To consolidate Docker knowledge, this chapter will explore practical examples of deploying web applications and APIs in containers. These examples will illustrate how to containerize and deploy modern services in Docker.

Example 1: Deploying a Web Application on Docker

Suppose we have a simple web application built with Nginx. Docker facilitates packaging the application into a production-ready image.

Step 1: Create the Dockerfile

Create a Dockerfile that uses Nginx as a web server:

dockerfile

Step 2: Build and Run the Image

To build the application image, run the following command:

bash

Example 2: Deploying a Node.js API

Now let's consider an API built in Node.js. Docker allows packaging and consistently deploying the API in any environment.

Step 1: Create the Dockerfile for the API

The following Dockerfile creates an image for a Node.js API:

dockerfile

Step 2: Build and Run the API

Build the image and run the API in a container:

bash

Example 3: Deploying Applications in Docker Compose

Docker Compose simplifies the configuration of multi-container applications. In this example, we will deploy a web application with a MySQL database.

Step 1: Create the docker-compose.yml File

This file defines an application composed of a web server and a database:

yaml

Step 2: Bring Up the Application with Docker Compose

Run the application with the following command:

bash

Testing and Verification

Once the containers are running, verify the deployment by accessing the web server at port 8080 and using tools like curl or Postman to test the API at port 3000.

Conclusion

These practical examples demonstrate how to deploy web applications and APIs using Docker and Docker Compose, enabling easy and scalable management. With these concepts, it is possible to efficiently containerize and deploy applications in any environment. We hope these examples are useful for implementing your own projects and continuing to explore the possibilities.