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Building RESTful APIs with C++

Alexander Obregon
14 min readJun 29, 2024

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Introduction

Creating RESTful services using C++ can be both efficient and powerful, leveraging the language’s performance capabilities. In this article, we will explore the basics on how to set up a server, handle HTTP requests, and parse JSON using libraries such as Boost.Beast and nlohmann/json.

RESTful APIs in C++

What is a RESTful API?

RESTful APIs are a cornerstone of modern web development, enabling communication between client applications and servers in a standardized, scalable manner. REST, which stands for Representational State Transfer, is an architectural style that uses a stateless communication protocol, typically HTTP, for accessing and manipulating web resources. RESTful APIs adhere to a set of principles and constraints that make them efficient and easy to use. These principles include:

  1. Statelessness: Each request from a client to a server must contain all the information needed to understand and process the request. The server does not store any client context between requests, making the interaction stateless.
  2. Resource Identification: Resources are identified using URLs (Uniform Resource Locators). Each resource is represented by a unique URL, making it easy to access and manipulate.
  3. Uniform Interface: RESTful APIs use standard HTTP methods like GET, POST, PUT, DELETE, PATCH, and others to perform operations on resources. This uniformity simplifies the design and understanding of the API.
  4. Representation of Resources: Resources can be represented in various formats, such as JSON, XML, or plain text. JSON (JavaScript Object Notation) is the most commonly used format due to its simplicity and ease of use.
  5. Stateless Communication: Each request from the client to the server must contain all the necessary information for the server to fulfill that request. This makes sure that each request can be treated independently.

Benefits of Using C++ for RESTful APIs

C++ is renowned for its performance and efficiency, making it an excellent choice for building high-performance RESTful APIs. Here are some reasons why C++ is advantageous for this purpose:

  1. Performance: C++ provides low-level access to memory and system resources, allowing for optimized performance. This is particularly beneficial for APIs that require high throughput and low latency.
  2. Control: C++ gives developers fine-grained control over system resources and memory management, enabling the creation of highly efficient applications.
  3. Concurrency: C++ supports multithreading and concurrency, which are crucial for handling multiple simultaneous API requests efficiently.
  4. Extensive Libraries: The C++ ecosystem includes powerful libraries such as Boost.Beast for handling HTTP and WebSocket communication, and nlohmann/json for JSON parsing. These libraries simplify the development process and enhance the capabilities of your API.
  5. Cross-Platform Development: C++ is a cross-platform language, allowing you to build and deploy RESTful APIs on various operating systems, including Windows, Linux, and macOS.

Key Components of a RESTful API

To build a RESTful API in C++, you need to understand the key components involved:

  1. HTTP Server: The server handles incoming HTTP requests and sends appropriate responses. In our example, we’ll use Boost.Beast, a C++ library that simplifies the creation of HTTP servers.
  2. Routing: Routing determines how different HTTP requests are handled. It maps URLs to specific functions or methods that process the requests.
  3. Request Handling: Request handlers process the incoming requests, perform necessary operations, and generate appropriate responses. This often involves interacting with a database or other backend services.
  4. Response Generation: Responses are generated based on the outcome of the request handling. This includes setting the HTTP status code, headers, and body content.
  5. JSON Parsing: JSON is a common data format for API communication. Parsing and generating JSON data is essential for handling requests and responses. We’ll use the nlohmann/json library for this purpose.

Setting Up Your Development Environment

Before diving into the implementation, let’s set up the development environment. Make sure you have the following installed:

  1. C++ Compiler: A modern C++ compiler such as GCC, Clang, or MSVC.
  2. CMake: A build system generator that simplifies the build process.
  3. Boost Libraries: A collection of peer-reviewed, portable C++ source libraries. You can download Boost from the Boost website.
  4. nlohmann/json: A popular JSON library for C++. You can download it from the GitHub repository or include it as a single header file.

Once you have the necessary tools and libraries installed, you are ready to start building your RESTful API.

Example Application Overview

To illustrate the process of building a RESTful API with C++, we’ll create a simple application that provides basic CRUD (Create, Read, Update, Delete) operations for managing a collection of data. This example will include:

  1. Server Initialization: Setting up the HTTP server using Boost.Beast.
  2. Routing: Defining routes for different API endpoints.
  3. Request Handling: Implementing handlers for various HTTP methods (GET, POST, PUT, DELETE).
  4. JSON Parsing: Using nlohmann/json to parse and generate JSON data.

By the end of this article, you should have a foundational understanding of how to build RESTful APIs in C++ and will be able to extend and customize the application to suit your needs.

