add extra ref parsing, validation

Signed-off-by: Josh Dolitsky <jdolitsky@gmail.com>

pkg/registry/reference.go

@@ -17,11 +17,18 @@ limitations under the License.
 package registry // import "k8s.io/helm/pkg/registry"
 
 import (
+	"errors"
+	"regexp"
 	"strings"
 
 	"github.com/containerd/containerd/reference"
 )
 
+var (
+	validPortRegEx     = regexp.MustCompile("^([1-9]\\d{0,3}|0|[1-5][0-9]{4}|6[0-4][0-9]{3}|65[0-4][0-9]{2}|655[0-2][0-9]|6553[0-5])$") // adapted from https://stackoverflow.com/a/12968117
+	tooManyColonsError = errors.New("ref may only contain a single colon character (:) unless specifying a port number")
+)
+
 type (
 	// Reference defines the main components of a reference specification
 	Reference struct {
@@ -35,11 +42,67 @@ func ParseReference(s string) (*Reference, error) {
 	if err != nil {
 		return nil, err
 	}
+
+	// convert to our custom type and make necessary mods
 	ref := Reference{&spec}
+	ref.fix()
+
+	// ensure the reference is valid
+	err = ref.validate()
+	if err != nil {
+		return nil, err
+	}
+
 	return &ref, nil
 }
 
-// Repo returns a reference's repo minus the hostname
-func (ref *Reference) Repo() string {
-	return strings.TrimPrefix(strings.TrimPrefix(ref.Locator, ref.Hostname()), "/")
+// fix modifies references that were potentially not parsed properly
+func (spec *Reference) fix() {
+	spec.fixNoTag()
+}
+
+// fixNoTag is a fix for ref strings such as "mychart:1.0.0", which result in missing tag (object)
+func (spec *Reference) fixNoTag() {
+	if spec.Object == "" {
+		parts := strings.Split(spec.Locator, ":")
+		numParts := len(parts)
+		if 0 < numParts {
+			lastIndex := numParts - 1
+			lastPart := parts[lastIndex]
+			if !strings.Contains(lastPart, "/") {
+				spec.Locator = strings.Join(parts[:lastIndex], ":")
+				spec.Object = lastPart
+			}
+		}
+	}
+}
+
+// validate makes sure the ref meets our criteria
+func (spec *Reference) validate() error {
+	return spec.validateColons()
+}
+
+// validateColons verifies the ref only contains one colon max
+// (or two, there might be a port number specified i.e. :5000)
+func (spec *Reference) validateColons() error {
+	if strings.Contains(spec.Object, ":") {
+		return tooManyColonsError
+	}
+	locParts := strings.Split(spec.Locator, ":")
+	locLastIndex := len(locParts) - 1
+	if 1 < locLastIndex {
+		return tooManyColonsError
+	}
+	if 0 < locLastIndex {
+		port := strings.Split(locParts[locLastIndex], "/")[0]
+		if !isValidPort(port) {
+			return tooManyColonsError
+		}
+	}
+	return nil
+}
+
+// isValidPort returns whether or not a string looks like a valid port
+func isValidPort(s string) bool {
+	return validPortRegEx.MatchString(s)
 }

pkg/registry/reference_test.go

@@ -25,25 +25,53 @@ import (
 func TestReference(t *testing.T) {
 	is := assert.New(t)
 
-	// bad ref
+	// bad refs
 	s := ""
 	_, err := ParseReference(s)
-	is.Error(err)
+	is.Error(err, "empty ref")
+
+	s = "my:bad:ref"
+	_, err = ParseReference(s)
+	is.Error(err, "ref contains too many colons (2)")
+
+	s = "my:really:bad:ref"
+	_, err = ParseReference(s)
+	is.Error(err, "ref contains too many colons (3)")
 
 	// good refs
-	s = "localhost:5000/mychart:latest"
+	s = "mychart:1.5.0"
 	ref, err := ParseReference(s)
 	is.NoError(err)
-	is.Equal("localhost:5000", ref.Hostname())
-	is.Equal("mychart", ref.Repo())
+	is.Equal("mychart", ref.Locator)
+	is.Equal("1.5.0", ref.Object)
+
+	s = "myrepo/mychart:1.5.0"
+	ref, err = ParseReference(s)
+	is.NoError(err)
+	is.Equal("myrepo/mychart", ref.Locator)
+	is.Equal("1.5.0", ref.Object)
+
+	s = "mychart:5001:1.5.0"
+	ref, err = ParseReference(s)
+	is.NoError(err)
+	is.Equal("mychart:5001", ref.Locator)
+	is.Equal("1.5.0", ref.Object)
+
+	s = "myrepo:5001/mychart:1.5.0"
+	ref, err = ParseReference(s)
+	is.NoError(err)
+	is.Equal("myrepo:5001/mychart", ref.Locator)
+	is.Equal("1.5.0", ref.Object)
+
+	s = "localhost:5000/mychart:latest"
+	ref, err = ParseReference(s)
+	is.NoError(err)
 	is.Equal("localhost:5000/mychart", ref.Locator)
 	is.Equal("latest", ref.Object)
 
 	s = "my.host.com/my/nested/repo:1.2.3"
 	ref, err = ParseReference(s)
 	is.NoError(err)
-	is.Equal("my.host.com", ref.Hostname())
-	is.Equal("my/nested/repo", ref.Repo())
 	is.Equal("my.host.com/my/nested/repo", ref.Locator)
 	is.Equal("1.2.3", ref.Object)
 }