proxy

1. grpc proxy
2. http proxy

grpc proxy

1. examples/grpc_hello

2. examples/grpc_router

   1. go install github.com/lengzhao/proxy/examples/grpc_router@latest
   2. add conf.json in dir

   {
       "route":{
           "helloworld.Greeter":"127.0.0.1:50051"
       }
   }

   1. run router: grpc_router

3. examples/http_proxy

   1. go install github.com/lengzhao/proxy/examples/http_proxy@latest
   2. run proxy: ./http_proxy
   3. set http proxy to 127.0.0.1:8081