implement listTags tests (#918)

Signed-off-by: Carlos Panato <ctadeu@gmail.com>
google · Feb 11, 2021 · 6a1151b · 6a1151b
1 parent 04be424
commit 6a1151b
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Showing 4 changed files with 116 additions and 1 deletion.
diff --git a/pkg/crane/crane_test.go b/pkg/crane/crane_test.go
@@ -34,7 +34,6 @@ import (
 	"github.com/google/go-containerregistry/pkg/v1/remote"
 )
 
-// TODO(jonjohnsonjr): Test crane.ListTags behavior.
 // TODO(jonjohnsonjr): Test crane.Catalog behavior.
 // TODO(jonjohnsonjr): Test crane.Copy failures.
 func TestCraneRegistry(t *testing.T) {
@@ -148,6 +147,31 @@ func TestCraneRegistry(t *testing.T) {
 		t.Fatal(err)
 	}
 
+	// List Tags
+	// dst variable have: latest and crane-tag
+	tags, err := crane.ListTags(dst)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(tags) != 2 {
+		t.Fatalf("wanted 2 tags, got %d", len(tags))
+	}
+
+	// create 4 tags for dst
+	for i := 1; i < 5; i++ {
+		if err := crane.Tag(dst, fmt.Sprintf("honk-tag-%d", i)); err != nil {
+			t.Fatal(err)
+		}
+	}
+
+	tags, err = crane.ListTags(dst)
+	if err != nil {
+		t.Fatal(err)
+	}
+	if len(tags) != 6 {
+		t.Fatalf("wanted 6 tags, got %d", len(tags))
+	}
+
 	// Delete the non existing image
 	if err := crane.Delete("honk-image"); err == nil {
 		t.Fatal("wanted err, got nil")

diff --git a/pkg/registry/manifest.go b/pkg/registry/manifest.go
@@ -18,16 +18,24 @@ import (
 	"bytes"
 	"crypto/sha256"
 	"encoding/hex"
+	"encoding/json"
 	"fmt"
 	"io"
 	"net/http"
+	"sort"
+	"strconv"
 	"strings"
 	"sync"
 
 	v1 "github.com/google/go-containerregistry/pkg/v1"
 	"github.com/google/go-containerregistry/pkg/v1/types"
 )
 
+type listTags struct {
+	Name string   `json:"name"`
+	Tags []string `json:"tags"`
+}
+
 type manifest struct {
 	contentType string
 	blob        []byte
@@ -48,6 +56,15 @@ func isManifest(req *http.Request) bool {
 	return elems[len(elems)-2] == "manifests"
 }
 
+func isTags(req *http.Request) bool {
+	elems := strings.Split(req.URL.Path, "/")
+	elems = elems[1:]
+	if len(elems) < 4 {
+		return false
+	}
+	return elems[len(elems)-2] == "tags"
+}
+
 // https://github.com/opencontainers/distribution-spec/blob/master/spec.md#pulling-an-image-manifest
 // https://github.com/opencontainers/distribution-spec/blob/master/spec.md#pushing-an-image
 func (m *manifests) handle(resp http.ResponseWriter, req *http.Request) *regError {
@@ -59,6 +76,7 @@ func (m *manifests) handle(resp http.ResponseWriter, req *http.Request) *regErro
 	if req.Method == "GET" {
 		m.lock.Lock()
 		defer m.lock.Unlock()
+
 		c, ok := m.manifests[repo]
 		if !ok {
 			return &regError{
@@ -198,3 +216,60 @@ func (m *manifests) handle(resp http.ResponseWriter, req *http.Request) *regErro
 		Message: "We don't understand your method + url",
 	}
 }
+
+func (m *manifests) handleTags(resp http.ResponseWriter, req *http.Request) *regError {
+	elem := strings.Split(req.URL.Path, "/")
+	elem = elem[1:]
+	repo := strings.Join(elem[1:len(elem)-2], "/")
+	query := req.URL.Query()
+	nStr := query.Get("n")
+	n := 1000
+	if nStr != "" {
+		n, _ = strconv.Atoi(nStr)
+	}
+
+	if req.Method == "GET" {
+		m.lock.Lock()
+		defer m.lock.Unlock()
+
+		c, ok := m.manifests[repo]
+		if !ok {
+			return &regError{
+				Status:  http.StatusNotFound,
+				Code:    "NAME_UNKNOWN",
+				Message: "Unknown name",
+			}
+		}
+
+		var tags []string
+		countTags := 0
+		// TODO: implement pagination https://github.com/opencontainers/distribution-spec/blob/b505e9cc53ec499edbd9c1be32298388921bb705/detail.md#tags-paginated
+		for tag := range c {
+			if countTags >= n {
+				break
+			}
+			countTags++
+			if !strings.Contains(tag, "sha256:") {
+				tags = append(tags, tag)
+			}
+		}
+		sort.Strings(tags)
+
+		tagsToList := listTags{
+			Name: repo,
+			Tags: tags,
+		}
+
+		msg, _ := json.Marshal(tagsToList)
+		resp.Header().Set("Content-Length", fmt.Sprint(len(msg)))
+		resp.WriteHeader(http.StatusOK)
+		io.Copy(resp, bytes.NewReader([]byte(msg)))
+		return nil
+	}
+
+	return &regError{
+		Status:  http.StatusBadRequest,
+		Code:    "METHOD_UNKNOWN",
+		Message: "We don't understand your method + url",
+	}
+}
diff --git a/pkg/registry/registry.go b/pkg/registry/registry.go
@@ -44,6 +44,9 @@ func (r *registry) v2(resp http.ResponseWriter, req *http.Request) *regError {
 	if isManifest(req) {
 		return r.manifests.handle(resp, req)
 	}
+	if isTags(req) {
+		return r.manifests.handleTags(resp, req)
+	}
 	resp.Header().Set("Docker-Distribution-API-Version", "registry/2.0")
 	if req.URL.Path != "/v2/" && req.URL.Path != "/v2" {
 		return &regError{

diff --git a/pkg/registry/registry_test.go b/pkg/registry/registry_test.go
@@ -377,6 +377,19 @@ func TestCalls(t *testing.T) {
 			URL:         "/v2/foo/manifests/sha256:" + sha256String("foo"),
 			Code:        http.StatusAccepted,
 		},
+		{
+			Description: "list tags",
+			Manifests:   map[string]string{"foo/manifests/latest": "foo", "foo/manifests/tag1": "foo"},
+			Method:      "GET",
+			URL:         "/v2/foo/tags/list?n=1000",
+			Code:        http.StatusOK,
+		},
+		{
+			Description: "list non existing tags",
+			Method:      "GET",
+			URL:         "/v2/foo/tags/list?n=1000",
+			Code:        http.StatusNotFound,
+		},
 	}
 
 	for _, tc := range tcs {