Remove protocol-specific authenticator interfaces

This PR removes the gRPC and HTTP-specific interfaces from
the client authenticators. Implementations should now comply
with the main top-level interface, which defines the functions
previously defined at the individual interfaces.

Fixes #4239

Signed-off-by: Juraci Paixão Kröhling <juraci@kroehling.de>

config/configauth/clientauth.go

@@ -27,18 +27,10 @@ import (
 // names from the Authentication configuration.
 type ClientAuthenticator interface {
 	component.Extension
-}
 
-// HTTPClientAuthenticator is a ClientAuthenticator that can be used as an authenticator
-// for the configauth.Authentication option for HTTP clients.
-type HTTPClientAuthenticator interface {
-	ClientAuthenticator
+	// RoundTripper returns a RoundTripper that can be used to authenticate HTTP requests.
 	RoundTripper(base http.RoundTripper) (http.RoundTripper, error)
-}
 
-// GRPCClientAuthenticator is a ClientAuthenticator that can be used as an authenticator for
-// the configauth.Authentication option for gRPC clients.
-type GRPCClientAuthenticator interface {
-	ClientAuthenticator
+	// PerRPCCredentials returns a PerRPCCredentials that can be used to authenticate gRPC requests.
 	PerRPCCredentials() (credentials.PerRPCCredentials, error)
 }

config/configauth/configauth.go

@@ -45,28 +45,15 @@ func (a Authentication) GetServerAuthenticator(extensions map[config.ComponentID
 	return nil, fmt.Errorf("failed to resolve authenticator %q: %w", a.AuthenticatorID, errAuthenticatorNotFound)
 }
 
-// GetHTTPClientAuthenticator attempts to select the appropriate HTTPClientAuthenticator from the list of extensions,
+// GetClientAuthenticator attempts to select the appropriate ClientAuthenticator from the list of extensions,
 // based on the component id of the extension. If an authenticator is not found, an error is returned.
 // This should be only used by HTTP clients.
-func (a Authentication) GetHTTPClientAuthenticator(extensions map[config.ComponentID]component.Extension) (HTTPClientAuthenticator, error) {
+func (a Authentication) GetClientAuthenticator(extensions map[config.ComponentID]component.Extension) (ClientAuthenticator, error) {
 	if ext, found := extensions[a.AuthenticatorID]; found {
-		if auth, ok := ext.(HTTPClientAuthenticator); ok {
+		if auth, ok := ext.(ClientAuthenticator); ok {
 			return auth, nil
 		}
-		return nil, fmt.Errorf("requested authenticator is not a HTTPClientAuthenticator")
-	}
-	return nil, fmt.Errorf("failed to resolve authenticator %q: %w", a.AuthenticatorID, errAuthenticatorNotFound)
-}
-
-// GetGRPCClientAuthenticator attempts to select the appropriate GRPCClientAuthenticator from the list of extensions,
-// based on the component id of the extension. If an authenticator is not found, an error is returned.
-// This should only be used by gRPC clients.
-func (a Authentication) GetGRPCClientAuthenticator(extensions map[config.ComponentID]component.Extension) (GRPCClientAuthenticator, error) {
-	if ext, found := extensions[a.AuthenticatorID]; found {
-		if auth, ok := ext.(GRPCClientAuthenticator); ok {
-			return auth, nil
-		}
-		return nil, fmt.Errorf("requested authenticator is not a GRPCClientAuthenticator")
+		return nil, fmt.Errorf("requested authenticator is not a ClientAuthenticator")
 	}
 	return nil, fmt.Errorf("failed to resolve authenticator %q: %w", a.AuthenticatorID, errAuthenticatorNotFound)
 }

config/configauth/mock_clientauth.go

@@ -25,9 +25,8 @@ import (
 )
 
 var (
-	_            HTTPClientAuthenticator = (*MockClientAuthenticator)(nil)
-	_            GRPCClientAuthenticator = (*MockClientAuthenticator)(nil)
-	errMockError                         = errors.New("mock Error")
+	_            ClientAuthenticator = (*MockClientAuthenticator)(nil)
+	errMockError                     = errors.New("mock Error")
 )
 
 // MockClientAuthenticator provides a mock implementation of GRPCClientAuthenticator and HTTPClientAuthenticator interfaces

config/configgrpc/configgrpc.go

@@ -222,7 +222,7 @@ func (gcs *GRPCClientSettings) ToDialOptions(host component.Host) ([]grpc.DialOp
 			return nil, fmt.Errorf("no extensions configuration available")
 		}
 
-		grpcAuthenticator, cerr := gcs.Auth.GetGRPCClientAuthenticator(host.GetExtensions())
+		grpcAuthenticator, cerr := gcs.Auth.GetClientAuthenticator(host.GetExtensions())
 		if cerr != nil {
 			return nil, cerr
 		}

config/confighttp/confighttp.go

@@ -90,7 +90,7 @@ func (hcs *HTTPClientSettings) ToClient(ext map[config.ComponentID]component.Ext
 			return nil, fmt.Errorf("extensions configuration not found")
 		}
 
-		httpCustomAuthRoundTripper, aerr := hcs.Auth.GetHTTPClientAuthenticator(ext)
+		httpCustomAuthRoundTripper, aerr := hcs.Auth.GetClientAuthenticator(ext)
 		if aerr != nil {
 			return nil, aerr
 		}