/// <summary>
        /// Revokes permissions of a user on a given stream.
        /// </summary>
        /// <param name="streamId">Id of the stream to revoke permissions from</param>
        /// <param name="userId">Id of the user to revoke permissions from</param>
        /// <returns></returns>
        public async Task <bool> StreamRevokePermission(CancellationToken cancellationToken, StreamRevokePermissionInput permissionInput)
        {
            try
            {
                var request = new GraphQLRequest
                {
                    Query =
                        @"mutation streamRevokePermission($permissionParams: StreamRevokePermissionInput!) {
            streamRevokePermission(permissionParams: $permissionParams)
          }",
                    Variables = new
                    {
                        permissionParams = permissionInput
                    }
                };

                var res = await GQLClient.SendMutationAsync <Dictionary <string, object> >(request).ConfigureAwait(false);

                if (res.Errors != null)
                {
                    throw new SpeckleException("Could not revoke permission", res.Errors);
                }

                return((bool)res.Data["streamRevokePermission"]);
            }
            catch (Exception e)
            {
                throw new SpeckleException(e.Message, e);
            }
        }
 /// <summary>
 /// Revokes permissions of a user on a given stream.
 /// </summary>
 /// <param name="streamId">Id of the stream to revoke permissions from</param>
 /// <param name="userId">Id of the user to revoke permissions from</param>
 /// <returns></returns>
 public Task <bool> StreamRevokePermission(StreamRevokePermissionInput permissionInput)
 {
     return(StreamRevokePermission(CancellationToken.None, permissionInput));
 }