From df98e18eb73cd08feee1c9e7ddf0e629ad510ee7 Mon Sep 17 00:00:00 2001
From: Andrew Block <andy.block@gmail.com>
Date: Sun, 9 Jan 2022 18:47:31 -0600
Subject: [PATCH] Working oci code without providing versions

Signed-off-by: Andrew Block <andy.block@gmail.com>
---
 internal/experimental/registry/client.go |  9 +++++----
 internal/experimental/registry/util.go   | 10 ++++++++++
 internal/resolver/resolver.go            |  4 ++--
 pkg/action/install.go                    |  5 ++---
 pkg/getter/ocigetter.go                  | 25 ++++++++++++++++++++++--
 5 files changed, 42 insertions(+), 11 deletions(-)

diff --git a/internal/experimental/registry/client.go b/internal/experimental/registry/client.go
index a9badb9d5..b3bc49612 100644
--- a/internal/experimental/registry/client.go
+++ b/internal/experimental/registry/client.go
@@ -567,20 +567,21 @@ func (c *Client) Tags(ref string) ([]string, error) {
 		Client:    c.registryAuthorizer,
 	}
 
-	registrtyTags, err := registry.Tags(ctx(c.out, c.debug), &repository)
+	registryTags, err := registry.Tags(ctx(c.out, c.debug), &repository)
 	if err != nil {
 		return nil, err
 	}
 
 	var tagVersions []*semver.Version
-	for _, tag := range registrtyTags {
+	for _, tag := range registryTags {
 		tagVersion, err := semver.StrictNewVersion(tag)
-		if err != nil {
+		if err == nil {
 			tagVersions = append(tagVersions, tagVersion)
 		}
 	}
 
-	sort.Sort(semver.Collection(tagVersions))
+	// Sort the collection
+	sort.Sort(sort.Reverse(semver.Collection(tagVersions)))
 
 	tags := make([]string, len(tagVersions))
 
diff --git a/internal/experimental/registry/util.go b/internal/experimental/registry/util.go
index c421e5639..909a803a3 100644
--- a/internal/experimental/registry/util.go
+++ b/internal/experimental/registry/util.go
@@ -36,6 +36,16 @@ func IsOCI(url string) bool {
 	return strings.HasPrefix(url, fmt.Sprintf("%s://", OCIScheme))
 }
 
+// ContainsTag determines whether a tag is found in a provided list of tags
+func ContainsTag(tags []string, tag string) bool {
+	for _, t := range tags {
+		if tag == t {
+			return true
+		}
+	}
+	return false
+}
+
 // extractChartMeta is used to extract a chart metadata from a byte array
 func extractChartMeta(chartData []byte) (*chart.Metadata, error) {
 	ch, err := loader.LoadArchive(bytes.NewReader(chartData))
diff --git a/internal/resolver/resolver.go b/internal/resolver/resolver.go
index 27ca9929d..36a4803e1 100644
--- a/internal/resolver/resolver.go
+++ b/internal/resolver/resolver.go
@@ -144,10 +144,10 @@ func (r *Resolver) Resolve(reqs []*chart.Dependency, repoNames map[string]string
 					"repository %s is an OCI registry", d.Repository)
 			}
 
-			// Retrive list of tags for repository
+			// Retrieve list of tags for repository
 			tags, err := r.registryClient.Tags(d.Repository)
 			if err != nil {
-				return nil, errors.Wrapf(err, "could not retrieve list of tags for repository", d.Repository)
+				return nil, errors.Wrapf(err, "could not retrieve list of tags for repository %s", d.Repository)
 			}
 
 			vs = make(repo.ChartVersions, len(tags))
diff --git a/pkg/action/install.go b/pkg/action/install.go
index 922f728b0..250dfae95 100644
--- a/pkg/action/install.go
+++ b/pkg/action/install.go
@@ -695,10 +695,9 @@ func (c *ChartPathOptions) LocateChart(name string, settings *cli.EnvSettings) (
 	}
 
 	if registry.IsOCI(name) {
-		if version == "" {
-			return "", errors.New("version is explicitly required for OCI registries")
+		if version != "" {
+			dl.Options = append(dl.Options, getter.WithTagName(version))
 		}
-		dl.Options = append(dl.Options, getter.WithTagName(version))
 	}
 
 	if c.Verify {
diff --git a/pkg/getter/ocigetter.go b/pkg/getter/ocigetter.go
index 45c92749c..fbfcf7133 100644
--- a/pkg/getter/ocigetter.go
+++ b/pkg/getter/ocigetter.go
@@ -20,6 +20,8 @@ import (
 	"fmt"
 	"strings"
 
+	"github.com/pkg/errors"
+
 	"helm.sh/helm/v3/internal/experimental/registry"
 )
 
@@ -50,10 +52,29 @@ func (g *OCIGetter) get(href string) (*bytes.Buffer, error) {
 			registry.PullOptWithProv(true))
 	}
 
-	if version := g.opts.version; version != "" {
-		ref = fmt.Sprintf("%s:%s", ref, version)
+	// Retrieve list of repository tags
+	tags, err := client.Tags(ref)
+	if err != nil {
+		return nil, err
+	}
+
+	//Determine if version provided. If not
+	providedVersion := g.opts.version
+	if g.opts.version == "" {
+		if len(tags) > 0 {
+			providedVersion = tags[0]
+		} else {
+			return nil, errors.Errorf("Unable to locate any tags in provided repository: %s", ref)
+		}
+
+	} else {
+		if !registry.ContainsTag(tags, providedVersion) {
+			return nil, errors.Errorf("Could not located provided version %s in repository %s", providedVersion, ref)
+		}
 	}
 
+	ref = fmt.Sprintf("%s:%s", ref, providedVersion)
+
 	result, err := client.Pull(ref, pullOpts...)
 	if err != nil {
 		return nil, err