Squashing layers in Docker - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the Dockerfile command to squash layers during build.

Docker

docker build [1] .

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

A--tag

B--rm

C--squash

D--pull

Attempts:

3 left

💡 Hint

Common Mistakes

Using --tag instead of --squash

Forgetting to add the --squash option

Using --rm which removes intermediate containers but does not squash layers

The --squash option tells Docker to squash all layers into one during the build.

2fill in blank

medium

Complete the Docker build command to tag the image while squashing layers.

Docker

docker build [1] myimage:latest --squash .

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

A--tag

B--rm

C--quiet

D--pull

Attempts:

3 left

💡 Hint

Common Mistakes

Using --pull which updates base images but does not tag

Using --rm which removes intermediate containers

Using --quiet which suppresses output

The --tag option assigns a name and tag to the image being built.

3fill in blank

hard

Fix the error in this Dockerfile line to squash layers by combining RUN commands.

Docker

RUN apt-get update && apt-get install -y curl && [1]

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

Aapt-get clean

Bapt-get remove

Capt-get upgrade

Dapt-get autoremove

Attempts:

3 left

💡 Hint

Common Mistakes

Using apt-get remove which deletes packages

Using apt-get upgrade which updates packages but does not clean

Using apt-get autoremove which removes unused packages but not cache

Adding apt-get clean after installing packages helps reduce image size by cleaning cache, effectively squashing changes in one layer.

4fill in blank

hard

Fill both blanks to create a squashed image by combining commands in one RUN statement.

Docker

RUN [1] && [2] && rm -rf /var/lib/apt/lists/*

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

Aapt-get update

Bapt-get install -y git

Capt-get clean

Dapt-get upgrade

Attempts:

3 left

💡 Hint

Common Mistakes

Using apt-get clean before install

Using apt-get upgrade instead of install

Not chaining commands properly

Combining apt-get update and apt-get install -y git in one RUN command reduces layers and helps squash them.

5fill in blank

hard

Fill all three blanks to create a dictionary comprehension that filters and transforms Docker image tags.

Docker

tags = {tag[1]:tag[2] for tag in images if tag[3] 'latest'}

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

A.split('-')[0]

B.upper()

C!=

D==

Attempts:

3 left

💡 Hint

Common Mistakes

Using '==' instead of '!=' in the filter

Not splitting the tag for the key

Not converting tag to uppercase

This comprehension splits the tag at '-', takes the first part as key, converts the tag to uppercase as value, and filters out tags equal to 'latest'.