Getting Started with Docker: A Comprehensive Guide

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After working for different companies and with multiple people in Web development, I have realised that Docker is one of the important software every web developer should learn or should be aware of at-least.

Here is my simplified guide on Docker.

What is Docker?

Docker is an open-source platform that provides containerisation, a technology for packaging, distributing, and running applications. Docker containers are lightweight and isolated environments that contain all the necessary components to run an application. This includes the application’s code, runtime, system tools, libraries, and configurations. Docker is designed to make it easier to develop, deploy, and manage software applications across different environments.

What is a Docker container?

A Docker container is a lightweight and portable package that includes everything needed to run an application. Containers are isolated from each other and from the host system, ensuring that dependencies and configurations don’t conflict.

Key characteristics of Docker containers:

1. Portability: Containers can run consistently on any system that supports Docker, making it easy to move applications between different environments, such as development, testing, and production.
2. Efficiency: Containers share the host operating system’s kernel, reducing overhead and allowing for higher density of containers on a single host compared to traditional virtualization.
3. Isolation: Containers are in an isolated environments, meaning changes made in one container don’t affect others. This isolation enhances security and reliability.
4. Reproducibility: Containers are created from images, which are immutable and provide a consistent and reproducible runtime environment for applications.

Docker containers are used to streamline software development, simplify deployment, and enhance scalability, making them a valuable tool for modern software development and deployment practices.

Use Cases for Docker:

1. Software Development: Developers use Docker to create consistent development environments, which helps avoid the “it works on my machine” problem. It streamlines collaboration and makes it easier to share development environments with team members.
2. Continuous Integration and Continuous Deployment (CI/CD): Docker is integral to modern CI/CD pipelines. Applications can be containerized, and Docker images can be used to automate the testing and deployment of code changes.
3. Microservices: Docker containers are often used to implement microservices architectures. Each microservice can run in its own container, making it easier to scale, update, and maintain individual components of a larger application.
4. Cloud Computing: Docker is a popular choice for deploying applications in cloud environments. Major cloud providers like AWS, Azure, and Google Cloud offer Docker container services.

Docker Images and Docker files:

Docker images are templates for creating containers. They consist of an application’s code, libraries, and dependencies. Images are often defined by Docker files, which are plain text files containing a set of instructions for building the image. These instructions can include pulling a base image, adding files, setting environment variables, and running commands. Images are stored in Docker registries, like Docker Hub, and can be versioned.

Docker has become a crucial tool in modern software development and deployment. Its ability to package applications and their dependencies into containers simplifies many aspects of the software development lifecycle. It improves efficiency, portability, scalability, and reproducibility, making it a valuable addition to the toolkit of developers, system administrators, and DevOps professionals. Docker’s large and active community, as well as its extensive ecosystem of tools and services, further solidify its importance in the software industry.

Learn How to set up Docker container for Laravel application — here