Server Setup with Boost.Beast

Boost.Beast

Boost.Beast is a C++ library built on top of Boost.Asio for handling HTTP and WebSocket communications. It provides a powerful and flexible way to build networked applications, making it an excellent choice for creating RESTful APIs. Boost.Beast abstracts much of the complexity involved in handling HTTP protocols, allowing developers to focus on implementing the logic of their applications.

Setting Up the Project

Before diving into the code, let’s set up a new C++ project. Make sure you have the Boost libraries installed on your system. You can download Boost from the Boost website.

Create a new directory for your project and set up a CMakeLists.txt file. This file will help you manage the build process and include the necessary dependencies. Here is a basic CMakeLists.txt file to get you started:

cmake_minimum_required(VERSION 3.10)
project(RestfulApi)

set(CMAKE_CXX_STANDARD 17)

find_package(Boost REQUIRED COMPONENTS system filesystem)
include_directories(${Boost_INCLUDE_DIRS})

add_executable(RestfulApi main.cpp)
target_link_libraries(RestfulApi ${Boost_LIBRARIES})

In this configuration, we specify that our project requires CMake version 3.10 or higher and that we are using the C++17 standard. We also find the necessary Boost components (system and filesystem) and link them to our project.

Creating the HTTP Server

Next, let’s create a simple HTTP server using Boost.Beast. This server will listen for incoming connections on a specified port and respond with a basic message. Create a main.cpp file and add the following code:

#include <boost/beast/core.hpp>
#include <boost/beast/http.hpp>
#include <boost/beast/version.hpp>
#include <boost/asio/ip/tcp.hpp>
#include <boost/asio/strand.hpp>
#include <boost/config.hpp>
#include <iostream>
#include <memory>
#include <string>
#include <thread>

namespace beast = boost::beast; // from <boost/beast.hpp>
namespace http = beast::http;   // from <boost/beast/http.hpp>
namespace net = boost::asio;    // from <boost/asio.hpp>
using tcp = net::ip::tcp;       // from <boost/asio/ip/tcp.hpp>

// This function produces an HTTP response for the given request.
http::response<http::string_body> handle_request(http::request<http::string_body> const& req) {
    // Respond to GET request with "Hello, World!"
    if (req.method() == http::verb::get) {
        http::response<http::string_body> res{http::status::ok, req.version()};
        res.set(http::field::server, "Beast");
        res.set(http::field::content_type, "text/plain");
        res.keep_alive(req.keep_alive());
        res.body() = "Hello, World!";
        res.prepare_payload();
        return res;
    }

    // Default response for unsupported methods
    return http::response<http::string_body>{http::status::bad_request, req.version()};
}

// This class handles an HTTP server connection.
class Session : public std::enable_shared_from_this<Session> {
    tcp::socket socket_;
    beast::flat_buffer buffer_;
    http::request<http::string_body> req_;

public:
    explicit Session(tcp::socket socket) : socket_(std::move(socket)) {}

    void run() {
        do_read();
    }

private:
    void do_read() {
        auto self(shared_from_this());
        http::async_read(socket_, buffer_, req_, [this, self](beast::error_code ec, std::size_t) {
            if (!ec) {
                do_write(handle_request(req_));
            }
        });
    }

    void do_write(http::response<http::string_body> res) {
        auto self(shared_from_this());
        auto sp = std::make_shared<http::response<http::string_body>>(std::move(res));
        http::async_write(socket_, *sp, [this, self, sp](beast::error_code ec, std::size_t) {
            socket_.shutdown(tcp::socket::shutdown_send, ec);
        });
    }
};

// This class accepts incoming connections and launches the sessions.
class Listener : public std::enable_shared_from_this<Listener> {
    net::io_context& ioc_;
    tcp::acceptor acceptor_;

public:
    Listener(net::io_context& ioc, tcp::endpoint endpoint)
        : ioc_(ioc), acceptor_(net::make_strand(ioc)) {
        beast::error_code ec;

        // Open the acceptor
        acceptor_.open(endpoint.protocol(), ec);
        if (ec) {
            std::cerr << "Open error: " << ec.message() << std::endl;
            return;
        }

        // Allow address reuse
        acceptor_.set_option(net::socket_base::reuse_address(true), ec);
        if (ec) {
            std::cerr << "Set option error: " << ec.message() << std::endl;
            return;
        }

        // Bind to the server address
        acceptor_.bind(endpoint, ec);
        if (ec) {
            std::cerr << "Bind error: " << ec.message() << std::endl;
            return;
        }

