 				}
 			}
 
+			wasIndex = true
+
 			return descs, nil
 
 		}
@@ -210,7 +215,11 @@ func Manifest(ctx context.Context, provider content.Provider, image ocispec.Desc
 	}
 
 	if m == nil {
-		return ocispec.Manifest{}, errors.Wrapf(errdefs.ErrNotFound, "manifest %v", image.Digest)
+		err := errors.Wrapf(errdefs.ErrNotFound, "manifest %v", image.Digest)
+		if wasIndex {
+			err = errors.Wrapf(errdefs.ErrNotFound, "no match for current platform %s in manifest %v", platforms.Format(p), image.Digest)
+		}
+		return ocispec.Manifest{}, err
 	}
 
 	return *m, nil

Original file line number	Diff line number	Diff line change
`@@ -129,11 +129,14 @@ func (image *Image) Size(ctx context.Context, provider content.Provider, platfor`
`129`	`129`	// this direction because this abstraction is not needed.`
`130`	`130`	`func Manifest(ctx context.Context, provider content.Provider, image ocispec.Descriptor, platform string) (ocispec.Manifest, error) {`
`131`	`131`	`var (`
`132`		`- matcher platforms.Matcher`
`133`		`- m *ocispec.Manifest`
	`132`	`+ matcher platforms.Matcher`
	`133`	`+ m *ocispec.Manifest`
	`134`	`+ p ocispec.Platform`
	`135`	`+ wasIndex bool`
`134`	`136`	`)`
`135`	`137`	`if platform != "" {`
`136`		`- p, err := platforms.Parse(platform)`
	`138`	`+ var err error`
	`139`	`+ p, err = platforms.Parse(platform)`
`137`	`140`	`if err != nil {`
`138`	`141`	`return ocispec.Manifest{}, err`
`139`	`142`	`}`
`@@ -201,6 +204,8 @@ func Manifest(ctx context.Context, provider content.Provider, image ocispec.Desc`
`201`	`204`	`}`
`202`	`205`	`}`
`203`	`206`
	`207`	`+ wasIndex = true`
	`208`	`+`
`204`	`209`	`return descs, nil`
`205`	`210`
`206`	`211`	`}`
`@@ -210,7 +215,11 @@ func Manifest(ctx context.Context, provider content.Provider, image ocispec.Desc`
`210`	`215`	`}`
`211`	`216`
`212`	`217`	`if m == nil {`
`213`		`- return ocispec.Manifest{}, errors.Wrapf(errdefs.ErrNotFound, "manifest %v", image.Digest)`
	`218`	`+ err := errors.Wrapf(errdefs.ErrNotFound, "manifest %v", image.Digest)`
	`219`	`+ if wasIndex {`
	`220`	`+ err = errors.Wrapf(errdefs.ErrNotFound, "no match for current platform %s in manifest %v", platforms.Format(p), image.Digest)`
	`221`	`+ }`
	`222`	`+ return ocispec.Manifest{}, err`
`214`	`223`	`}`
`215`	`224`
`216`	`225`	`return *m, nil`