oci: Add flag `--plain-http` to enable working with HTTP registries

Add a new flag `--plain-http` to the following commands:
* `helm install`
* `helm pull`
* `helm push`
* `helm template`
* `helm upgrade`
* `helm show`

This flag instructs the registry client to use plain HTTP connections,
thus enabling upload/download of charts from OCI registries served at
an HTTP endpoint.

Signed-off-by: Sanskar Jaiswal <jaiswalsanskar078@gmail.com>

cmd/helm/flags.go

@@ -61,6 +61,7 @@ func addChartPathOptionsFlags(f *pflag.FlagSet, c *action.ChartPathOptions) {
 	f.StringVar(&c.CertFile, "cert-file", "", "identify HTTPS client using this SSL certificate file")
 	f.StringVar(&c.KeyFile, "key-file", "", "identify HTTPS client using this SSL key file")
 	f.BoolVar(&c.InsecureSkipTLSverify, "insecure-skip-tls-verify", false, "skip tls certificate checks for the chart download")
+	f.BoolVar(&c.PlainHTTP, "plain-http", false, "use insecure HTTP connections for the chart download")
 	f.StringVar(&c.CaFile, "ca-file", "", "verify certificates of HTTPS-enabled servers using this CA bundle")
 	f.BoolVar(&c.PassCredentialsAll, "pass-credentials", false, "pass credentials to all domains")
 }

cmd/helm/install.go

@@ -136,7 +136,8 @@ func newInstallCmd(cfg *action.Configuration, out io.Writer) *cobra.Command {
 			return compInstall(args, toComplete, client)
 		},
 		RunE: func(_ *cobra.Command, args []string) error {
-			registryClient, err := newRegistryClient(client.CertFile, client.KeyFile, client.CaFile, client.InsecureSkipTLSverify)
+			registryClient, err := newRegistryClient(client.CertFile, client.KeyFile, client.CaFile,
+				client.InsecureSkipTLSverify, client.PlainHTTP)
 			if err != nil {
 				return fmt.Errorf("missing registry client: %w", err)
 			}

cmd/helm/pull.go

@@ -64,7 +64,8 @@ func newPullCmd(cfg *action.Configuration, out io.Writer) *cobra.Command {
 				client.Version = ">0.0.0-0"
 			}
 
-			registryClient, err := newRegistryClient(client.CertFile, client.KeyFile, client.CaFile, client.InsecureSkipTLSverify)
+			registryClient, err := newRegistryClient(client.CertFile, client.KeyFile, client.CaFile,
+				client.InsecureSkipTLSverify, client.PlainHTTP)
 			if err != nil {
 				return fmt.Errorf("missing registry client: %w", err)
 			}

cmd/helm/push.go

@@ -39,6 +39,7 @@ type registryPushOptions struct {
 	keyFile               string
 	caFile                string
 	insecureSkipTLSverify bool
+	plainHTTP             bool
 }
 
 func newPushCmd(cfg *action.Configuration, out io.Writer) *cobra.Command {
@@ -67,7 +68,7 @@ func newPushCmd(cfg *action.Configuration, out io.Writer) *cobra.Command {
 			return nil, cobra.ShellCompDirectiveNoFileComp
 		},
 		RunE: func(cmd *cobra.Command, args []string) error {
-			registryClient, err := newRegistryClient(o.certFile, o.keyFile, o.caFile, o.insecureSkipTLSverify)
+			registryClient, err := newRegistryClient(o.certFile, o.keyFile, o.caFile, o.insecureSkipTLSverify, o.plainHTTP)
 			if err != nil {
 				return fmt.Errorf("missing registry client: %w", err)
 			}
@@ -77,6 +78,7 @@ func newPushCmd(cfg *action.Configuration, out io.Writer) *cobra.Command {
 			client := action.NewPushWithOpts(action.WithPushConfig(cfg),
 				action.WithTLSClientConfig(o.certFile, o.keyFile, o.caFile),
 				action.WithInsecureSkipTLSVerify(o.insecureSkipTLSverify),
+				action.WithPlainHTTP(o.plainHTTP),
 				action.WithPushOptWriter(out))
 			client.Settings = settings
 			output, err := client.Run(chartRef, remote)
@@ -93,6 +95,7 @@ func newPushCmd(cfg *action.Configuration, out io.Writer) *cobra.Command {
 	f.StringVar(&o.keyFile, "key-file", "", "identify registry client using this SSL key file")
 	f.StringVar(&o.caFile, "ca-file", "", "verify certificates of HTTPS-enabled servers using this CA bundle")
 	f.BoolVar(&o.insecureSkipTLSverify, "insecure-skip-tls-verify", false, "skip tls certificate checks for the chart upload")
+	f.BoolVar(&o.plainHTTP, "plain-http", false, "use insecure HTTP connections for the chart upload")
 
