Oat++

Attention
Version 1.1.0 introduces breaking changes. See the changelog for details.

Oat++ is a modern Web Framework for C++. It's fully loaded and contains all necessary components for effective production level development. It's also light and has a small memory footprint.

Start

• Get Started
• Build For Unix/Linux
• Build For Windows
• Examples

About

• Website
• Supported Platforms
• Latest Benchmarks: 5 Million WebSockets
• Contributing to Oat++

Join Our Community

• Chat on Gitter. Oat++ framework/Lobby
• Follow us on Twitter for latest news. @oatpp_io
• Join community on Reddit. r/oatpp

High Level Overview

• API Controller And Request Mapping
  • Declare Endpoint
  • Add CORS for Endpoint
  • Endpoint with Authorization
• Swagger-UI Annotations
  • Additional Endpoint Info
• API Client - Retrofit / Feign Like Client
  • Declare Client
  • Using API Client
• Object Mapping
  • Declare DTO
  • Serialize DTO Using ObjectMapper

API Controller And Request Mapping

For more info see Api Controller

Declare Endpoint

ENDPOINT("PUT", "/users/{userId}", putUser,
         PATH(Int64, userId),
         BODY_DTO(Object<UserDto>, userDto)) 
{
  userDto->id = userId;
  return createDtoResponse(Status::CODE_200, m_database->updateUser(userDto));
}

Add CORS for Endpoint

For more info see Api Controller / CORS

ADD_CORS(putUser)
ENDPOINT("PUT", "/users/{userId}", putUser,
         PATH(Int64, userId),
         BODY_DTO(Object<UserDto>, userDto)) 
{
  userDto->id = userId;
  return createDtoResponse(Status::CODE_200, m_database->updateUser(userDto));
}

Endpoint with Authorization

For more info see Api Controller / Authorization

using namespace oatpp::web::server::handler;
  
ENDPOINT("PUT", "/users/{userId}", putUser,
         AUTHORIZATION(std::shared_ptr<DefaultBasicAuthorizationObject>, authObject),
         PATH(Int64, userId),
         BODY_DTO(Object<UserDto>, userDto)) 
{
  OATPP_ASSERT_HTTP(authObject->userId == "Ivan" && authObject->password == "admin", Status::CODE_401, "Unauthorized");
  userDto->id = userId;
  return createDtoResponse(Status::CODE_200, m_database->updateUser(userDto));
}

Swagger-UI Annotations

For more info see Endpoint Annotation And API Documentation

Additional Endpoint Info

ENDPOINT_INFO(putUser) {
  // general
  info->summary = "Update User by userId";
  info->addConsumes<Object<UserDto>>("application/json");
  info->addResponse<Object<UserDto>>(Status::CODE_200, "application/json");
  info->addResponse<String>(Status::CODE_404, "text/plain");
  // params specific
  info->pathParams["userId"].description = "User Identifier";
}
ENDPOINT("PUT", "/users/{userId}", putUser,
         PATH(Int64, userId),
         BODY_DTO(Object<UserDto>, userDto)) 
{
  userDto->id = userId;
  return createDtoResponse(Status::CODE_200, m_database->updateUser(userDto));
}

API Client - Retrofit / Feign Like Client

For more info see Api Client

Declare Client

class UserService : public oatpp::web::client::ApiClient {
public:

  API_CLIENT_INIT(UserService)

  API_CALL("GET", "/users", getUsers)
  API_CALL("GET", "/users/{userId}", getUserById, PATH(Int64, userId))

};

Using API Client

auto response = userService->getUserById(id);
auto user = response->readBodyToDto<oatpp::Object<UserDto>>(objectMapper);

Object Mapping

For more info see Data Transfer Object (DTO).

Declare DTO

class UserDto : public oatpp::DTO {

  DTO_INIT(UserDto, DTO)

  DTO_FIELD(Int64, id);
  DTO_FIELD(String, name);

};

Serialize DTO Using ObjectMapper

using namespace oatpp::parser::json::mapping;

auto user = UserDto::createShared();
user->id = 1;
user->name = "Ivan";

auto objectMapper = ObjectMapper::createShared();
auto json = objectMapper->writeToString(user);

Output:

{
  "id": 1,
  "name": "Ivan"
}

Serialize/Deserialize Data In Free Form

While DTO objects apply strict rules on data ser/de, you can also serialize/deserialize data in free form using type oatpp::Any.

oatpp::Fields<oatpp::Any> map = {
  {"title", oatpp::String("Hello Any!")},
  {"listOfAny",
   oatpp::List<oatpp::Any>({
     oatpp::Int32(32),
     oatpp::Float32(0.32),
     oatpp::Boolean(true)
   })
  }
};

auto json = mapper->writeToString(map); 

Output:

{
  "title": "Hello Any!",
  "listOfAny": [
    32,
    0.3199999928474426,
    true
  ]
}

Examples:

REST-API

• ApiClient-Demo - Example project of how-to use Retrofit-like client wrapper (ApiClient) and how it works.
• AsyncApi - Example project of how-to use asynchronous API for handling large number of simultaneous connections.
• CRUD - Example project of how-to create basic CRUD endpoints.

WebSocket

• Can-Chat - Feature-complete rooms-based chat for tens of thousands users. Client plus Server.
• WebSocket - Collection of oatpp WebSocket examples.
• YUV-Websocket-Stream - Example project how-to create a YUV image stream from a V4L device (i.E. Webcam) using websockets.

IoT

• Example-IoT-Hue - Example project how-to create an Philips Hue compatible REST-API that is discovered and controllable by Hue compatible Smart-Home devices like Amazon Alexa or Google Echo.

Streaming

• Media-Stream (Http-Live-Streaming) - Example project of how-to build HLS-streaming server using oat++ Async-API.
• YUV-Websocket-Stream - Example project how-to create a YUV image stream from a V4L device (i.E. Webcam) using websockets.

TLS

• TLS-Libressl - Example project how-to setup secure connection and serve via HTTPS.

Microservices

• Consul - Example project of how-to use oatpp::consul::Client. Integration with Consul.
• Microservices - Example project on how to build microservices with Oat++, and example on how to consolidate those microservices using monolithization technique.

Databases

• MongoDB - Example project how to work with MongoDB using oatpp-mongo mondule. Project is a web-service with basic CRUD and Swagger-UI.
• PostgreSQL - Example of a production grade entity service storing information in PostgreSQL. With Swagger-UI and configuration profiles.