Introduction

In today’s tech-driven world, developing and deploying REST APIs is essential for building scalable and interoperable systems. If you’re working with C++ as your programming language of choice, one powerful option for implementing REST APIs is using the cpprestsdk framework. In this article, we will explore how to deploy C++ REST APIs with Docker and cpprestsdk, enabling you to easily containerize and deploy your APIs.

Prerequisites

Before we dive into the deployment process, make sure you have the following prerequisites installed on your development machine:

• Docker: A containerization platform that allows you to package your application and its dependencies into a container.
• cpprestsdk: A C++ library for building RESTful web services. It provides a powerful set of features for handling HTTP requests and responses.

Building the C++ REST API

First, let’s create a C++ REST API using cpprestsdk. Here’s an example code snippet:

#include <cpprest/http_listener.h>
#include <cpprest/json.h>

using namespace web;
using namespace http;
using namespace http::experimental::listener;

int main() {
    http_listener listener("http://localhost:8080/api");
  
    listener.support(methods::GET, [](http_request request) {
        json::value response;
        response["message"] = json::value::string("Hello, World!");

        request.reply(status_codes::OK, response);
    });

    listener.open().wait();

    std::cout << "Server is listening on http://localhost:8080/api" << std::endl;

    std::getchar();

    listener.close().wait();

    return 0;
}

In this example, we’re defining an HTTP listener that listens for GET requests on http://localhost:8080/api. When it receives a request, it replies with a simple JSON message saying “Hello, World!”.

Dockerizing the C++ REST API

Now that we have our C++ REST API code ready, let’s dockerize it to make deployment easier.

1. Create a file named Dockerfile (without any file extensions) in the same directory as your C++ source code.

2. Open the Dockerfile and add the following lines:

FROM ubuntu:latest

RUN apt-get update \
    && apt-get install -y build-essential cmake libcpprest-dev \
    && rm -rf /var/lib/apt/lists/*

COPY . /app
WORKDIR /app

RUN cmake . \
    && make -j4

EXPOSE 8080

CMD ["./your_CPP_API"]

In this Dockerfile, we’re using a base ubuntu image, installing the necessary dependencies, and copying the source code into the container. We then run cmake to generate the build files, followed by the make command to build the executable. Finally, we expose port 8080 and specify the command to be executed when the container starts.

1. Open a terminal and navigate to the directory containing your C++ source code and Dockerfile.

2. Build the Docker image by running the following command:

docker build -t your_image_name .

1. Once the image is built, you can run the container using the following command:

docker run -p 8080:8080 your_image_name

Now your C++ REST API is running inside a Docker container, accessible on http://localhost:8080/api. You can test it by sending a GET request to that URL.

Conclusion

Congratulations! You’ve successfully deployed a C++ REST API using Docker and the cpprestsdk framework. Dockerizing your applications helps in easy deployment and scalability. Feel free to explore more features of cpprestsdk or customize your Dockerfile to suit your requirements. Happy coding!

#cpp #Docker