TypeScript gRPC health check client

health_check_client.ts

// https://github.com/grpc/grpc-node/tree/master/packages/grpc-health-check
import { service as healthServiceDefinition } from 'grpc-health-check';

// https://github.com/grpc/grpc-node/tree/master/packages/grpc-js
import { credentials, makeClientConstructor } from '@grpc/grpc-js';

const HealthClientConstructor = makeClientConstructor(healthServiceDefinition, 'grpc.health.v1.HealthService');
const serverAddress = '0.0.0.0:50051';
const healthClient = new HealthClientConstructor(serverAddress, credentials.createInsecure());

const main = () => {
  console.log(`Starting health check on ${serverAddress}`);

  healthClient.check({service: ''}, (error: Error, value: string) => {
    if (error) {
      console.error(`Error checking health: ${error.message}`);
      process.exit(1);
    }
    console.log(value);
    process.exit(0);
  });
}

main();