        // Start listening for connections
        acceptor_.listen(net::socket_base::max_listen_connections, ec);
        if (ec) {
            std::cerr << "Listen error: " << ec.message() << std::endl;
            return;
        }

        do_accept();
    }

private:
    void do_accept() {
        acceptor_.async_accept(net::make_strand(ioc_), [this](beast::error_code ec, tcp::socket socket) {
            if (!ec) {
                std::make_shared<Session>(std::move(socket))->run();
            }
            do_accept();
        });
    }
};

int main() {
    try {
        auto const address = net::ip::make_address("0.0.0.0");
        unsigned short port = 8080;

        net::io_context ioc{1};

        std::make_shared<Listener>(ioc, tcp::endpoint{address, port})->run();

        ioc.run();
    } catch (const std::exception& e) {
        std::cerr << "Error: " << e.what() << std::endl;
    }
}

Let’s break down the code into its components to understand how each part contributes to building a basic HTTP server using Boost.Beast.

Namespaces and Type Aliases:

  • We define namespaces and type aliases to simplify the code and improve readability.
  • namespace beast = boost::beast; maps boost::beast to beast, making it easier to reference Beast-related functions and classes.
  • namespace http = beast::http; maps beast::http to http, allowing us to use HTTP functionalities provided by Boost.Beast.
  • namespace net = boost::asio; maps boost::asio to net, giving us access to Boost.Asio's networking components.
  • using tcp = net::ip::tcp; creates a type alias tcp for boost::asio::ip::tcp, which we use for TCP networking operations.

HTTP Request Handler:

  • The handle_request function is responsible for processing incoming HTTP requests and generating responses.
  • It takes an http::request<http::string_body> object as its parameter, representing the HTTP request.
  • The function checks the HTTP method of the request. If it is a GET request, it creates an HTTP response with a status code of 200 (OK), sets the content type to text/plain, and the body to "Hello, World!".
  • The response is then returned, ready to be sent back to the client.
http::response<http::string_body> handle_request(http::request<http::string_body> const& req) {
    if (req.method() == http::verb::get) {
        http::response<http::string_body> res{http::status::ok, req.version()};
        res.set(http::field::server, "Beast");
        res.set(http::field::content_type, "text/plain");
        res.keep_alive(req.keep_alive());
        res.body() = "Hello, World!";
        res.prepare_payload();
        return res;
    }
    return http::response<http::string_body>{http::status::bad_request, req.version()};
}

Session Class:

  • The Session class manages individual client connections.
  • It holds a TCP socket (tcp::socket) and a buffer (beast::flat_buffer) for reading data.
  • The run method initiates the reading process by calling do_read.
  • do_read uses http::async_read to asynchronously read an HTTP request from the client. Once the request is read, it calls handle_request to process the request and then do_write to send the response.
  • do_write sends the HTTP response back to the client using http::async_write and then shuts down the socket.
class Session : public std::enable_shared_from_this<Session> {
    tcp::socket socket_;
    beast::flat_buffer buffer_;
    http::request<http::string_body> req_;

public:
    explicit Session(tcp::socket socket) : socket_(std::move(socket)) {}

    void run() {
        do_read();
    }

private:
    void do_read() {
        auto self(shared_from_this());
        http::async_read(socket_, buffer_, req_, [this, self](beast::error_code ec, std::size_t) {
            if (!ec) {
                do_write(handle_request(req_));
            }
        });
    }

    void do_write(http::response<http::string_body> res) {
        auto self(shared_from_this());
        auto sp = std::make_shared<http::response<http::string_body>>(std::move(res));
        http::async_write(socket_, *sp, [this, self, sp](beast::error_code ec, std::size_t) {
            socket_.shutdown(tcp::socket::shutdown_send, ec);
        });
    }
};

Listener Class:

