How to create a new `JoeDemoService` backend service in 7 easy steps...

script.md

Node GRPC Demo Script

How to create a new JoeDemoService backend service in 7 easy steps...

1. Create new thrift file in ~/development/urbancompass/src/thrift/urbancompass/joe_demo:

namespace go joe_demo.joe_demo_service
namespace java com.urbancompass.joe_demo
namespace js joe_demo.joe_demo_service
namespace py gen.urbancompass.joe_demo.joe_demo_service

include "common/base.thrift"

struct JoeDemoRequest {
  1: optional string msg;
}

struct JoeDemoResponse {
  1: optional string msg;
  2: optional base.ResponseStatus status;
}

service JoeDemoService extends base.BaseService {
  JoeDemoResponse foo(1: JoeDemoRequest request)
    (api.url = "/joe_demo", api.method = "GET");
} (api.url = "/joe_demo")

2. Re-build local apiv3 with new thrift and start it pointing to new service at 127.0.0.1:1337:

./scripts/go install compass.com/api/cmd/apid && \
  ./build-support/go/bin/apid --joe-demo-service=grpc://127.0.0.1:1337

3. Scaffold out a new grpc NodeJS app

cd ~/development/uc-node-services
./scripts/initService.sh

4. Generate typescript thrift from local thrift directory

cd ~/uc-node-services/services/grpc-joe-demo
pnpm start gen-thrift.local

5. Update service Node service implementation to implement JoeDemoService

import * as grpc from 'grpc';

import {ServiceHealth, ServiceStatus, SystemHealth, EchoRequest, EchoResponse} from '../thrift-gen/ts/common/base';

import {JoeDemoRequest, JoeDemoResponse} from '../thrift-gen/ts/joe_demo/joe_demo_service';
import {createJoeDemoServiceImplementation, JoeDemoServiceDefinition} from '../thrift-gen/ts/joe_demo/joe_demo_service/JoeDemoService__grpc';

const implementation = createJoeDemoServiceImplementation({
  foo(request: JoeDemoRequest) {
    console.log('JoeDemoRequest', request);

    return new JoeDemoResponse({
      msg: request.msg === 'foo' ? 'bar' : 'Hello World!',
    });
  },

  getServiceHealth(): ServiceHealth | Promise<ServiceHealth> {
    return new ServiceHealth({
      name: 'GrpcJoeDemoService',
      status: ServiceStatus.OK,
      statusDetails: 'Service is okay',
    });
  },

  getSystemHealth(): SystemHealth | Promise<SystemHealth> {
    return new SystemHealth({
      overallStatus: ServiceStatus.OK,
      serviceName: 'GrpcJoeDemoService',
      subsystemsStatus: [],
    });
  },

  echo(request: EchoRequest): EchoResponse | Promise<EchoResponse> {
    return new EchoResponse({
      request,
    });
  },
});

const server = new grpc.Server();
server.addService(JoeDemoServiceDefinition, implementation);
server.bind('127.0.0.1:1337', grpc.ServerCredentials.createInsecure());
server.start();

console.log('Server started at 127.0.0.1:1337');

6. Start the nodejs service, pointing to local thrift

pnpm start dev

7. Send the service traffic via apiv3

curl 'http://127.0.0.1:4000/joe_demo'
curl 'http://127.0.0.1:4000/joe_demo?msg=foo'