6.6. Interacting with a serverless application using HTTP2 and gRPC

Procedure

1. Find the application host. See the instructions in Verifying your serverless application deployment.

2. Find the ingress gateway’s public address:

   $ oc -n knative-serving-ingress get svc kourier

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   NAME                   TYPE           CLUSTER-IP      EXTERNAL-IP                                                             PORT(S)                                                                                                                                      AGE
   kourier   LoadBalancer   172.30.51.103   a83e86291bcdd11e993af02b7a65e514-33544245.us-east-1.elb.amazonaws.com   80:31380/TCP,443:31390/TCP   67m

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   The public address is surfaced in the EXTERNAL-IP field. In this case, it would be a83e86291bcdd11e993af02b7a65e514-33544245.us-east-1.elb.amazonaws.com.

3. Manually set the host header of your HTTP request to the application’s host, but direct the request itself against the public address of the ingress gateway.

   The following example uses the information obtained from the steps in Verifying your serverless application deployment:

   Example command

   $ curl -H "Host: hello-default.example.com" a83e86291bcdd11e993af02b7a65e514-33544245.us-east-1.elb.amazonaws.com

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   Example output

   Hello Serverless!

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   You can also make a gRPC request by setting the authority to the application’s host, while directing the request against the ingress gateway directly:

   grpc.Dial(
       "a83e86291bcdd11e993af02b7a65e514-33544245.us-east-1.elb.amazonaws.com:80",
       grpc.WithAuthority("hello-default.example.com:80"),
       grpc.WithInsecure(),
   )

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   注意

   Ensure that you append the respective port, 80 by default, to both hosts as shown in the previous example.