The only changes you need to make here are to the FROM lines in the Dockerfile.
In my sample solution I've changed both lines:
FROM golang:1.17.1-alpine3.14 AS builder
# ...
FROM scratch
That's the latest official Go image version using the latest Alpine version for the builder stage.
The final stage uses scratch, which means there is no base image.
You can copy the solution over the project Dockerfile, and push changes to start a new build:
cp labs/jenkins/solution/Dockerfile labs/jenkins/project/src/
git add labs/jenkins/project/src/Dockerfile
git commit -m 'Jenkins lab solution'
git push labs-jenkins
Check the build at http://localhost:30008/job/kiamol/
The new build should trigger an update and when the Helm upgrade has finished, the app should work in the same way
Test the app with curl localhost:30028. Then pull your two latest images and compare them. My optimized image is 1/3 smaller than the previous one:
> docker image ls courselabs/whoami-lab
REPOSITORY TAG IMAGE ID CREATED
SIZE
courselabs/whoami-lab 21.09-4 061235acbb98 About a minute ago 8.22MB
courselabs/whoami-lab 21.09-3 4deca9963c2a 5 hours ago 12.7MB
Back to the exercises