Containerization with Docker: Build & Deploy Applications

Revolutionize your development workflow with Docker. This module teaches you how to containerize your applications, ensuring consistency across different environments, simplifying deployment, and enabling scalable solutions. Learn to build, ship, and run any application anywhere.

1. Introduction to Containers & Docker

Understand the fundamental concept of containers and why Docker has become an indispensable tool in modern software development. Explore the benefits of containerization, such as isolation, portability, and efficiency, and get acquainted with Docker's architecture, including the Docker Engine, images, and containers.

# Virtual Machine (VM)
# Runs on a hypervisor, includes a full guest OS,
# slower startup, more resource intensive.
# [Hardware] -> [Host OS] -> [Hypervisor] -> [Guest OS + App]

# Docker Container
# Shares host OS kernel, lightweight, fast startup, efficient.
# [Hardware] -> [Host OS] -> [Docker Engine] -> [Container (Bin/Lib + App)]
            

2. Dockerizing Your First Application

Learn the practical steps to containerize your application. This section guides you through writing a `Dockerfile` to define your application's environment, building Docker images from your `Dockerfile`, and running your application within a Docker container.

# Use an official Node.js runtime as a parent image
FROM node:18-alpine

# Set the working directory inside the container
WORKDIR /app

# Copy package.json and package-lock.json to install dependencies
COPY package*.json ./

# Install application dependencies
RUN npm install

# Copy the rest of the application code
COPY . .

# Expose the port your app runs on
EXPOSE 3000

# Command to run the application
CMD ["node", "app.js"]
            

3. Docker Compose for Multi-Container Apps

For applications with multiple services (e.g., a web app and a database), Docker Compose simplifies orchestration. Learn how to define and run multi-container Docker applications using a `docker-compose.yml` file, making it easy to manage your entire application stack with a single command.

4. Docker Best Practices

Optimize your Docker workflow with best practices. This includes strategies for building efficient and smaller Docker images, ensuring container security, managing data with Docker volumes, and connecting containers using Docker networks for robust and production-ready deployments.

Module Summary

You've mastered containerization with Docker, from understanding its core concepts and writing Dockerfiles to orchestrating multi-container applications with Docker Compose and implementing best practices for efficient and secure deployments. These skills are fundamental for modern cloud-native development.

Next Steps & Related Modules

Further your containerization knowledge with Kubernetes for large-scale orchestration, or integrate Docker into automated pipelines with our DevOps & CI/CD module.