183-keda.sh

# Source: https://gist.github.com/2dad051fe41bd2bbcf94eda74386ce49

#############################################
# KEDA: Kubernetes Event-Driven Autoscaling #
# https://youtu.be/3lcaawKAv6s              #
#############################################

# Additional Info:
# - KEDA: https://keda.sh
# - Robusta: https://robusta.dev
# - Kubernetes Notifications, Troubleshooting, And Automation With Robusta: https://youtu.be/2P76WVVua8w
# - The Best Performance And Load Testing Tool? k6 By Grafana Labs: https://youtu.be/5OgQuVAR14I

#########
# Setup #
#########

# Create a Kubernetes cluster

# The Gist was NOT tested with local Kubernetes cluster (e.g., minikube, Rancher Desktop, etc.).
# Some changes might be required

helm repo add traefik \
    https://helm.traefik.io/traefik

helm repo update

helm upgrade --install traefik traefik/traefik \
    --namespace traefik --create-namespace --wait

# If NOT EKS
export INGRESS_HOST=$(kubectl --namespace traefik \
    get svc traefik \
    --output jsonpath="{.status.loadBalancer.ingress[0].ip}")

# If EKS
export INGRESS_HOSTNAME=$(kubectl --namespace traefik \
    get svc traefik \
    --output jsonpath="{.status.loadBalancer.ingress[0].hostname}")

# If EKS
export INGRESS_HOST=$(dig +short $INGRESS_HOSTNAME)

echo $INGRESS_HOST

# Repeat the `export` command(s) if the output is empty.

# If the output contains more than one IP, wait for a while longer, and repeat the `export` commands.

# If the output continues having more than one IP, choose one of them and execute `export INGRESS_HOST=[...]` with `[...]` being the selected IP.

git clone https://github.com/vfarcic/keda-demo

cd keda-demo

# Install `yq` from https://github.com/mikefarah/yq if you do not have it already
yq --inplace \
    ".spec.rules[0].host = \"dot.$INGRESS_HOST.nip.io\"" \
    k8s/ing.yaml

cat k6.js \
    | sed -e "s@http\.get.*@http\.get('http://dot.$INGRESS_HOST.nip.io');@g" \
    | tee k6.js

cat k6-100.js \
    | sed -e "s@http\.get.*@http\.get('http://dot.$INGRESS_HOST.nip.io');@g" \
    | tee k6-100.js

kubectl create namespace production

kubectl --namespace production \
    apply --filename k8s/

helm repo add kedacore \
    https://kedacore.github.io/charts

helm repo add robusta \
    https://robusta-charts.storage.googleapis.com

helm repo add prometheus-community \
    https://prometheus-community.github.io/helm-charts

helm repo update

helm install keda kedacore/keda \
    --namespace keda \
    --create-namespace \
    --wait

helm upgrade --install \
    prometheus prometheus-community/prometheus \
    --namespace monitoring \
    --create-namespace \
    --wait

# Execute only if you do not already have Robusta CLI
pip install -U robusta-cli --no-cache

robusta gen-config

# Follow the instructions from the Wizard
# Do NOT choose to install Prometheus (it's already installed)

helm upgrade --install robusta robusta/robusta \
    --namespace monitoring --create-namespace \
    --values generated_values.yaml \
    --values robusta-values.yaml \
    --set clusterName=dot --wait

#######################################
# Auto-Scaling Applications With KEDA #
#######################################

echo "http://dot.$INGRESS_HOST.nip.io"

# Open it in a browser

kubectl --namespace production \
    get pods

cat keda-prom.yaml

kubectl --namespace production apply \
    --filename keda-prom.yaml

k6 run k6.js

cat robusta-values.yaml

kubectl --namespace production \
    get pods,hpa,scaledobjects

cat k6-100.js

k6 run k6-100.js

kubectl --namespace production \
    get pods,hpa,scaledobjects

kubectl --namespace production \
    get pods,hpa,scaledobjects

cat keda-prom.yaml

# Open https://keda.sh/docs/scalers/

# Open https://github.com/knative-sandbox/eventing-autoscaler-keda

###########
# Destroy #
###########

# Destroy or reset the cluster

It is missing the helm repo for prometheus. I have forked it and added the prometheus-community repository, plus amended the helm install to use the chart provided by the prometheus-community repo.
If you want you can update this gist using https://gist.github.com/fernandojimenez-lk/793ea2222a2aba617a7c5150ae7cb8ba

Good catch. Thanks for that.

Gist is updated :)

@vfarcic I'm seeing the following when attempting to install Traefik into local K8s cluster using MiniKube:

➜ helm upgrade --install \
    traefik traefik/traefik \
    --namespace traefik \
    --create-namespace \
    --wait
Release "traefik" does not exist. Installing it now.

Error: timed out waiting for the condition

Then I ran it again and received a different error:

➜ helm upgrade --install \
    traefik traefik/traefik \
    --namespace traefik \
    --create-namespace \
    --wait
Error: UPGRADE FAILED: timed out waiting for the condition

Do you have any ideas as to why this may be happening?

After some research, it seems that one needs to use a compatible version of Helm for the K8s version. BTW, I was trying to use the K8s 1.26.0 cluster with Helm v3.10.3. Thus, others may find the following link helpful:

https://helm.sh/docs/topics/version_skew

However, making this change (i.e. downgrading to K8s 1.25.5) doesn't resolve the issue for me.

I'm not sure whether Traefik works with Minikube. It probably does but you might need to tweak some parameters. My best guess is that the Service type should be changed from LoadBalancer to NodePort. Local Kubernetes clusters tend to be tricky with Ingresses and the easiest option is often to use the one that is baked into it. With Minikube, I believe that's NGINX Ingress. I haven't used Minikube for a long while now so I might be wrong though.

Anyways... The best option on Minikube might be to drop Traefik altogether and use NGINX Ingress (I think it's a Minikube plugin). If you do that, you might need to change a few commands that export INGRESS_HOST (I think it would be 127.0.0.1 but I might be wrong on that one).

Finally, if you stick with Traefik in Minikube, remove --wait from the helm command. That will skip waiting for all the resources to be healthy and you can see what's the issue with Traefik. Start with kubectl --namespace traefik get all,ingresses.

@vfarcic Thanks for getting back to me and I appreciate it. Anyway, I just ended up creating a K8s cluster on Linode that worked as expected with one minor tweak:

changed

helm upgrade --install \
    robusta robusta/robusta \
    --namespace monitoring \
    --create-namespace \
    --values generated_values.yaml \
    --values robusta-values.yaml \
    --wait

to

helm upgrade --install \
    robusta robusta/robusta \
    --namespace monitoring \
    --create-namespace \
    --values generated_values.yaml \
    --values robusta-values.yaml \
    --set clusterName=<CLUSTER_NAME> \
    --wait

Otherwise, I was getting an error saying that I was missing the cluster name.

I'm glad it worked out.

Something must have changed in Robusta so that the clusterName is now required. Thanks for letting me know. The Gist has been updated...