latency-driven-workload-placement

#Requirements:
1x RHACM HUB
2x+ Managed Clusters

#Join clusters
Go ahead and make sure that all your ManagedClusters joined the RHACM Hub and are in ready state.

#ManagedClusters must have labels that will be used for app placement together with the LatencyCheck operator. For example, if we plan to use the label `ddosify` as the one used by the operator when creating the PlacementRule, that label should have the following values:

- If using locationMatchingStrategy set to city: NA.US.TX.SA
- If using locationMatchingStrategy set to state: NA.US.TX
- If using locationMatchingStrategy set to country: NA.US
- If using locationMatchingStrategy set to continent: NA

#Create the demo namespace
1. Create the ddosify namespace in the HUB cluster:
oc create namespace ddosify

#Run the Fake ddosify api
The fake api can be found here https://github.com/RHsyseng/ddosify-tooling/tree/main/tooling/fake-api. 

For the sake of simplicity, we are running the Fake ddosify API in our Hub cluster. In order to deploy it follow the steps below:

1. Create the fake-api deployment:
oc -n ddosify apply -f https://raw.githubusercontent.com/RHsyseng/ddosify-tooling/main/tooling/fake-api/ocp_deployment/deployment.yaml

2. Create the fake-api service:
oc -n ddosify apply -f https://raw.githubusercontent.com/RHsyseng/ddosify-tooling/main/tooling/fake-api/ocp_deployment/service.yaml

At this point the fake ddosify api will be running inside a pod, the fake api uses json files inside the templates folder as fake results. For the demo, the important file is the symbolic link named latency-test-result-200.json. By default this link is pointing to the global.json results. If you want it to point to a different file you can access the pod and re-link to another json file. For example, if we wanted to get spain.json results we would run the following commands:

oc -n ddosify rsh deployment/ddosify-fakeapi
cd templates/
unlink latency-test-result-200.json
ln -s spain.json latency-test-result-200.json

 
The idea is that you can edit the json file with the results to make the api return the values you want at any point.
Deploy the LatencyCheck Operator
1. Deploy the custom catalogsource
oc apply -f https://raw.githubusercontent.com/RHsyseng/ddosify-tooling/main/tooling/k8soperator/ocp-operator-deployment/CatalogSource.yaml

2.Deploy the latencycheck operator in the ddosify namespace
cat <<EOF | oc -n ddosify apply -f -
---
apiVersion: operators.coreos.com/v1
kind: OperatorGroup
metadata:
  name: latencycheck-operator-operatorgroup
  namespace: ddosify
spec:
  targetNamespaces:
  - ddosify
---
apiVersion: operators.coreos.com/v1alpha1
kind: Subscription
metadata:
  name: latencycheck-operator
  namespace: ddosify
spec:
  channel: "alpha"
  name: latencycheck-operator
  source: telcops-catalog
  sourceNamespace: openshift-marketplace
  startingCSV: latencycheck-operator.v0.0.1
  installPlanApproval: Automatic
EOF

3. Scale down the operator (this operator doesn’t support querying the ddosify fake api server we will be using for the demo)
oc -n ddosify scale deployment latencycheck-controller-manager --replicas 0

4. Deploy the operator with support for ddosify fake api server. Change the FAKE_API_IP var to match your environment.
export FAKE_API_IP=$(oc -n ddosify get svc ddosify-fakeapi -o jsonpath='{.spec.clusterIP}')
curl -sL https://gist.githubusercontent.com/mvazquezc/2061c971029f070fbf2ac36bea23f375/raw/ba491e1e1c9c9bf84d6929a2475462c74c48e911/operator-deployment-fake-api.yaml | sed "s/FAKEAPI_IP/${FAKE_API_IP}/" | oc apply -f -

5. Create the latencycheck
curl -sL https://gist.githubusercontent.com/mvazquezc/2061c971029f070fbf2ac36bea23f375/raw/ba491e1e1c9c9bf84d6929a2475462c74c48e911/latencycheck.yaml | sed "s/DEMO_NAMESPACE/ddosify/g" | oc -n ddosify apply -f -

6. At this point the latencycheck should exist and a placementrule should have been created
oc -n ddosify get placementrule
NAME           AGE   REPLICAS
ddosify-demo   1m   1

Create demo app
1. Deploy the demo files
curl -sL https://gist.githubusercontent.com/mvazquezc/2061c971029f070fbf2ac36bea23f375/raw/6b5ba7955ffbc263c27df284fd8d0c6e7d2346ac/demo-app-files.yaml | sed "s/DEMO_NAMESPACE/ddosify/g" | oc -n ddosify apply -f -

2. Get Latency Measurement Objects 

# Get the object
oc -n ddosify get latencycheck redhat-latencycheck -o yaml
# Get only the results
oc -n ddosify get latencycheck redhat-latencycheck -o jsonpath='{.status.results}' | jq