This is the open source version of ocp-example-dot-net-app.
This is a simple Hello World app which uses .NET.
It is supposed to be deployed on the OpenShift container platform.
The app's container image is built in an automatically triggered pipeline and the manifest files are automatically deployed by ArgoCD.
The above diagram shows the intended CI/CD workflow for this example app. (Keep in mind that in this case the "Application source code" and "Deployment configuration assets" are in the same repo)
The "Deployment configuration assets" (Kubernetes manifests) are in the /manifests directory. It has the following simplified Kustomize structure:
manifests/
├── base ➀
└── overlays ➁
├── dev ➂
│ ├── active
│ ├── common
│ └── passive
└── prod
├── active
├── common
└── passive
➀ The base directory contains resources which exist across all environments. (e.g. deployment.yaml)
➁ There is an overlay per environment (dev, prod, etc.) Using these overlays, you can apply different resources depending on the environment. E.g. in this example setup, the build pipeline is only in the dev environment.
➂ Inside a environment folder, there is an additional level of differentiation. It is for the active and passive site.
Just push a new commit, the build pipeline will be triggered, and it will be automatically deployed on dev.
Firstly, trigger a new image build by creating and pushing a git tag:
git tag <new-tag>
git push origin <new-tag>This will start the pipeline and a new image will be built using the git tag as its image tag. (The commit message of the commit which you tagged is not allowed to be from the pipeline, since that trigger will be ignored by the pipeline)
In order to deploy the newly built image on prod, update images.newTag in manifests/overlays/prod/common/kustomization.yaml to be your newly created tag.
Be carefull to always pull the latest changes first before creating new commits. Be aware that the update-image-tag step in the pipeline creates a new commit every time the pipeline runs.