  • The Listener class is responsible for accepting incoming connections on a specified endpoint.
  • It holds an I/O context (net::io_context) and a TCP acceptor (tcp::acceptor).
  • The constructor initializes the acceptor, opens it, sets the option to reuse the address, binds it to the endpoint, and starts listening for connections.
  • The do_accept method uses acceptor_.async_accept to asynchronously accept incoming connections. When a new connection is accepted, it creates a new Session object to handle the connection and calls do_accept again to accept more connections.
class Listener : public std::enable_shared_from_this<Listener> {
    net::io_context& ioc_;
    tcp::acceptor acceptor_;

public:
    Listener(net::io_context& ioc, tcp::endpoint endpoint)
        : ioc_(ioc), acceptor_(net::make_strand(ioc)) {
        beast::error_code ec;

        acceptor_.open(endpoint.protocol(), ec);
        if (ec) {
            std::cerr << "Open error: " << ec.message() << std::endl;
            return;
        }

        acceptor_.set_option(net::socket_base::reuse_address(true), ec);
        if (ec) {
            std::cerr << "Set option error: " << ec.message() << std::endl;
            return;
        }

        acceptor_.bind(endpoint, ec);
        if (ec) {
            std::cerr << "Bind error: " << ec.message() << std::endl;
            return;
        }

        acceptor_.listen(net::socket_base::max_listen_connections, ec);
        if (ec) {
            std::cerr << "Listen error: " << ec.message() << std::endl;
            return;
        }

        do_accept();
    }

private:
    void do_accept() {
        acceptor_.async_accept(net::make_strand(ioc_), [this](beast::error_code ec, tcp::socket socket) {
            if (!ec) {
                std::make_shared<Session>(std::move(socket))->run();
            }
            do_accept();
        });
    }
};

Main Function:

  • The main function initializes the server and starts the I/O context.
  • It creates an I/O context object (net::io_context ioc{1}) and a Listener object, binding it to the address 0.0.0.0 and port 8080.
  • The Listener object starts accepting connections, and ioc.run() starts the I/O context, which will keep running and handling connections until the server is stopped.
int main() {
    try {
        auto const address = net::ip::make_address("0.0.0.0");
        unsigned short port = 8080;

        net::io_context ioc{1};

        std::make_shared<Listener>(ioc, tcp::endpoint{address, port})->run();

        ioc.run();
    } catch (const std::exception& e) {
        std::cerr << "Error: " << e.what() << std::endl;
    }
}

Running the Server

To run the server, compile your project using CMake and run the resulting executable. Open a terminal and navigate to your project directory, then execute the following commands:

mkdir build
cd build
cmake ..
make
./RestfulApi

Open your web browser or use a tool like curl to test the server:

curl http://localhost:8080

You should see the response “Hello, World!” from the server.

Extending the Server

Now that you have a basic HTTP server running, you can extend it to handle various HTTP methods and parse JSON payloads. In the next section, we will cover how to handle different HTTP requests and work with JSON data using the nlohmann/json library.

Handling HTTP Requests and Responses

To build a functional RESTful API, you need to handle various HTTP methods and process JSON payloads effectively. In this section, we will extend our basic server to support multiple HTTP methods (GET, POST, PUT, DELETE) and use the nlohmann/json library for JSON parsing.

Adding JSON Support

First, make sure you have the nlohmann/json library. You can download it from the GitHub repository or include it directly in your project as a single header file.

Handling JSON Requests

Let’s start by updating our handle_request function to handle different HTTP methods and parse JSON payloads.

  • Including nlohmann/json: Add the following include directive at the beginning of your main.cpp file to include the JSON library.
http::response<http::string_body> handle_request(http::request<http::string_body> const& req) {
    if (req.method() == http::verb::get && req.target() == "/api/data") {
        // Handle GET request
        nlohmann::json json_response = {{"message", "This is a GET request"}};
        http::response<http::string_body> res{http::status::ok, req.version()};
        res.set(http::field::server, "Beast");
        res.set(http::field::content_type, "application/json");
        res.keep_alive(req.keep_alive());
        res.body() = json_response.dump();
        res.prepare_payload();
        return res;
    } else if (req.method() == http::verb::post && req.target() == "/api/data") {
        // Handle POST request
        auto json_request = nlohmann::json::parse(req.body());
        std::string response_message = "Received: " + json_request.dump();
        nlohmann::json json_response = {{"message", response_message}};
        http::response<http::string_body> res{http::status::ok, req.version()};
        res.set(http::field::server, "Beast");
        res.set(http::field::content_type, "application/json");
        res.keep_alive(req.keep_alive());
        res.body() = json_response.dump();
        res.prepare_payload();
        return res;
    } else if (req.method() == http::verb::put && req.target() == "/api/data") {
        // Handle PUT request
        auto json_request = nlohmann::json::parse(req.body());
        std::string response_message = "Updated: " + json_request.dump();
        nlohmann::json json_response = {{"message", response_message}};
        http::response<http::string_body> res{http::status::ok, req.version()};
        res.set(http::field::server, "Beast");
        res.set(http::field::content_type, "application/json");
        res.keep_alive(req.keep_alive());
        res.body() = json_response.dump();
        res.prepare_payload();
        return res;
    } else if (req.method() == http::verb::delete_ && req.target() == "/api/data") {
        // Handle DELETE request
        nlohmann::json json_response = {{"message", "Resource deleted"}};
        http::response<http::string_body> res{http::status::ok, req.version()};
        res.set(http::field::server, "Beast");
        res.set(http::field::content_type, "application/json");
        res.keep_alive(req.keep_alive());
        res.body() = json_response.dump();
        res.prepare_payload();
        return res;
    }

