# Canary Deployment

## Requirements

Make sure you have Nginx Ingress deployed on your cluster:

<https://kubernetes.github.io/ingress-nginx/deploy/>

## Deploy app v1

```bash
kubectl create -f - <<EOF

apiVersion: v1
kind: Service
metadata:
  name: my-app-v1
  labels:
    app: my-app
spec:
  ports:
  - name: http
    port: 80
    targetPort: http
  selector:
    app: my-app
    version: v1.0.0
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-app-v1
  labels:
    app: my-app
spec:
  replicas: 1
  selector:
    matchLabels:
      app: my-app
      version: v1.0.0
  template:
    metadata:
      labels:
        app: my-app
        version: v1.0.0
      annotations:
        prometheus.io/scrape: "true"
        prometheus.io/port: "9101"
    spec:
      containers:
      - name: my-app
        image: containersol/k8s-deployment-strategies
        ports:
        - name: http
          containerPort: 8080
        - name: probe
          containerPort: 8086
        env:
        - name: VERSION
          value: v1.0.0
        livenessProbe:
          httpGet:
            path: /live
            port: probe
          initialDelaySeconds: 5
          periodSeconds: 5
        readinessProbe:
          httpGet:
            path: /ready
            port: probe
          periodSeconds: 5

EOF
```

## Deploy ingress for app v1

```bash
kubectl create -f - <<EOF

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: my-app
  labels:
    app: my-app
  annotations:
    kubernetes.io/ingress.class: "nginx"
spec:
  rules:
  - host: my-app.com
    http:
      paths:
      - backend:
          serviceName: my-app-v1
          servicePort: 80

EOF
```

## Deploy app v2

```bash
kubectl create -f - <<EOF

apiVersion: v1
kind: Service
metadata:
  name: my-app-v2
  labels:
    app: my-app
spec:
  ports:
  - name: http
    port: 80
    targetPort: http
  selector:
    app: my-app
    version: v2.0.0
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-app-v2
  labels:
    app: my-app
spec:
  replicas: 1
  selector:
    matchLabels:
      app: my-app
      version: v2.0.0
  template:
    metadata:
      labels:
        app: my-app
        version: v2.0.0
      annotations:
        prometheus.io/scrape: "true"
        prometheus.io/port: "9101"
    spec:
      containers:
      - name: my-app
        image: containersol/k8s-deployment-strategies
        ports:
        - name: http
          containerPort: 8080
        - name: probe
          containerPort: 8086
        env:
        - name: VERSION
          value: v2.0.0
        livenessProbe:
          httpGet:
            path: /live
            port: probe
          initialDelaySeconds: 5
          periodSeconds: 5
        readinessProbe:
          httpGet:
            path: /ready
            port: probe
          periodSeconds: 5

EOF
```

## Deploy ingress canary for app v2

```bash
kubectl create -f - <<EOF

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: my-app-canary
  labels:
    app: my-app
  annotations:
    kubernetes.io/ingress.class: "nginx"

    # Enable canary and send 10% of traffic to version 2
    nginx.ingress.kubernetes.io/canary: "true"
    nginx.ingress.kubernetes.io/canary-weight: "10"
spec:
  rules:
  - host: my-app.com
    http:
      paths:
      - backend:
          serviceName: my-app-v2
          servicePort: 80

EOF
```

Note the following annotations:

```
nginx.ingress.kubernetes.io/canary: "true"
nginx.ingress.kubernetes.io/canary-weight: "10"
```

They ensure only 10% of the traffic will be redirected to this host.

To test run the following command:

```
while sleep 0.1; do curl "PUT-YOUR-NGINX-INGRESS-IP-HERE" -H "Host: my-app.com"; done
```

## Roll out ingress for app v2

First, delete the ingress canary:

```bash
kubectl delete ingress my-app-canary
```

Then roll out the change.

```bash
kubectl create -f - <<EOF

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: my-app
  labels:
    app: my-app
  annotations:
    kubernetes.io/ingress.class: "nginx"
spec:
  rules:
  - host: my-app.com
    http:
      paths:
      - backend:
          serviceName: my-app-v2
          servicePort: 80

EOF
```

## References

<https://medium.com/google-cloud/kubernetes-canary-deployments-for-mere-mortals-13728ce032fe>


---

# Agent Instructions: Querying This Documentation

If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter:

```
GET https://www.devops.buzz/public/kubernetes/deployments/canary-deployment.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.