Install Istio for Google Cloud Endpoints Services

This document shows how to manually integrate Istio with existing Google Cloud Endpoints services.

Before you begin

If you don’t have an Endpoints service and want to try it out, you can follow the instructions to setup an Endpoints service on GKE. After setup, you should be able to get an API key and store it in ENDPOINTS_KEY environment variable and the external IP address EXTERNAL_IP. You may test the service using the following command:

curl --request POST --header "content-type:application/json" --data '{"message":"hello world"}' "http://${EXTERNAL_IP}:80/echo?key=${ENDPOINTS_KEY}"

You need to install Istio with instructions.

HTTP Endpoints service

1. Inject the service into the mesh using --includeIPRanges by following the instructions so that Egress is allowed to call external services directly. Otherwise, ESP won’t be able to access Google cloud service control.

2. After injection, issue the same test command as above to ensure that calling ESP continues to work.

3. If you want to access the service through Ingress, create the following Ingress definition:

   cat <<EOF | istioctl create -f -
   apiVersion: extensions/v1beta1
   kind: Ingress
   metadata:
     name: simple-ingress
     annotations:
       kubernetes.io/ingress.class: istio
   spec:
     rules:
     - http:
         paths:
         - path: /echo
           backend:
             serviceName: esp-echo
             servicePort: 80
   EOF
   

4. Get the Ingress IP through instructions. You can verify accessing the Endpoints service through Ingress:

   curl --request POST --header "content-type:application/json" --data '{"message":"hello world"}' "http://${INGRESS_HOST}:80/echo?key=${ENDPOINTS_KEY}"i
   

HTTPS Endpoints service using secured Ingress

The recommended way to securely access a mesh Endpoints service is through an ingress configured with mutual TLS.

1. Expose the HTTP port in your mesh service. Adding "--http_port=8081" in the ESP deployment arguments and expose the HTTP port:

     - port: 80
    targetPort: 8081
    protocol: TCP
    name: http
   

   Update the mesh service deployment.

2. Turn on mTLS in Istio by using the following command:

   kubectl edit cm istio -n istio-system
   

   And uncomment the line:

   authPolicy: MUTUAL_TLS
   

3. After this, you will find access to EXTERNAL_IP no longer works because istio proxy only accept secure mesh connections. Accessing through Ingress works because Ingress does HTTP terminations.

4. To secure the access at Ingress, following the instructions.

5. You can verify accessing the Endpoints service through secure Ingress:

   curl --request POST --header "content-type:application/json" --data '{"message":"hello world"}' "https://${INGRESS_HOST}/echo?key=${ENDPOINTS_KEY}" -k
   

HTTPS Endpoints service using LoadBalancer EXTERNAL_IP

This solution uses Istio proxy for TCP bypassing. The traffic is secured through ESP. This is not a recommended way.

1. Modify the name of the HTTP port to be tcp

     - port: 80
    targetPort: 8081
    protocol: TCP
    name: tcp
   

   Update the mesh service deployment. See further readings on port naming rules here.

2. You can verify access to the Endpoints service through secure Ingress:

   curl --request POST --header "content-type:application/json" --data '{"message":"hello world"}' "https://${EXTERNAL_IP}/echo?key=${ENDPOINTS_KEY}" -k
   

What next?

Learn more about GCP Endpoints.