Scratch base image for minimal containers in Docker - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the Dockerfile to use the minimal scratch base image.

Docker

FROM [1]
COPY app /app
CMD ["/app"]

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

Ascratch

Balpine

Cubuntu

Ddebian

Attempts:

3 left

💡 Hint

Common Mistakes

Using a full Linux distribution like ubuntu or debian instead of scratch.

Forgetting that scratch is an empty image with no shell.

The scratch image is an empty base image used for minimal containers.

2fill in blank

medium

Complete the Dockerfile to copy the binary into the scratch image.

Docker

FROM scratch
COPY [1] /app
CMD ["/app"]

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

Aapp.exe

Bapp

Csrc/app

Dbin/app

Attempts:

3 left

💡 Hint

Common Mistakes

Copying source code instead of the compiled binary.

Using a wrong path that does not exist.

The binary is usually built into a bin/ directory before copying.

3fill in blank

hard

Fix the error in the Dockerfile to run the binary correctly in scratch.

Docker

FROM scratch
COPY app /app
CMD ["[1]"]

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

A/app

B/bin/bash

Capp

D/bin/sh

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to run shell commands like /bin/sh or /bin/bash which do not exist in scratch.

Using relative paths instead of absolute paths.

In scratch, you must specify the full path to the binary in CMD.

4fill in blank

hard

Fill both blanks to create a minimal Dockerfile that builds a Go binary and uses scratch.

Docker

FROM golang:1.20 AS builder
WORKDIR /src
COPY . .
RUN go build -o [1] .
FROM [2]
COPY --from=builder /src/[1] /app
CMD ["/app"]

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

Aapp

Bscratch

Cubuntu

Dmain

Attempts:

3 left

💡 Hint

Common Mistakes

Using a full Linux base image instead of scratch for the final image.

Naming the binary incorrectly or inconsistently.

The Go binary is often named main by default, and the scratch image is used as the minimal base.

5fill in blank

hard

Fill all three blanks to create a minimal Dockerfile that builds a static Go binary and runs it in scratch.

Docker

FROM golang:1.20 AS builder
WORKDIR /app
COPY . .
RUN CGO_ENABLED=0 GOOS=linux go build -a -installsuffix cgo -o [1] .
FROM [2]
COPY --from=builder /app/[1] /[3]
CMD ["/[3]"]

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

Aapp

Bscratch

Cmain

Dalpine

Attempts:

3 left

💡 Hint

Common Mistakes

Using alpine or other base images instead of scratch for minimal size.

Not setting CGO_ENABLED=0 for static binaries.

The binary is named main, the base image is scratch, and the binary is copied to /main in the container.