echogen

echogen

echogen is a util for generating Kubernetes manifests from echo configurations.

Overview

Installation

go install istio.io/istio/pkg/test/framework/components/echo/echogen

Usage

echogen [opts] config.yaml

The config file is YAML containing a list of echo.Config objects:

- Service: a
  Namespace: echo
- Service: headless
  Namespace: echo
  Headless: true

Options

echogen supports all options from the test framework that would affect Echo deployments such as: istio.test, .imagePullSecret, istio.test.hub and several others.

In addition to the framework level options:

-out <file>: Write output to the specified file
-dir: If specified, each deployment will be written to a separate file, in a directory named by -out.

Full Example with gRPC UI

1. Make sure to install gRPC UI if you haven't already

2. Create an echogen config:

echo '
- Service: a
  Namespace: echo
- Service: b
  Namespace: echo
' > config.yaml

1. Run echogen:

echogen -out echo.yaml config.yaml

1. Apply the manifest to the cluster

kubectl apply -f echo.yaml

1. Port-forward the gRPC port (default container port is 17070)

kubectl -n echo port-forward a-v1-fc649d9fc-59rkj 17070

1. Start gRPC UI

grpcui -plaintext localhost:17070

1. Because our echo gRPC service enables reflection, you should be able to open your browser and get a user interface that shows all of the possible methods and request options.

   Change the "Method name" to ForwardEcho, then in "Request Data" set url to grpc://b:7070 then click Invoke

2. (Bonus) If you open the "Raw Request (JSON)" tab, you can re-use that for requests via grpcurl without constructing JSON by hand:

grpcurl -plaintext localhost:17070 EchoTestService/ForwardEcho -d '{"url": "grpc://b:7070"}'