Docker for Developers

Welcome to the Docker for Developers documentation! This comprehensive guide covers everything from creating Dockerfiles to orchestrating multi-container applications with Docker Compose.

What You'll Learn

This documentation covers:

• Dockerfile: Building optimized container images with best practices
• Docker Compose: Orchestrating multi-container applications
• CLI Commands: Essential Docker commands for daily workflows
• Networking: Container communication and network configuration
• Volumes: Data persistence and volume management
• Security: Best practices for secure container deployments

Docker Architecture

Prerequisites

Before diving in, you should have:

1. Docker Desktop or Docker Engine installed
2. Basic command line familiarity
3. Understanding of Linux fundamentals

Quick Navigation

Topic Overview

Dockerfile

Master container image creation:

• Base Images: Choosing the right foundation
• Instructions: FROM, RUN, COPY, CMD, ENTRYPOINT
• Multi-stage Builds: Optimizing image size
• Layer Caching: Speeding up builds
• Best Practices: Security and optimization

Docker Compose

Learn multi-container orchestration:

• Services: Defining application components
• Networks: Container communication
• Volumes: Data persistence
• Environment Variables: Configuration management
• Profiles: Environment-specific setups

CLI Commands

Essential commands for daily workflows:

• Container Management: run, start, stop, rm
• Image Management: build, pull, push, tag
• Inspection: logs, exec, inspect
• Cleanup: prune, system df

Docker Workflow

Quick Start

# Check Docker version
docker --version

# Check Docker Compose version
docker compose version

# Verify Docker is running
docker info

# Run a simple container
docker run hello-world

# Run an interactive container
docker run -it ubuntu bash

# Run a web server
docker run -d -p 8080:80 nginx

# Dockerfile
FROM node:20-alpine
WORKDIR /app
COPY package*.json ./
RUN npm install
COPY . .
EXPOSE 3000
CMD ["npm", "start"]

# Build the image
docker build -t my-app .

# Run the container
docker run -d -p 3000:3000 my-app

Container Lifecycle

Key Concepts

# List images
docker images

# Pull an image
docker pull nginx:alpine

# Remove an image
docker rmi nginx:alpine

# Build an image
docker build -t my-app:latest .

# List running containers
docker ps

# List all containers
docker ps -a

# Start a container
docker start container_name

# Stop a container
docker stop container_name

# Remove a container
docker rm container_name

# Create a volume
docker volume create my-data

# List volumes
docker volume ls

# Mount a volume
docker run -v my-data:/app/data my-app

# Bind mount
docker run -v $(pwd):/app my-app

# List networks
docker network ls

# Create a network
docker network create my-network

# Connect container to network
docker network connect my-network container_name

# Run container on specific network
docker run --network my-network my-app

Best Practices Summary