Add oci:// prefix

Signed-off-by: Stefan Prodan <stefan.prodan@gmail.com>

internal/oci/url.go

@@ -0,0 +1,54 @@
+/*
+Copyright 2022 The Flux authors
+
+Licensed under the Apache License, Version 2.0 (the "License");
+you may not use this file except in compliance with the License.
+You may obtain a copy of the License at
+
+    http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+distributed under the License is distributed on an "AS IS" BASIS,
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+See the License for the specific language governing permissions and
+limitations under the License.
+*/
+
+package oci
+
+import (
+	"fmt"
+	"strings"
+
+	sourcev1 "github.com/fluxcd/source-controller/api/v1beta2"
+	"github.com/google/go-containerregistry/pkg/name"
+)
+
+// ParseArtifactURL validates the OCI URL and returns the address of the artifact.
+func ParseArtifactURL(ociURL string) (string, error) {
+	if !strings.HasPrefix(ociURL, sourcev1.OCIRepositoryPrefix) {
+		return "", fmt.Errorf("URL must be in format 'oci://<domain>/<org>/<repo>'")
+	}
+
+	url := strings.TrimPrefix(ociURL, sourcev1.OCIRepositoryPrefix)
+	if _, err := name.ParseReference(url); err != nil {
+		return "", fmt.Errorf("'%s' invalid URL: %w", ociURL, err)
+	}
+
+	return url, nil
+}
+
+// ParseRepositoryURL validates the OCI URL and returns the address of the artifact repository.
+func ParseRepositoryURL(ociURL string) (string, error) {
+	if !strings.HasPrefix(ociURL, sourcev1.OCIRepositoryPrefix) {
+		return "", fmt.Errorf("URL must be in format 'oci://<domain>/<org>/<repo>'")
+	}
+
+	url := strings.TrimPrefix(ociURL, sourcev1.OCIRepositoryPrefix)
+	ref, err := name.ParseReference(url)
+	if err != nil {
+		return "", fmt.Errorf("'%s' invalid URL: %w", ociURL, err)
+	}
+
+	return ref.Context().Name(), nil
+}