You can see my solution in lab/Jenkinsfile:
It might seem wasteful to build the images again, but you'll see that Docker uses caching extensively and the new builds happen super quickly.
An alternative is to use the docker image tag command to add a new tag to an existing image and then pull it, but you can't use Compose with that so you'd need to hard-code the image names.
This approach continues to work even if you add new images to your Compose files.
Try pulling a latest image:
docker pull courselabs/rng-api:latest
Then you can inspect it:
docker inspect courselabs/rng-api:latest
In the labels you'll see the build tag and commit hash:
"Labels": {
"build_tag": "compose-7-origin/main",
"commit_sha": "e2ebdf2ca8bf55d5f38c1095ffcad55bc7866039"
}
The build tag includes the Jenkins job name, build number and git branch
Back to the exercises.