echo_server_grpc

gRPC echo server

This is a simple Echo server built using Go and gRPC.

Run as docker container

To run the server as a Docker container, follow these steps:

• Change ":9000" to "server:9000" in frontend.go (this is only required for Docker deployments).
• docker build --tag echo-frontend -f Dockerfile-frontend .
• docker build --tag echo-server -f Dockerfile-server .
• docker network create test
• docker run --rm -d --net test -p 9000:9000 --name server echo-server
• docker run --rm -d --net test -p 8080:8080 --name frontend echo-frontend
• curl http://localhost:8080/echo

Push docker container

• Change ":9000" to "echo-server:9000" in frontend.go (this is only required for Kubernetes deployments).
• docker build --tag echo-frontend -f Dockerfile-frontend .
• docker build --tag echo-server -f Dockerfile-server .
• docker tag echo-frontend xzhu0027/echo-frontend-grpc
• docker push xzhu0027/echo-frontend-grpc
• docker tag echo-server xzhu0027/echo-server-grpc
• docker push xzhu0027/echo-server-grpc

How to build and run ACL wasm filter

The ACL Wasm Filter is a content-based Access Control List (ACL) implemented using WebAssembly (Wasm) written in Rust.

• ./build_wasm.sh

  • This will build the ACL wasm written in rust to /tmp/content_based_acl.wasm.

• kubectl apply -f echo-server-grpc-istio-full.yaml

  • This yaml file is generated by istioctl kube-inject -f echo-server-grpc-istio.yaml. It contains the Istio sidecar configuration with a volume that mounts the ACL Wasm Filter into the sidecar container's filesystem.

• kubectl apply -f wasm_acl.yaml

  • Add the ACL wasm filter to echo server. By default, the filter blocks requests that match a certain string.

Note:

• The ACL Wasm Filter can be customized to match different strings or patterns by modifying the lib.rs file.
• You can check the wasm logs use kubectl logs <echo-server-pod-name> -c istio-proxy -f. (Need to use log.warn!)

How to build and run go filter

• ./build_go_filter.sh
• kubectl apply -f echo-server-grpc-istio-full.yaml
• kubectl apply -f wasm_acl.yaml

Note: Go filter is not runnabel yet.. See reference: https://github.com/envoyproxy/envoy/tree/main/examples/golang-http/simple

Acknowledgement

Thanks to the mRPC team for the wasm rust code.