OpenShift Service Mesh with Argo Rollouts

Example Repo that does what the title says. You can watch a demo of this repo: HERE

Prereqs

• OpenShift Cluster v4.10+
• Argo Rollout Kubernetes CLI Plugin

This repo assumes that this is a "fresh" cluster. Don't run these steps on a production cluster or a cluster you care about. This is for testing only.

Testing

Highlevel steps to test. These steps assumes you know Argo CD, Argo Rollouts, Istio, and Kubernetes quite a bit.

Fork the repo

First, fork this repo. You will need to change the Application Sets in this directory to point to your fork.

Deploy the Application

After editing the Application Sets in this directory to point to your fork, apply it to your OCP cluster

NOTE Errors are expected in this step. Go get some coffee, go for a walk, then comeback to this.

until oc apply -k bootstrap/overlays/default/; do sleep 15; done

See the App

You should see the app on your browser; first export your Gateway

export GATEWAY_URL=$(oc -n istio-system get route istio-ingressgateway -o jsonpath='{.spec.host}')

Then open in browser, example

firefox $GATEWAY_URL

You should see this

Make update

Update the workloads/canary-app/kustomization.yaml file from blue to yellow. Edit the file by hand but if you're brave, you can run a sed on the file.

sed -i 's/blue/yellow/g' workloads/canary-app/kustomization.yaml

Then commit/push to your fork

git add .
git commit -am "yellow"
git push

Observe

Get status using the plugin (running a watch is helpful)

oc argo rollouts get rollout rollouts-demo -n canary

You'll see that the blue squares turn into yellow ones. It increases every 15 (or so) seconds until you're fully yellow

Auto-Rollback

In the UI, you'll see a slider that causes the application to return a 500 error

Change the application back to blue

sed -i 's/yellow/blue/g' workloads/canary-app/kustomization.yaml

Commit and push...

git add .
git commit -am "blue with errors"
git push

Initiate the rollout by refreshing the Argo CD "canary-app" Application. This will initiate a rollout.

Once the rollout has started, slide the error slider on the application to 100% and watch as the rollout fails

oc argo rollouts get rollout rollouts-demo -n canary

It should fail and it should look something like this...

NAME                                       KIND         STATUS        AGE    INFO
⟳ rollouts-demo                            Rollout      ✖ Degraded    3h27m  
├──# revision:26                                                             
│  ├──⧉ rollouts-demo-6499d5bbb9           ReplicaSet   • ScaledDown  16m    canary,delay:passed
│  └──α rollouts-demo-6499d5bbb9-26        AnalysisRun  ✖ Failed      2m44s  ✖ 3
├──# revision:25                                                             
│  ├──⧉ rollouts-demo-785bb66569           ReplicaSet   ✔ Healthy     41m    stable
│  │  ├──□ rollouts-demo-785bb66569-7gwpj  Pod          ✔ Running     13m    ready:2/2
│  │  ├──□ rollouts-demo-785bb66569-hqmlc  Pod          ✔ Running     13m    ready:2/2
│  │  ├──□ rollouts-demo-785bb66569-rm7j5  Pod          ✔ Running     13m    ready:2/2
│  │  ├──□ rollouts-demo-785bb66569-mjcq5  Pod          ✔ Running     12m    ready:2/2
│  │  ├──□ rollouts-demo-785bb66569-h4tzf  Pod          ✔ Running     12m    ready:2/2
│  │  ├──□ rollouts-demo-785bb66569-v6qn2  Pod          ✔ Running     12m    ready:2/2
│  │  ├──□ rollouts-demo-785bb66569-fvvmb  Pod          ✔ Running     11m    ready:2/2
│  │  ├──□ rollouts-demo-785bb66569-jdt27  Pod          ✔ Running     11m    ready:2/2
│  │  ├──□ rollouts-demo-785bb66569-f6krk  Pod          ✔ Running     11m    ready:2/2
│  │  └──□ rollouts-demo-785bb66569-w7w6w  Pod          ✔ Running     11m    ready:2/2

Your app should have failed back to being all yellow since you had errors during the rollout. To restart/fix this. Move the error slider to 0% and restart the rollout.

oc argo rollouts retry rollout rollouts-demo -n canary

This time, the rollout should finish and you should have blue squares.

http://istio-ingressgateway-istio-system.apps.voxxeddays.w6gk.p1.openshiftapps.com/