grpc.proxy

grpc.proxy

Listens on https port 9090 and will echo back whatever is published to grpc_echo on tcp port 8080.

Requirements

• bash, jq, nc, grpcurl
• Kubernetes (e.g. Docker Desktop with Kubernetes enabled)
• kubectl
• helm 3.0+

Build grpc-echo service

$ docker build -t zilla-examples/grpc-echo:latest .
 => exporting to image
  => => exporting layers
 => => writing image sha256:8ad3819be40334045c01d189000c63a1dfe22b2a97ef376d0c6e56616de132c7 
 => => naming to docker.io/zilla-examples/grpc-echo:latest

Setup

The setup.sh script:

• installs Zilla to the Kubernetes cluster with helm and waits for the pod to start up
• starts port forwarding

$ ./setup.sh
docker image inspect zilla-examples/grpc-echo:latest --format 'Image Found {{.RepoTags}}'

+ helm install zilla-grpc-proxy chart --namespace zilla-grpc-proxy --create-namespace --wait --timeout 2m
NAME: zilla-grpc-proxy
LAST DEPLOYED: Tue Apr 18 14:46:24 2023
NAMESPACE: zilla-grpc-proxy
STATUS: deployed
REVISION: 1
TEST SUITE: None
+ kubectl port-forward --namespace zilla-grpc-proxy service/zilla 9090
+ nc -z localhost 9090
+ kubectl port-forward --namespace zilla-grpc-proxy service/grpc-echo 8080
+ sleep 1
+ nc -z localhost 9090
Connection to localhost port 9090 [tcp/websm] succeeded!
+ nc -z localhost 8080
Connection to localhost port 8080 [tcp/http-alt] succeeded!

Verify behavior

Echo one message via unary rpc.

grpcurl -insecure -proto chart/files/proto/echo.proto  -d '{"message":"Hello World"}' localhost:9090 example.EchoService.EchoUnary

{
  "message": "Hello World"
}

Echo each message via bidirectional streaming rpc.

grpcurl -insecure -proto chart/files/proto/echo.proto -d @ localhost:9090 example.EchoService.EchoBidiStream

{
  "message": "Hello World"
}
{
  "message": "Hello World"
}

{
  "message": "Hello World"
}
{
  "message": "Hello World"
}

Teardown

The teardown.sh script stops port forwarding, uninstalls Zilla and deletes the namespace.

$ ./teardown.sh
+ pgrep kubectl
24494
24495
+ killall kubectl
+ helm uninstall zilla-grpc-proxy --namespace zilla-grpc-proxy
release "zilla-grpc-proxy" uninstalled
+ kubectl delete namespace zilla-grpc-proxy
namespace "zilla-grpc-proxy" deleted