gke-01-rabbitmq.yml

---
apiVersion: apps/v1beta1
kind: Deployment
metadata:
  name: rabbitmq
spec:
  replicas: 1
  template:
    metadata:
      labels:
        app: rabbitmq
    spec:
      restartPolicy: Always
      terminationGracePeriodSeconds: 60
      containers:
        - name: rabbitmq
          image: rabbitmq:3-management
          imagePullPolicy: Always
          ports:
            - containerPort: 5672
            - containerPort: 15672
---
apiVersion: v1
kind: Service
metadata:
  name: rabbitmq
  # => exports env var RABBITMQ_SERVICE_HOST (IP address)
spec:
  type: NodePort
  ports:
    - port: 5672
      name: 'main'
      # => exports env var RABBITMQ_SERVICE_PORT_MAIN=5672
    - port: 15672
      name: 'ui'
      # => exports env var RABBITMQ_SERVICE_PORT_UI=15672
  selector:
    app: rabbitmq

gke-02-env-vars.yml

 env:
   - name: JS_PROXY_URL_PREFIX
     value: "http://$(RENDERTRON_SERVICE_HOST):$(RENDERTRON_SERVICE_PORT)/render/"

gke-03-secret.yml

volumes:
  - name: volume-service-account
    secret:
      defaultMode: 420
      secretName: service-account-for-crawler-deployments
containers:
  - name: crawler-web
    # [...]
    volumeMounts:
      - mountPath: /crawler-secrets
        name: volume-service-account
        readOnly: true
    envFrom:
      - secretRef:
          name: crawler-creds-slack
          optional: true
    env:
    # [...]

gke-04-restart.sh

#!/usr/bin/env bash

echo "ℹ️  This script will stop the crawler, apply db migrations, and then restart the crawler."

MANAGER_IMAGE="latest"
WORKER_REPLICAS=$(kubectl get deployment crawler-worker -o=jsonpath='{$.spec.replicas}')
echo "(i) Found ${WORKER_REPLICAS} worker replicas"

echo "Shutting down crawler-manager, crawler-web and crawler-worker..."
kubectl scale deployment crawler-manager crawler-web crawler-worker --replicas=0

echo "Setting up and running the db-migrate job..."
sed "s,_DOCKER_IMAGE_,${MANAGER_IMAGE},g" ./on-demand/db-migrate.template.yml >./on-demand/db-migrate.yml
./k8s-run-job.sh db-migrate
rm ./on-demand/db-migrate.yml

echo "Restarting crawler-manager, crawler-web and crawler-worker..."
kubectl scale deployment crawler-manager crawler-web --replicas=1
kubectl scale deployment crawler-worker --replicas=${WORKER_REPLICAS}

echo "✅  Done."

gke-05-ingress.yml

apiVersion: extensions/v1beta1
kind: Ingress
metadata:
  name: crawler-ingress
  annotations:
    kubernetes.io/ingress.class: "gce" # we use Google's load balancer for ingress traffic
spec:
  # access thru ip address
  backend:
    serviceName: crawler-web
    servicePort: 8000
  # access thru domain name
  rules:
    - host: crawler.algolia.com
      http:
        paths:
          - backend:
              serviceName: crawler-web
              servicePort: 8000
            path: /*

gke-06-cloudsql.sh

#!/usr/bin/env bash

# This script runs a proxy to give access to our CloudSQL database.
# While it's running, any postgres client (e.g. psql) can connect thru 127.0.0.1:5432.

# Expected inputs:
# - CLOUDSQL_INSTANCE_NAME: e.g. "crawler-pgsql"
# - PGSQL_CREDS_PATH: path where your service account JSON file is stored, e.g. "$HOME/crawler/secrets"
# - PGSQL_CREDS_FILENAME: name of your service account JSON file, e.g. "crawler-pgsql-service-account.json"

if [ -z "$CLOUDSQL_INSTANCE_NAME" ]; then
  echo "missing env var: CLOUDSQL_INSTANCE_NAME (e.g. \"crawler-pgsql\")"; exit 1; fi;

if [ -z "$PGSQL_CREDS_PATH" ]; then
  echo "missing env var: PGSQL_CREDS_PATH (e.g. \"$HOME/crawler/secrets\")"; exit 1; fi;

if [ -z "$PGSQL_CREDS_FILENAME" ]; then
  echo "missing env var: PGSQL_CREDS_FILENAME (e.g. \"crawler-pgsql-service-account.json\")"; exit 1; fi;

GOOGLE_PROJECT="crawler"
ZONE="us-central1"

CLOUDSQL_INSTANCE="$GOOGLE_PROJECT:$ZONE:$CLOUDSQL_INSTANCE_NAME"

echo "Connecting to $CLOUDSQL_INSTANCE thru CloudSQL proxy on 127.0.0.1"
echo "Filepath to service account file: $PGSQL_CREDS_PATH/$PGSQL_CREDS_FILENAME"

docker run -v $PGSQL_CREDS_PATH:/conf -p 127.0.0.1:5432:5432 \
    gcr.io/cloudsql-docker/gce-proxy:1.11 /cloud_sql_proxy \
    -credential_file=/conf/$PGSQL_CREDS_FILENAME \
    -instances=$CLOUDSQL_INSTANCE=tcp:0.0.0.0:5432

These are the code snippets of this article: https://blog.algolia.com/challenging-migration-heroku-google-kubernetes-engine/