api: adding a gRPC call for revoking refresh tokens.

api/api.proto

@@ -30,7 +30,7 @@ message DeleteClientReq {
   string id = 1;
 }
 
-// DeleteClientResp determines if the. 
+// DeleteClientResp determines if the client is deleted successfully. 
 message DeleteClientResp {
   bool not_found = 1;
 }
@@ -120,6 +120,19 @@ message ListRefreshResp {
   repeated RefreshTokenRef refresh_tokens = 1;
 }
 
+// RevokeRefreshReq is a request to revoke the refresh token of the user-client pair.
+message RevokeRefreshReq {
+  // The "sub" claim returned in the ID Token.
+  string user_id = 1;
+  string client_id = 2;
+}
+
+// RevokeRefreshResp determines if the refresh token is revoked successfully. 
+message RevokeRefreshResp {
+  // Set to true is refresh token was not found and token could not be revoked.
+  bool not_found = 1;
+}
+
 // Dex represents the dex gRPC service.
 service Dex {
   // CreateClient creates a client.
@@ -138,4 +151,8 @@ service Dex {
   rpc GetVersion(VersionReq) returns (VersionResp) {};
   // ListRefresh lists all the refresh token entries for a particular user.
   rpc ListRefresh(ListRefreshReq) returns (ListRefreshResp) {};
+  // RevokeRefresh revokes the refresh token for the provided user-client pair.
+  //
+  // Note that each user-client pair can have only one refresh token at a time.
+  rpc RevokeRefresh(RevokeRefreshReq) returns (RevokeRefreshResp) {};
 }

server/api.go

@@ -16,7 +16,7 @@ import (
 
 // apiVersion increases every time a new call is added to the API. Clients should use this info
 // to determine if the server supports specific features.
-const apiVersion = 0
+const apiVersion = 1
 
 // NewAPI returns a server which implements the gRPC API interface.
 func NewAPI(s storage.Storage, logger logrus.FieldLogger) api.DexServer {
@@ -204,13 +204,13 @@ func (d dexAPI) ListRefresh(ctx context.Context, req *api.ListRefreshReq) (*api.
 	id := new(internal.IDTokenSubject)
 	if err := internal.Unmarshal(req.UserId, id); err != nil {
 		d.logger.Errorf("api: failed to unmarshal ID Token subject: %v", err)
-		return nil, fmt.Errorf("unmarshal ID Token subject: %v", err)
+		return nil, err
 	}
 
 	offlineSessions, err := d.s.GetOfflineSessions(id.UserId, id.ConnId)
 	if err != nil {
 		d.logger.Errorf("api: failed to list refresh tokens: %v", err)
-		return nil, fmt.Errorf("list refresh tokens: %v", err)
+		return nil, err
 	}
 
 	var refreshTokenRefs []*api.RefreshTokenRef
@@ -228,3 +228,39 @@ func (d dexAPI) ListRefresh(ctx context.Context, req *api.ListRefreshReq) (*api.
 		RefreshTokens: refreshTokenRefs,
 	}, nil
 }
+
+func (d dexAPI) RevokeRefresh(ctx context.Context, req *api.RevokeRefreshReq) (*api.RevokeRefreshResp, error) {
+	id := new(internal.IDTokenSubject)
+	if err := internal.Unmarshal(req.UserId, id); err != nil {
+		d.logger.Errorf("api: failed to unmarshal ID Token subject: %v", err)
+		return nil, err
+	}
+
+	var refreshID string
+	updater := func(old storage.OfflineSessions) (storage.OfflineSessions, error) {
+		if refreshID = old.Refresh[req.ClientId].ID; refreshID == "" {
+			return old, fmt.Errorf("user does not have a refresh token for the client = %s", req.ClientId)
+		}
+
+		// Remove entry from Refresh list of the OfflineSession object.
+		delete(old.Refresh, req.ClientId)
+
+		return old, nil
+	}
+
+	if err := d.s.UpdateOfflineSessions(id.UserId, id.ConnId, updater); err != nil {
+		if err == storage.ErrNotFound {
+			return &api.RevokeRefreshResp{NotFound: true}, nil
+		}
+		d.logger.Errorf("api: failed to update offline session object: %v", err)
+		return nil, err
+	}
+
+	// Delete the refresh token from the storage
+	if err := d.s.DeleteRefresh(refreshID); err != nil {
+		d.logger.Errorf("failed to delete refresh token: %v", err)
+		return nil, err
+	}
+
+	return &api.RevokeRefreshResp{}, nil
+}