support generate method invoke template

[qsLI]

trafficstars

Although we can compse request param step by step，it would be more convenient if grpcurl can generate it automately.

traditionally

step 1

➜  ~ grpcurl localhost:20789 describe grpc.health.v1.Health.Check
grpc.health.v1.Health.Check is a method:
rpc Check ( .grpc.health.v1.HealthCheckRequest ) returns ( .grpc.health.v1.HealthCheckResponse );

➜  ~ grpcurl localhost:20789 describe .grpc.health.v1.HealthCheckRequest
grpc.health.v1.HealthCheckRequest is a message:
message HealthCheckRequest {
  string service = 1;
}

then make the request json, and invoke :

➜  ~ grpcurl -d '{"service": "test"}'  localhost:20789 grpc.health.v1.Health/Check
{
  "status": "SERVING",
  "idle": 0.5,
  "max_thread_count": 24
}

newly

Suppose we support template command, and template will generate a invoke template

➜  ~ grpcurl localhost:20789 template grpc.health.v1.Health.Check
grpcurl -d '{"service": "test"}'  localhost:20789 grpc.health.v1.Health/Check