Lander-Parren/aelm-workshop-23

AE ALM Workshop for the starters of 2023

Introduction

Hi everybody and welcome to the ALM Workshop of 2023.

Goals:

• Learn new technologies
• Implement CI ALM concepts
• Securely manage secrets for your applications
• Automatically deploy new versions of your application

While it's easier to work with technologies that you use day-to-day, today I would like to try some technologies that you (probably) haven't really worked with yet:

• Golang
• DockerHub
• GitHub DevSpaces
• GitHub Actions
• RedHat OpenShift
  • You can also opt for running Kubernetes locally with Kind (Kubernetes in Docker) or k3d (k3s in docker)

Workshop

The workshop will be divided in several tasks that each represent a checkpoint. If one of the tasks is not working or you ran out of time you can always check-out the branch for that specific checkpoint and catch-up from there.

Tasks

Code repository

The code repository is called aelm-workshop-23.

Task 1

• Start your own CodeSpace from the "main" branch
• Run the Golang application from your CodeSpace & checkout the code
• Create a GitHub Actions pipeline:
  • Create the directory .github/workflows and add a ci.yaml file (You can name the file however you want)
  • Compile the Go code on every branch and creates the artifacts
    • HINT: https://pkg.go.dev/cmd/go#hdr-Compile_packages_and_dependencies
    • HINT: https://docs.github.com/en/actions/automating-builds-and-tests/building-and-testing-go
  • When the code is build succesfully a step should occur which containerizes the application and pushes this to DockerHub, This image should be named as such /aelm-workshop-23
    • HINT: Dockerfile is already provided, but we still need a base image
    • HINT: How will you manage your DockerHub password? Try to push from CodeSpace as well, you might have some secret issues here.

Task 2

• Add SemVer release images
  • This means that when you create a GitHub release with a certain SemVer, the pipeline should be ran again and the docker-image should be /aelm-workshop-23:x.x.x
    • HINT: https://docs.github.com/en/actions/using-workflows/events-that-trigger-workflows#release
• Release your current code as version 1.0.0

Task 3

❗ This task needs to be completed in the aelm-workshop-23-cfg configuration repository

Task 4

❗ This task needs to be completed in the aelm-workshop-23-cfg configuration repository

Task 5

• Update the content of the /workshop endpoint:
  • To include yourself in the list of participants
  • Add a field "SweaterScore" that holds a numeric value of 1-10 on the presentators Christmas Sweater.
    • Provide Validation on this range.
    • The default value of the SweaterScore is setup via an environment variable.
• Release this code as 1.1.0

Task 6

❗ This task needs to be completed in the aelm-workshop-23-cfg configuration repository

Finish?

Congratulations, you've now got a functioning code pipeline!! You can update, release and expose you're application on demand now 👏💪 The next step is to now improve upon this, so that you as a developer can focus solely on producing the code. Choose some of the extra tasks to do, in both repositories are different tasks related to their type.

Extra's

• Do custom tags for your docker builds, right now it takes the branch name but try something as followed:
  • On "main" branch, should be tagged as such :latest
  • On other branches, should be tagged as such :dev- with the hash being a substring of 8 characters
• The dev Openshift environment should always the use the :latest image that is created when a developer pushes code to main and the build succeeds. Create a trigger in your pipeline that automatically restarts the deployment on Openshift
• Add a metrics endpoint to your application that will give you insights into the application performance
• Add an extra endpoint /settings that:
  • Reads a file called settings.json that is stored in /tmp/settings folder
  • When working merge and release this image as a new version
• If you merge to "main" and your build succeeds at an extra step that Restarts your deployment on Openshift to redeploy the main image immediately
• Write a Go test for our /workshop endpoint

Directory structure

/
|── /.devcontainer
    └── devcontainer.json
|── /.github
    |── /workflows
        └── ci.yaml 
|── /workshop-service
    ├── main.go
    |── workshop.go
    ├── go.mod
    └── go.sum
|── .gitignore
|── Dockerfile
└── README.md

Solutions / Tips

In general I tried to work in a branching structure which is named as followed solution/task--

Code repository

Task 1 - Build pipeline

Application

Golang

go run main.go workshop.go

go build -o ../bin/workshop -v ./...

POST command

curl -X POST -H "Content-Type: application/json" -d '{ "name": "AELM Workshop", "date": "07/12/2023", "presentator": "Arnout Hoebreckx", "participants": ["Arnout Hoebreckx"], "sweaterscore": 8 }' http://localhost:3000/workshop

Docker

Build

docker build -t aelm-workshop-23 .

Run / Test

docker run -d --rm -p 3000:3000 --name test-app aelm-workshop-23

curl localhost:3000

Rename

docker tag aelm-workshop-2023:main $DOCKER_USERNAME/aelm-workshop-23:main

Login to repository

docker login -u $DOCKER_USERNAME --> You can create access tokens on your profile to use (use devspaces secrets)

Push to repository

docker push $DOCKER_USERNAME/aelm-workshop-23:main

Task 2 - Release

GitHub has a built-in release mechanism, that you can access through the UI. Important for the builds to check out when