Tornado - Demo Websockets App

This is a sample application that demonstrates the use of an upgraded websockets connection on an ingress traffic when using Istio VirtualService. The app.yaml creates a Kubernetes Service and a Deployment that is based on an existing Docker image for Hiroakis's Tornado Websocket Example.

Notice: The addition of websockets upgrade support in v1alpha3 routing rules has only been added after the release of Istio v0.8.0.

Prerequisites

Install Istio by following the Istio Quick Start.

Installation

1. First install the application service:

   • With manual sidecar injection:

   kubectl create -f <(istioctl kube-inject -f samples/websockets/app.yaml)
   

   • With automatic sidecar injection

   kubectl create -f samples/websockets/app.yaml
   

2. Create the Ingress Gateway and VirtualService that enables the upgrade to Websocket for incoming traffic:

   kubectl create -f samples/websockets/route.yaml
   

Test

• Find your ingress gateway IP

• Access http://$GATEWAY_IP/ with your browser

• The WebSocket status should show a green open status which means that a websocket connection to the server has been established. To see the websocket in action see the instructions in the REST API examples section of the demo app webpage for updating the server-side data and getting the updated data through the open websocket to the table in the webpage (without refreshing).

Cleanup

kubectl delete -f samples/websockets/route.yaml
kubectl delete -f samples/websockets/app.yaml