api/artifact: add ArtifactDir helper func

To make it easier to construct just the directory path for the
artifact (relative to the storage base path).

api/v1alpha1/artifact.go

@@ -17,7 +17,8 @@ limitations under the License.
 package v1alpha1
 
 import (
-	"fmt"
+	"path"
+	"strings"
 
 	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
 )
@@ -44,8 +45,15 @@ type Artifact struct {
 	LastUpdateTime metav1.Time `json:"lastUpdateTime,omitempty"`
 }
 
+// ArtifactDir returns the artifact dir path in the form of
+// <source-kind>/<source-namespace>/<source-name>
+func ArtifactDir(kind, namespace, name string) string {
+	kind = strings.ToLower(kind)
+	return path.Join(kind, namespace, name)
+}
+
 // ArtifactPath returns the artifact path in the form of
 // <source-kind>/<source-namespace>/<source-name>/<artifact-filename>
 func ArtifactPath(kind, namespace, name, filename string) string {
-	return fmt.Sprintf("%s/%s/%s/%s", kind, namespace, name, filename)
+	return path.Join(ArtifactDir(kind, namespace, name), filename)
 }

controllers/storage.go

@@ -71,7 +71,6 @@ func NewStorage(basePath string, hostname string, timeout time.Duration) (*Stora
 
 // ArtifactFor returns an artifact for the given Kubernetes object
 func (s *Storage) ArtifactFor(kind string, metadata metav1.Object, fileName, revision string) sourcev1.Artifact {
-	kind = strings.ToLower(kind)
 	path := sourcev1.ArtifactPath(kind, metadata.GetNamespace(), metadata.GetName(), fileName)
 	localPath := filepath.Join(s.BasePath, path)
 	url := fmt.Sprintf("http://%s/%s", s.Hostname, path)