🚀 Docker Complete Guide

📌 Overview

This repository contains a comprehensive guide to Docker 🐳, covering essential concepts, hands-on demonstrations, and advanced features like Docker Compose, Networking, and Image Management.

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📚 Topics Covered

🔹 Introduction to Docker

📌 Understanding Docker and its importance in software development.
📌 Difference between Docker Images and Containers.
📌 Basic Docker commands and key concepts.

🔹 Why Docker?

💡 Challenges in traditional software development workflows.
💡 How Docker resolves dependency conflicts and ensures a consistent environment.

🔹 Docker Containers & Images

🔹 What are Containers?
🔹 How Docker Images act as blueprints for containers.
🔹 Portability 🏗️ and Scalability 🚀 benefits.

🔹 Practical Docker Setup & Commands

🔧 Installing Docker Desktop.
🔧 Running containers (docker run, docker ps, docker stop).
🔧 Managing images (docker pull, docker rmi).

🔹 Advanced Docker Features

🌍 Port Binding & Networking between containers.
🛠️ Troubleshooting (docker logs, docker exec).
⚖️ Differences between Docker & Virtual Machines.

🔹 Docker in Application Development

💻 Using Docker for small-scale projects and team collaborations.
🛠️ Building a Node.js 🟢 app with MongoDB inside Docker containers.

🔹 Docker Databases & Networking

🛢️ Running MongoDB inside a container.
🔗 Using Docker Networks for seamless container communication.
📊 Running Mongo Express as a UI for MongoDB.

🔹 Docker Compose

⚙️ Simplifying multi-container applications.
📝 Writing docker-compose.yml for MongoDB & Mongo Express.
💾 Handling data persistence with Docker Volumes.

🔹 Dockerizing Applications

📦 Creating Dockerfiles to package applications.
🖼️ Understanding base images and configuring environment variables.
🚀 Building and running custom Docker images.

🔹 Pushing Images to Docker Hub

📤 Creating a Docker Hub account.
📥 Pushing and pulling Docker Images.
🌐 Docker Networking concepts and Container Communication.

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🚀 Getting Started

🔹 Prerequisites

Ensure you have the following installed:
✅ Docker Desktop
✅ Docker CLI
✅ Docker Hub Account (Optional for image hosting)

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🔹 Clone the Repository

git clone https://github.com/Hifza-Khalid/docker-complete-guide.git
cd docker-complete-guide

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🏗️ Running the Example Application

1️⃣ Run MongoDB in a Docker Container

docker run --name mongodb -d -p 27017:27017 mongo

2️⃣ Run Mongo Express for MongoDB Management

docker run --name mongo-express -d -p 8081:8081 --link mongodb:mongo mongo-express

3️⃣ Verify Running Containers

docker ps

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⚡ Using Docker Compose

Run the following command to start MongoDB & Mongo Express using Docker Compose:

docker-compose up -d

Here’s a sample docker-compose.yml file:

version: '3'
services:
  mongodb:
    image: mongo
    container_name: mongodb
    ports:
      - "27017:27017"

  mongo-express:
    image: mongo-express
    container_name: mongo-express
    ports:
      - "8081:8081"
    environment:
      - ME_CONFIG_MONGODB_SERVER=mongodb

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🏗️ Building a Custom Docker Image

Create and run an application container using a custom Dockerfile:

docker build -t my-app .
docker run -d -p 3000:3000 my-app

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📤 Pushing to Docker Hub

Replace your-dockerhub-username with your actual Docker Hub username before running these commands:

docker tag my-app Hifza-Khalid/docker-complete-guide
docker push Hifza-Khalid/docker-complete-guide

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🛠️ Docker Commands Cheat Sheet

📄 A PDF containing all essential Docker commands is included in this repository for quick reference.

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⚠️ Troubleshooting Common Issues

🔹 Port Already in Use Error
❌ Error: bind: address already in use
✅ Fix: Stop and remove the conflicting container:

docker stop <container_id> && docker rm <container_id>

🔹 Docker Daemon Not Running
❌ Error: Cannot connect to the Docker daemon
✅ Fix: Start the Docker service:

sudo systemctl start docker

🔹 Image Pull Failure
❌ Error: Error response from daemon: pull access denied
✅ Fix: Ensure you're logged in to Docker Hub:

docker login

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📝 Contributing

🚀 Contributions are welcome! Submit pull requests for enhancements, bug fixes, or additional examples.

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📜 License

📄 This project is licensed under the MIT License.

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📧 Contact

📩 For queries or discussions, open an issue or reach out via GitHub discussions.