    // Default response for unsupported methods
    return http::response<http::string_body>{http::status::bad_request, req.version()};
}

In this extended handle_request function:

  • GET Request: Responds with a JSON message indicating a GET request.
  • POST Request: Parses the JSON body of the request, constructs a response message, and returns it as JSON.
  • PUT Request: Similar to the POST request, it parses the JSON body and returns a message indicating the resource has been updated.
  • DELETE Request: Returns a JSON message indicating that the resource has been deleted.

Handling Different HTTP Methods

To handle different HTTP methods, we extend our handle_request function to check for each method type (GET, POST, PUT, DELETE) and route the requests accordingly.

Full Updated Code Example

Here is the full updated main.cpp file, incorporating the new handle_request function and the necessary includes:

#include <boost/beast/core.hpp>
#include <boost/beast/http.hpp>
#include <boost/beast/version.hpp>
#include <boost/asio/ip/tcp.hpp>
#include <boost/asio/strand.hpp>
#include <boost/config.hpp>
#include <nlohmann/json.hpp>
#include <iostream>
#include <memory>
#include <string>
#include <thread>

namespace beast = boost::beast; // from <boost/beast.hpp>
namespace http = beast::http;   // from <boost/beast/http.hpp>
namespace net = boost::asio;    // from <boost/asio.hpp>
using tcp = net::ip::tcp;       // from <boost/asio/ip/tcp.hpp>

// This function produces an HTTP response for the given request.
http::response<http::string_body> handle_request(http::request<http::string_body> const& req) {
    if (req.method() == http::verb::get && req.target() == "/api/data") {
        // Handle GET request
        nlohmann::json json_response = {{"message", "This is a GET request"}};
        http::response<http::string_body> res{http::status::ok, req.version()};
        res.set(http::field::server, "Beast");
        res.set(http::field::content_type, "application/json");
        res.keep_alive(req.keep_alive());
        res.body() = json_response.dump();
        res.prepare_payload();
        return res;
    } else if (req.method() == http::verb::post && req.target() == "/api/data") {
        // Handle POST request
        auto json_request = nlohmann::json::parse(req.body());
        std::string response_message = "Received: " + json_request.dump();
        nlohmann::json json_response = {{"message", response_message}};
        http::response<http::string_body> res{http::status::ok, req.version()};
        res.set(http::field::server, "Beast");
        res.set(http::field::content_type, "application/json");
        res.keep_alive(req.keep_alive());
        res.body() = json_response.dump();
        res.prepare_payload();
        return res;
    } else if (req.method() == http::verb::put && req.target() == "/api/data") {
        // Handle PUT request
        auto json_request = nlohmann::json::parse(req.body());
        std::string response_message = "Updated: " + json_request.dump();
        nlohmann::json json_response = {{"message", response_message}};
        http::response<http::string_body> res{http::status::ok, req.version()};
        res.set(http::field::server, "Beast");
        res.set(http::field::content_type, "application/json");
        res.keep_alive(req.keep_alive());
        res.body() = json_response.dump();
        res.prepare_payload();
        return res;
    } else if (req.method() == http::verb::delete_ && req.target() == "/api/data") {
        // Handle DELETE request
        nlohmann::json json_response = {{"message", "Resource deleted"}};
        http::response<http::string_body> res{http::status::ok, req.version()};
        res.set(http::field::server, "Beast");
        res.set(http::field::content_type, "application/json");
        res.keep_alive(req.keep_alive());
        res.body() = json_response.dump();
        res.prepare_payload();
        return res;
    }

    // Default response for unsupported methods
    return http::response<http::string_body>{http::status::bad_request, req.version()};
}

