text: ////////////////////////////////////////////////////////////////////////////////
  /// DISCLAIMER
  ///
  /// Copyright 2014-2016 ArangoDB GmbH, Cologne, Germany
  /// Copyright 2004-2014 triAGENS GmbH, Cologne, Germany
  ///
  /// Licensed under the Apache License, Version 2.0 (the "License");
  /// you may not use this file except in compliance with the License.
  /// You may obtain a copy of the License at
  ///
  ///     http://www.apache.org/licenses/LICENSE-2.0
  ///
  /// Unless required by applicable law or agreed to in writing, software
  /// distributed under the License is distributed on an "AS IS" BASIS,
  /// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  /// See the License for the specific language governing permissions and
  /// limitations under the License.
  ///
  /// Copyright holder is ArangoDB GmbH, Cologne, Germany
  ///
  /// @author Dr. Frank Celler
  ////////////////////////////////////////////////////////////////////////////////
  
  #ifndef ARANGOD_REST_HANDLER_REST_BASE_HANDLER_H
  #define ARANGOD_REST_HANDLER_REST_BASE_HANDLER_H 1
  
  #include "GeneralServer/RestHandler.h"
  
  #include "Rest/GeneralResponse.h"
  
  namespace arangodb {
  namespace transaction {
  class Context;
  }
  
  namespace velocypack {
  class Builder;
  struct Options;
  class Slice;
  }  // namespace velocypack
  
  class RestBaseHandler : public rest::RestHandler {
   public:
    explicit RestBaseHandler(GeneralRequest*, GeneralResponse*);
  
    void handleError(basics::Exception const&) override;
  
   public:
    // generates a result from VelocyPack
    template <typename Payload>
    void generateResult(rest::ResponseCode, Payload&&);
  
    // generates a result from VelocyPack
    template <typename Payload>
    void generateResult(rest::ResponseCode, Payload&&, VPackOptions const*);
  
    // generates a result from VelocyPack
    template <typename Payload>
    void generateResult(rest::ResponseCode, Payload&&,
                        std::shared_ptr<transaction::Context> context);
  
    /// convenience function akin to generateError,
    /// renders payload in 'result' field
    /// adds proper `error`, `code` fields
    void generateOk(rest::ResponseCode, velocypack::Slice const&);
  
    /// Add `error` and `code` fields into your response
    void generateOk(rest::ResponseCode, velocypack::Builder const&);
  
    // generates a canceled message
    void generateCanceled();
  
   protected:
    /// @brief parses the body as VelocyPack
    std::shared_ptr<arangodb::velocypack::Builder> parseVelocyPackBody(bool& success);
  
    /// @brief parses the body as VelocyPack
    arangodb::velocypack::Slice parseVPackBody(bool& success);
  
    template <typename Payload>
    void writeResult(Payload&&, arangodb::velocypack::Options const& options);
  };
  }  // namespace arangodb
  
  #endif
  