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Updates for exercise 4-6.

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James Blair
2024-07-25 13:38:06 +12:00
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@ -16,7 +16,6 @@ Enter the [**Helm**](https://www.redhat.com/en/topics/devops/what-is-helm) proje
In simple terms, a **Helm chart** is basically a directory containing a collection of YAML template files, which is zipped into an archive. However the `helm` command line utility has a lot of additional features and is good for customising and overriding specific values in our application templates when we deploy them onto our cluster as well as easily deploying, upgrading or rolling back our application.
## 4.1 - Deploying a helm chart via the web console
It is common for organisations that produce and ship applications to provide their applications to organisations as a **Helm chart**.
@ -39,12 +38,11 @@ tlsRoute: true
```
<Zoom>
|![gitea-deployment](/static/images/gitea-deployment.gif) |
|![gitea-deployment](/static/images/gitea-deployment.gif) |
|:-------------------------------------------------------------------:|
| *Gitea application deployment via helm chart* |
</Zoom>
## 4.2 - Examine deployed application
Returning to the **Topology** view of the **Developer** perspective you will now see the Gitea application being deployed in your `userX` project (this can take a few minutes to complete). Notice how the application is made up of two separate pods, the `gitea-db` database and the `gitea` frontend web server.
@ -53,22 +51,21 @@ Once your gitea pods are both running open the **Route** for the `gitea` web fro
Next, if we click on the overall gitea **Helm release** by clicking on the shaded box surrounding our two Gitea pods we can see the full list of resources deployed by this helm chart, which in addition to the two running pods includes the following:
- 1 **ConfigMap**
- 1 **ImageStream**
- 2 **PersistentVolumeClaims**
- 1 **Route**
- 1 **Secret**
- 2 **Services**
- 1 **ConfigMap**
- 1 **ImageStream**
- 2 **PersistentVolumeClaims**
- 1 **Route**
- 1 **Secret**
- 2 **Services**
> Note: Feel free to try out a `oc explain <resource>` command in your web terminal to learn more about each of the resource types mentioned above, for example `oc explain service`.
<Zoom>
|![helm-resources](/static/images/helm-resources.png) |
|![helm-resources](/static/images/helm-resources.png) |
|:-------------------------------------------------------------------:|
| *Gitea helm release resources created* |
</Zoom>
## 4.3 - Upgrade helm chart
If we want to make a change to the configuration of our Gitea application we can perform a `helm upgrade`. OpenShift has built in support to perform helm upgrades through the web console.
@ -86,12 +83,11 @@ We will be returned to the **Helm releases** view. Notice how the release status
From here it is trivial to perform a **Rollback** to remove our misconfigured update. We'll do that in the next step.
<Zoom>
|![helm-upgrade](/static/images/helm-upgrade.gif) |
|![helm-upgrade](/static/images/helm-upgrade.gif) |
|:-------------------------------------------------------------------:|
| *Attempting a gitea helm upgrade* |
</Zoom>
## 4.4 - Rollback to a previous helm release
Our previous helm upgrade for the Gitea application didn't succeed due to the misconfiguration we supplied. **Helm** has features for rolling back to a previous release through the `helm rollback` command line interface. OpenShift has made this even easier by adding native support for interactive rollbacks in the OpenShift web console so let's give that a go now.
@ -105,12 +101,11 @@ Click the three dot menu to the right hand side of the that helm release and cli
Select the radio button for revision `1` which should be showing a status of `Deployed`, then click **Rollback**.
<Zoom>
|![helm-rollback](/static/images/helm-rollback.gif) |
|![helm-rollback](/static/images/helm-rollback.gif) |
|:-------------------------------------------------------------------:|
| *Rolling back to a previous gitea helm release* |
</Zoom>
## 4.5 - Deleting an application deployed via helm
Along with upgrades and rollbacks **Helm** also makes deleting deployed applications (along with all of their associated resources) straightforward.
@ -126,15 +121,13 @@ Click the three dot menu to the right hand side of the that helm release and cli
Enter the `gitea` confirmation at the prompt and click **Delete**. If you now return to the **Topology** view you will see the gitea application deleting.
<Zoom>
|![helm-delete](/static/images/helm-delete.gif) |
|![helm-delete](/static/images/helm-delete.gif) |
|:-------------------------------------------------------------------:|
| *Deleting the gitea application helm release* |
</Zoom>
## 4.6 - Bonus objective: Artifact Hub
If you have time, take a while to explore https://artifacthub.io/packages/search to see the kinds of applications available in the most popular publicly available Helm Chart repository Artifact Hub.
Well done, you've finished exercise 4! 🎉