Adding 'dapr.io/sidecar-listen-addresses' annotation to middleware qu…

…ickstart (#479)

* middleware: adding dapr.io/sidecar-listen-addresses annotation to echoapp deployment and note to readme

* changes after review; adding link to annotation details in the new note

middleware/README.md

@@ -78,6 +78,8 @@ kubectl apply -f deploy/pipeline.yaml
 
 Next, you'll deploy the application and define an ingress rule that routes to the ```-dapr``` service that gets automatically created when you deploy your pod. In this case, all traffic is routed to the Dapr sidecar, which can reinforce various policies through middleware.
 
+>**Note:** 'dapr.io/sidecar-listen-addresses' annotation is added to echoapp deployment to allow external connections. Be cautious of using it in a production environment. To read more on this annotation see [Dapr arguments and annotations for daprd, CLI, and Kubernetes](https://docs.dapr.io/reference/arguments-annotations-overview/)
+
 1. Deploy the application and the ingress rule:
 
 ```bash

middleware/deploy/echoapp.yaml

@@ -18,6 +18,7 @@ spec:
         dapr.io/app-id: "echoapp"
         dapr.io/app-port: "3000"
         dapr.io/config: "pipeline"
+        dapr.io/sidecar-listen-addresses: "0.0.0.0"
     spec:
       containers:
       - name: echo