Why production patterns matter in Docker - Test Your Understanding

Practice - 5 Tasks

1fill in blank

easy

Complete the code to specify the base image in a Dockerfile.

Docker

FROM [1]

Drag options to blanks, or click blank then click option'

Aubuntu:latest

BRUN apt-get update

CCOPY . /app

DCMD python app.py

Attempts:

3 left

💡 Hint

Common Mistakes

Using commands like RUN or COPY instead of a base image.

The FROM instruction sets the base image for the Docker container. Here, ubuntu:latest is a valid base image.

2fill in blank

medium

Complete the code to expose port 80 in the Dockerfile.

Docker

EXPOSE [1]

Drag options to blanks, or click blank then click option'

A443

B80

C22

D8080

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing ports like 22 (SSH) or 443 (HTTPS) when HTTP port 80 is needed.

The EXPOSE instruction tells Docker which port the container listens on. Port 80 is the standard HTTP port.

3fill in blank

hard

Fix the error in the Dockerfile command to run the app.

Docker

CMD ["python", "[1]"]

Drag options to blanks, or click blank then click option'

Aapp.py

Brun.py

Cstart.sh

Dinstall.sh

Attempts:

3 left

💡 Hint

Common Mistakes

Using setup or install scripts instead of the main app script.

The CMD runs the main application. Here, app.py is the correct script to start.

4fill in blank

hard

Fill both blanks to create a volume mount and set environment variable in docker run command.

Docker

docker run -v [1] -e [2]=production myapp

Drag options to blanks, or click blank then click option'

A/host/data:/data

BDEBUG

CENV

D/data:/host/data

Attempts:

3 left

💡 Hint

Common Mistakes

Reversing host and container paths in volume mount.

Using wrong environment variable names.

The -v option mounts the host directory /host/data to container's /data. The -e sets environment variable ENV to 'production'.

5fill in blank

hard

Fill all three blanks to write a Dockerfile snippet that copies files, installs dependencies, and runs the app.

Docker

COPY [1] /app
RUN pip install [2]
CMD ["python", "[3]"]

Drag options to blanks, or click blank then click option'

A.

B-r requirements.txt

Capp.py

Dsrc

Attempts:

3 left

💡 Hint

Common Mistakes

Copying wrong folder path.

Forgetting the '-r' flag in pip install.

Running wrong script name.

COPY . /app copies current folder to /app in container. RUN pip install -r requirements.txt installs dependencies. CMD ["python", "app.py"] runs the app.