Docker Mastery

Build Apps That Deploy Anywhere

Running Applications Inside Docker Containers

Key Takeaways

  • Universal Docker Workflow: The containerization process is identical regardless of programming language or application type - once you understand the workflow, it applies universally
  • Volume Mounting Concept: The -v flag mounts applications from your host machine's file system into a working directory inside the Docker container, creating a bridge between environments
  • Docker Images as Snapshots: Images are preconfigured environment snapshots taken at specific points in time, packaged and uploaded to repositories for reuse
  • DockerHub Repository: DockerHub functions as "GitHub for Docker images" - the central registry where official and community images are stored and distributed
  • Slim Image Advantage: Slim image variants (like python:3.8-slim) contain only essential components needed to run applications, resulting in faster downloads and smaller footprints
  • Container Naming Strategy: Always name your containers using --name flag - it facilitates container communication, networking, and management in complex applications
  • Container Lifecycle Management: Use --rm flag for automatic cleanup, docker ps -a to view all containers, and docker rm to remove stopped containers
  • Image vs Container Commands: docker rm removes containers, docker image rm removes images - understanding this distinction is crucial for proper Docker cache management
  • Working Directory Structure: Applications run from specific paths inside containers (e.g., /app) - commands must reference these internal paths, not host machine paths