 	return cmd
 }

cmd/helm/root.go

@@ -152,7 +152,7 @@ func newRootCmd(actionConfig *action.Configuration, out io.Writer, args []string
 	flags.ParseErrorsWhitelist.UnknownFlags = true
 	flags.Parse(args)
 
-	registryClient, err := newDefaultRegistryClient()
+	registryClient, err := newDefaultRegistryClient(false)
 	if err != nil {
 		return nil, err
 	}
@@ -257,7 +257,7 @@ func checkForExpiredRepos(repofile string) {
 
 }
 
-func newRegistryClient(certFile, keyFile, caFile string, insecureSkipTLSverify bool) (*registry.Client, error) {
+func newRegistryClient(certFile, keyFile, caFile string, insecureSkipTLSverify, plainHTTP bool) (*registry.Client, error) {
 	if certFile != "" && keyFile != "" || caFile != "" || insecureSkipTLSverify {
 		registryClient, err := newRegistryClientWithTLS(certFile, keyFile, caFile, insecureSkipTLSverify)
 		if err != nil {
@@ -265,21 +265,26 @@ func newRegistryClient(certFile, keyFile, caFile string, insecureSkipTLSverify b
 		}
 		return registryClient, nil
 	}
-	registryClient, err := newDefaultRegistryClient()
+	registryClient, err := newDefaultRegistryClient(plainHTTP)
 	if err != nil {
 		return nil, err
 	}
 	return registryClient, nil
 }
 
-func newDefaultRegistryClient() (*registry.Client, error) {
-	// Create a new registry client
-	registryClient, err := registry.NewClient(
+func newDefaultRegistryClient(plainHTTP bool) (*registry.Client, error) {
+	opts := []registry.ClientOption{
 		registry.ClientOptDebug(settings.Debug),
 		registry.ClientOptEnableCache(true),
 		registry.ClientOptWriter(os.Stderr),
 		registry.ClientOptCredentialsFile(settings.RegistryConfig),
-	)
+	}
+	if plainHTTP {
+		opts = append(opts, registry.ClientOptPlainHTTP())
+	}
+
+	// Create a new registry client
+	registryClient, err := registry.NewClient(opts...)
 	if err != nil {
 		return nil, err
 	}

cmd/helm/show.go

@@ -226,7 +226,8 @@ func runShow(args []string, client *action.Show) (string, error) {
 }
 
 func addRegistryClient(client *action.Show) error {
-	registryClient, err := newRegistryClient(client.CertFile, client.KeyFile, client.CaFile, client.InsecureSkipTLSverify)
+	registryClient, err := newRegistryClient(client.CertFile, client.KeyFile, client.CaFile,
+		client.InsecureSkipTLSverify, client.PlainHTTP)
 	if err != nil {
 		return fmt.Errorf("missing registry client: %w", err)
 	}

cmd/helm/template.go

@@ -73,7 +73,8 @@ func newTemplateCmd(cfg *action.Configuration, out io.Writer) *cobra.Command {
 				client.KubeVersion = parsedKubeVersion
 			}
 
-			registryClient, err := newRegistryClient(client.CertFile, client.KeyFile, client.CaFile, client.InsecureSkipTLSverify)
+			registryClient, err := newRegistryClient(client.CertFile, client.KeyFile, client.CaFile,
+				client.InsecureSkipTLSverify, client.PlainHTTP)
 			if err != nil {
 				return fmt.Errorf("missing registry client: %w", err)
 			}

cmd/helm/upgrade.go

@@ -90,7 +90,8 @@ func newUpgradeCmd(cfg *action.Configuration, out io.Writer) *cobra.Command {
 		RunE: func(cmd *cobra.Command, args []string) error {
 			client.Namespace = settings.Namespace()
 
