Assignments > Lab 4: Intro to Docker

Recommended: install with Homebrew:

brew install --cask docker
docker --version

Then start Docker Desktop (Spotlight → Docker.app). Wait until Docker says it is running.

Verify with:

docker run hello-world

You should see a line that says Hello from Docker!. That means the install worked.

1. Install Docker Desktop from Docker’s official guide: Install Docker Desktop on Windows.
2. During setup, choose the WSL 2 backend if asked.
3. Do not install or switch to Windows containers / WSLc. This lab uses Linux containers through Docker Desktop.
4. Start Docker Desktop and wait until it says it is running.
5. Open PowerShell or your WSL Ubuntu terminal and verify with:

docker run hello-world

You should see Hello from Docker!.

1. On GitHub: open your fork of class-exercises-fall2026 and sync it with the class repo (csci338/class-exercises-fall2026) using Sync fork / Update branch.

2. On your computer, in your local class-exercises-fall2026 folder:

   git checkout main
   git pull
   git checkout -b lab04-b
   git branch

3. Confirm git branch shows * lab04-b.

1. Keep Docker Desktop running.

2. In a terminal, run:

   docker run -dp 80:80 docker/getting-started

3. Open http://localhost in your browser.

4. Complete these tutorial sections (Sharing Our App and Image Building Best Practices are optional):

   1. Getting Started
   2. Our Application
   3. Updating Our App
   4. Optional Sharing Our App
   5. Persisting our DB
   6. Using Bind Mounts
   7. Multi-Container Apps
   8. Using Docker Compose
   9. Optional Image Building Best Practices

5. As you work, answer the questions in class-exercises-fall2026/lab04/answers.md.

When the tutorial is done, your repo should look like this:

class-exercises-fall2026/
  lab04/
    answers.md          ← your written answers
    app/                ← the app folder from the tutorial
      Dockerfile
      docker-compose.yml
      ...other tutorial files...

If the tutorial created app/ somewhere else, move it into lab04/app/ before you submit.

A container is an isolated process that runs on a host machine (for example, your laptop).

• It can run on any machine (and be moved to the cloud)
• It is isolated from other containers and processes
• It is created from an image, and can be stopped, started, or deleted
• Source: https://docs.docker.com/get-started/

A Docker image is a lightweight, read-only template or “blueprint” that contains everything needed to run an application. Images are used to create containers. Dependencies, configurations, scripts, binaries, and metadata (such as environment variables and a default command) live in the image.

• Source: https://docs.docker.com/get-started/

Image : Class :: Container : Object

Images

Containers