Docker Lab

Lab for learning about Docker

Pre-reqs

• Docker for Windows: https://store.docker.com/editions/community/docker-ce-desktop-windows
• A text editor such as Visual Studio Code: https://code.visualstudio.com/
• Postman (for sending POST requests to the app): https://www.getpostman.com/apps

To speed up the class, please download the Docker images we'll be using ahead of time by using these commands:

docker pull node:alpine
docker pull redis
docker pull microsoft/aspnetcore-build:latest
docker pull microsoft/aspnetcore:latest

Hands-on

1. Start a Docker container that uses the -v flag to create a volume that serves a node.js app

2. Create a Dockerfile that:

   • Uses the node:alpine image
   • Uses RUN npm install
   • Uses CMD ["npm", "start"]
   • Copies the current directory's files into the image
   • Order the commands to make use of layer caching

3. Use build arguments and labels in the Dockerfile to:

   • Add metadata, such as the version number of the image being built

4. Use environment variables to:

   • Inject an environment variable into the container at runtime
   • Change the environment variable with docker run to change the text displayed on the webpage

5. Use a .dockerignore file to:

   • Prevent files such as the Dockerfile from being copied into the image

6. Create a Docker network named "mynet"

7. Create a Redis container and the node.js app and use --network to put them both on the "mynet" network

8. Put the name of the Redis server into the node.js container by using the -e flag to pass in an environment variable