-			registryClient, err := newRegistryClient(client.CertFile, client.KeyFile, client.CaFile, client.InsecureSkipTLSverify)
+			registryClient, err := newRegistryClient(client.CertFile, client.KeyFile, client.CaFile,
+				client.InsecureSkipTLSverify, client.PlainHTTP)
 			if err != nil {
 				return fmt.Errorf("missing registry client: %w", err)
 			}

pkg/action/install.go

@@ -114,6 +114,7 @@ type ChartPathOptions struct {
 	CertFile              string // --cert-file
 	KeyFile               string // --key-file
 	InsecureSkipTLSverify bool   // --insecure-skip-verify
+	PlainHTTP             bool   // --plain-http
 	Keyring               string // --keyring
 	Password              string // --password
 	PassCredentialsAll    bool   // --pass-credentials
@@ -733,6 +734,7 @@ func (c *ChartPathOptions) LocateChart(name string, settings *cli.EnvSettings) (
 			getter.WithPassCredentialsAll(c.PassCredentialsAll),
 			getter.WithTLSClientConfig(c.CertFile, c.KeyFile, c.CaFile),
 			getter.WithInsecureSkipVerifyTLS(c.InsecureSkipTLSverify),
+			getter.WithPlainHTTP(c.PlainHTTP),
 		},
 		RepositoryConfig: settings.RepositoryConfig,
 		RepositoryCache:  settings.RepositoryCache,

pkg/action/pull.go

@@ -90,6 +90,7 @@ func (p *Pull) Run(chartRef string) (string, error) {
 			getter.WithPassCredentialsAll(p.PassCredentialsAll),
 			getter.WithTLSClientConfig(p.CertFile, p.KeyFile, p.CaFile),
 			getter.WithInsecureSkipVerifyTLS(p.InsecureSkipTLSverify),
+			getter.WithPlainHTTP(p.PlainHTTP),
 		},
 		RegistryClient:   p.cfg.RegistryClient,
 		RepositoryConfig: p.Settings.RepositoryConfig,

pkg/action/push.go

@@ -36,6 +36,7 @@ type Push struct {
 	keyFile               string
 	caFile                string
 	insecureSkipTLSverify bool
+	plainHTTP             bool
 	out                   io.Writer
 }
 
@@ -65,6 +66,13 @@ func WithInsecureSkipTLSVerify(insecureSkipTLSVerify bool) PushOpt {
 	}
 }
 
+// WithPlainHTTP configures the use of plain HTTP connections.
+func WithPlainHTTP(plainHTTP bool) PushOpt {
+	return func(p *Push) {
+		p.plainHTTP = plainHTTP
+	}
+}
+
 // WithOptWriter sets the registryOut field on the push configuration object.
 func WithPushOptWriter(out io.Writer) PushOpt {
 	return func(p *Push) {
@@ -91,6 +99,7 @@ func (p *Push) Run(chartRef string, remote string) (string, error) {
 		Options: []pusher.Option{
 			pusher.WithTLSClientConfig(p.certFile, p.keyFile, p.caFile),
 			pusher.WithInsecureSkipTLSVerify(p.insecureSkipTLSverify),
+			pusher.WithPlainHTTP(p.plainHTTP),
 		},
 	}
 

pkg/getter/getter.go

@@ -37,6 +37,7 @@ type options struct {
 	caFile                string
 	unTar                 bool
 	insecureSkipVerifyTLS bool
+	plainHTTP             bool
 	username              string
 	password              string
 	passCredentialsAll    bool
@@ -96,6 +97,12 @@ func WithTLSClientConfig(certFile, keyFile, caFile string) Option {
 	}
 }
 
+func WithPlainHTTP(plainHTTP bool) Option {
+	return func(opts *options) {
+		opts.plainHTTP = plainHTTP
+	}
+}
+
 // WithTimeout sets the timeout for requests
 func WithTimeout(timeout time.Duration) Option {
 	return func(opts *options) {

pkg/getter/ocigetter.go

@@ -137,12 +137,15 @@ func (g *OCIGetter) newRegistryClient() (*registry.Client, error) {
 		g.transport.TLSClientConfig = tlsConf
 	}
 
