Canary Releases

This how-to document will show you how to do a canary release of a new sample service. You'll learn how to deploy and onboard a service in TSB, and how to adjust its settings to follow the canary deployment process.

✓ You'll create a workspace and the groups you'll need to onboard the application
✓ Expose the application via an application ingress gateway
✓ Perform the canary release.

Before you get started make sure:

✓ You have a TSB management plane up and running.
✓ You have tctl configured to communicate with the TSB management plane.
✓ The cluster where you are deploying the application to is running a TSB control plane and is correctly onboarded into the TSB management plane.

This guide uses a hello world application, if you're using this in production, please update the relevant fields with the correct information for your application.

Get Started

The following YAML file has three objects - a Workspace for the application, a Gateway group so that you can configure the application ingress, and a Traffic group that will allow you to configure the canary release process. Store it as ws-groups.yaml.

apiVersion: api.tsb.tetrate.io/v2
kind: Workspace
metadata:
  name: helloworld
  organization: tetrate
  tenant: tetrate
spec:
  namespaceSelector:
    names:
    - "*/helloworld"
---
apiVersion: traffic.tsb.tetrate.io/v2
kind: Group
metadata:
  name: helloworld-traffic
  workspace: helloworld
  organization: tetrate
  tenant: tetrate
spec:
  namespaceSelector:
    names:
    - "*/helloworld"
---
apiVersion: gateway.tsb.tetrate.io/v2
kind: Group
metadata:
  name: helloworld-gateway
  workspace: helloworld
  organization: tetrate
  tenant: tetrate
spec:
  namespaceSelector:
    names:
    - "*/helloworld"

Apply with tctl:

tctl apply -f ws-groups.yaml

To deploy your application, start by creating the namespace and enable the Istio sidecar injection.

kubectl create namespace helloworld
kubectl label namespace helloworld istio-injection=enabled

Then deploy your application.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: helloworld-v1
  namespace: helloworld
spec:
  replicas: 1
  selector:
    matchLabels:
      app: helloworld
      version: v1
  template:
    metadata:
      labels:
        app: helloworld
        version: v1
    spec:
      containers:
      - name: hello
        image: "gcr.io/google-samples/hello-app:1.0"
        env:
        - name: "PORT"
          value: "8080"
---
apiVersion: v1
kind: Service
metadata:
  name: helloworld
  namespace: helloworld
spec:
  selector:
    app: helloworld
  ports:
  - protocol: TCP
    port: 443
    targetPort: 8080

Store the file as helloworld.yaml and apply with kubectl:

kubectl apply -f helloworld.yaml

Before you go further, you should ensure that no traffic is accidentally directed to any new version of the application. Then, create a ServiceRoute in the traffic group you created earlier, so that all helloworld traffic is sent solely to version v1 .

apiVersion: traffic.tsb.tetrate.io/v2
kind: ServiceRoute
metadata:
  name: helloworld-canary
  group: helloworld-traffic
  workspace: helloworld
  organization: tetrate
  tenant: tetrate
spec:
  service: helloworld/helloworld.helloworld.svc.cluster.local
  subsets:
  - name: v1
    labels:
      version: v1
    weight: 100

Store the file as serviceroute.yaml and apply with tctl:

tctl apply -f serviceroute.yaml

Great! Now you need to make your application accessible to the world. You need to deploy an ingress gateway for your application and configure it to route the incoming traffic to our application service.

In this example, you're going to expose the application using simple TLS at the gateway. You'll need to provide it with a TLS certificate stored in a Kubernetes secret.

kubectl create secret tls -n helloworld helloworld-certs \
    --cert /path/to/some/helloworld-cert.pem \
    --key /path/to/some/helloworld-key.pem

Now you can deploy your ingress gateway.

apiVersion: install.tetrate.io/v1alpha1
kind: IngressGateway
metadata:
  name: tsb-gateway-helloworld
  namespace: helloworld
spec:
  kubeSpec:
    service:
      type: LoadBalancer

Store the file as hello-ingress.yaml and apply with kubectl:

kubectl apply -f hello-ingress.yaml

The TSB data plane operator in the cluster will pick up this configuration and deploy the gateway's resources in your application namespace. All that is left to do is configure the gateway so that it routes traffic to your application.

apiVersion: gateway.tsb.tetrate.io/v2
kind: IngressGateway
metadata:
  name: helloworld-ingress
  group: helloworld-gateway
  workspace: helloworld
  organization: tetrate
  tenant: tetrate
spec:
  workloadSelector:
    namespace: helloworld
    labels:
      app: tsb-gateway-helloworld
  http:
  - name: helloworld
    port: 443
    hostname: helloworld.tetrate.com
    tls:
      mode: SIMPLE
      secretName: helloworld-certs
    routing:
      rules:
      - route:
          host: helloworld/helloworld.helloworld.svc.cluster.local

Store the file as helloworld-gateway.yaml and apply with tctl:

tctl apply -f helloworld-gateway.yaml

At this point, you can check that your application is reachable by sending an HTTPS request for helloworld.tetrate.com to the gateway service IP.

curl -k -s --connect-to helloworld.tetrate.com:443:$GATEWAY_IP "https://helloworld.tetrate.com/"

Now that your application is running and serving requests, deploy a new version of the application.

apiVersion: apps/v1
kind: Deployment
metadata:
  name: helloworld-v2
  namespace: helloworld
spec:
  replicas: 1
  selector:
    matchLabels:
      app: helloworld
      version: v2
  template:
    metadata:
      labels:
        app: helloworld
        version: v2
    spec:
      containers:
      - name: hello
        image: "gcr.io/google-samples/hello-app:2.0"
        env:
        - name: "PORT"
          value: "8080"

Store the file as helloworld-v2.yaml and apply with kubectl:

kubectl apply -f helloworld-v2.yaml

Since you've created a service route that targets all traffic to version v1. Version v2 won't be getting any requests at this point. Start your canary release by modifying the service route to send 80% of the traffic to our known stable version v1 and 20% to version v2.

apiVersion: traffic.tsb.tetrate.io/v2
kind: ServiceRoute
metadata:
  name: helloworld-canary
  group: helloworld-traffic
  workspace: helloworld
  organization: tetrate
  tenant: tetrate
spec:
  service: helloworld/helloworld.helloworld.svc.cluster.local
  subsets:
  - name: v1
    labels:
      version: v1
    weight: 80
  - name: v2
    labels:
      version: v2
    weight: 20

Store the file as serviceroute-20.yaml and apply with tctl:

tctl apply -f serviceroute-20.yaml

If you keep refreshing your application using your web browser, you'll see a majority of the requests reaching the old v1 version. The other requests will show the output of the new v2 version. To complete the canary release you will need to repeat this last step until all traffic is sent to the new and improved version v2, (or undo and send all traffic back to version v1 if you found some issue with the new version). Simple!