// This class handles an HTTP server connection.
class Session : public std::enable_shared_from_this<Session> {
    tcp::socket socket_;
    beast::flat_buffer buffer_;
    http::request<http::string_body> req_;

public:
    explicit Session(tcp::socket socket) : socket_(std::move(socket)) {}

    void run() {
        do_read();
    }

private:
    void do_read() {
        auto self(shared_from_this());
        http::async_read(socket_, buffer_, req_, [this, self](beast::error_code ec, std::size_t) {
            if (!ec) {
                do_write(handle_request(req_));
            }
        });
    }

    void do_write(http::response<http::string_body> res) {
        auto self(shared_from_this());
        auto sp = std::make_shared<http::response<http::string_body>>(std::move(res));
        http::async_write(socket_, *sp, [this, self, sp](beast::error_code ec, std::size_t) {
            socket_.shutdown(tcp::socket::shutdown_send, ec);
        });
    }
};

// This class accepts incoming connections and launches the sessions.
class Listener : public std::enable_shared_from_this<Listener> {
    net::io_context& ioc_;
    tcp::acceptor acceptor_;

public:
    Listener(net::io_context& ioc, tcp::endpoint endpoint)
        : ioc_(ioc), acceptor_(net::make_strand(ioc)) {
        beast::error_code ec;

        // Open the acceptor
        acceptor_.open(endpoint.protocol(), ec);
        if (ec) {
            std::cerr << "Open error: " << ec.message() << std::endl;
            return;
        }

        // Allow address reuse
        acceptor_.set_option(net::socket_base::reuse_address(true), ec);
        if (ec) {
            std::cerr << "Set option error: " << ec.message() << std::endl;
            return;
        }

        // Bind to the server address
        acceptor_.bind(endpoint, ec);
        if (ec) {
            std::cerr << "Bind error: " << ec.message() << std::endl;
            return;
        }

        // Start listening for connections
        acceptor_.listen(net::socket_base::max_listen_connections, ec);
        if (ec) {
            std::cerr << "Listen error: " << ec.message() << std::endl;
            return;
        }

        do_accept();
    }

private:
    void do_accept() {
        acceptor_.async_accept(net::make_strand(ioc_), [this](beast::error_code ec, tcp::socket socket) {
            if (!ec) {
                std::make_shared<Session>(std::move(socket))->run();
            }
            do_accept();
        });
    }
};

int main() {
    try {
        auto const address = net::ip::make_address("0.0.0.0");
        unsigned short port = 8080;

        net::io_context ioc{1};

        std::make_shared<Listener>(ioc, tcp::endpoint{address, port})->run();

        ioc.run();
    } catch (const std::exception& e) {
        std::cerr << "Error: " << e.what() << std::endl;
    }
}

Explanation of the Extended handle_request Function:

GET Request:

  • Checks if the HTTP method is GET and the target URL is /api/data.
  • Constructs a JSON response with a message indicating it’s a GET request.
  • Sets the response content type to application/json and prepares the payload.

POST Request:

  • Checks if the HTTP method is POST and the target URL is /api/data.
  • Parses the JSON body of the request using nlohmann::json::parse.
  • Constructs a response message indicating the received JSON data.
  • Prepares a JSON response and sets the content type to application/json.

PUT Request:

  • Checks if the HTTP method is PUT and the target URL is /api/data.
  • Parses the JSON body of the request.
  • Constructs a response message indicating the updated JSON data.
  • Prepares a JSON response and sets the content type to application/json.

DELETE Request:

  • Checks if the HTTP method is DELETE and the target URL is /api/data.
  • Constructs a JSON response with a message indicating the resource has been deleted.
  • Sets the response content type to application/json and prepares the payload.

Unsupported Methods:

  • Returns a bad request response for any unsupported HTTP methods or URLs.

With this extended functionality, your server can now handle basic CRUD operations using different HTTP methods and work with JSON data. This forms the foundation of a RESTful API in C++.

Conclusion

Building RESTful APIs with C++ can be a powerful way to create high-performance web services. By utilizing libraries like Boost.Beast for HTTP communication and nlohmann/json for JSON parsing, you can develop strong and scalable APIs. In this article, we covered the basics of setting up a server, handling various HTTP requests, and working with JSON data. With these tools and techniques, you are equipped to build and extend your own RESTful APIs in C++, making sure they are both efficient and maintainable.

Thank you for reading! If you find this article helpful, please consider highlighting, clapping, responding or connecting with me on Twitter/X as it’s very appreciated and helps keeps content like this free!

Cpp
C Plus Plus Language
Restful Api
Programming
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Alexander Obregon

Written by Alexander Obregon

24K Followers

Software Engineer, fervent coder & writer. Devoted to learning & assisting others. Connect on LinkedIn: https://www.linkedin.com/in/alexander-obregon-97849b229/

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