-	client, err := registry.NewClient(
-		registry.ClientOptHTTPClient(&http.Client{
-			Transport: g.transport,
-			Timeout:   g.opts.timeout,
-		}),
-	)
+	opts := []registry.ClientOption{registry.ClientOptHTTPClient(&http.Client{
+		Transport: g.transport,
+		Timeout:   g.opts.timeout,
+	})}
+	if g.opts.plainHTTP {
+		opts = append(opts, registry.ClientOptPlainHTTP())
+	}
+
+	client, err := registry.NewClient(opts...)
 
 	if err != nil {
 		return nil, err

pkg/pusher/ocipusher.go

@@ -139,9 +139,12 @@ func (pusher *OCIPusher) newRegistryClient() (*registry.Client, error) {
 		return registryClient, nil
 	}
 
-	registryClient, err := registry.NewClient(
-		registry.ClientOptEnableCache(true),
-	)
+	opts := []registry.ClientOption{registry.ClientOptEnableCache(true)}
+	if pusher.opts.plainHTTP {
+		opts = append(opts, registry.ClientOptPlainHTTP())
+	}
+
+	registryClient, err := registry.NewClient(opts...)
 	if err != nil {
 		return nil, err
 	}

pkg/pusher/pusher.go

@@ -32,6 +32,7 @@ type options struct {
 	keyFile               string
 	caFile                string
 	insecureSkipTLSverify bool
+	plainHTTP             bool
 }
 
 // Option allows specifying various settings configurable by the user for overriding the defaults
@@ -61,6 +62,12 @@ func WithInsecureSkipTLSVerify(insecureSkipTLSVerify bool) Option {
 	}
 }
 
+func WithPlainHTTP(plainHTTP bool) Option {
+	return func(opts *options) {
+		opts.plainHTTP = plainHTTP
+	}
+}
+
 // Pusher is an interface to support upload to the specified URL.
 type Pusher interface {
 	// Push file content by url string

pkg/registry/client.go

@@ -61,6 +61,7 @@ type (
 		registryAuthorizer *registryauth.Client
 		resolver           remotes.Resolver
 		httpClient         *http.Client
+		plainHTTP          bool
 	}
 
 	// ClientOption allows specifying various settings configurable by the user for overriding the defaults
@@ -93,6 +94,9 @@ func NewClient(options ...ClientOption) (*Client, error) {
 		if client.httpClient != nil {
 			opts = append(opts, auth.WithResolverClient(client.httpClient))
 		}
+		if client.plainHTTP {
+			opts = append(opts, auth.WithResolverPlainHTTP())
+		}
 		resolver, err := client.authorizer.ResolverWithOpts(opts...)
 		if err != nil {
 			return nil, err
@@ -177,6 +181,12 @@ func ClientOptHTTPClient(httpClient *http.Client) ClientOption {
 	}
 }
 
+func ClientOptPlainHTTP() ClientOption {
+	return func(c *Client) {
+		c.plainHTTP = true
+	}
+}
+
 type (
 	// LoginOption allows specifying various settings on login
 	LoginOption func(*loginOperation)
@@ -626,23 +636,14 @@ func (c *Client) Tags(ref string) ([]string, error) {
 	repository := registryremote.Repository{
 		Reference: parsedReference,
 		Client:    c.registryAuthorizer,
+		PlainHTTP: c.plainHTTP,
 	}
 
 	var registryTags []string
 
-	for {
-		registryTags, err = registry.Tags(ctx(c.out, c.debug), &repository)
-		if err != nil {
-			// Fallback to http based request
-			if !repository.PlainHTTP && strings.Contains(err.Error(), "server gave HTTP response") {
-				repository.PlainHTTP = true
-				continue
-			}
-			return nil, err
-		}
-
-		break
-
+	registryTags, err = registry.Tags(ctx(c.out, c.debug), &repository)
+	if err != nil {
+		return nil, err
 	}
 
 	var tagVersions []*semver.Version