hawkly-grpc

hawkly gRPC wrapper for javascript

Repository | npm

** Work in progress **

This is a wrapper around gRPC to add opentracing and async/await.

Usage

Server

Client

We provide a wrapper for the grpc client (based on a rewrite of https://www.npmjs.com/package/grpc-caller), which will automatically create a span and add it's context to the outgoing grpc call.

To create a client you need to pass options to instantiate both the Hawkly Tracer and the grpc client.

import {
  // Use this to create a new gRPC client from a proto file
  // This lets you call the services defined in the proto file
  createClient,
} from 'hawkly-grpc';

// defince your proto path
const PROTO_PATH: string = __dirname + '/helloworld.proto';

// create the client and tracer
const { tracer, client } = createClient(
  {
    // hawkly
    accessToken: 'get your token from hawkly.io',
    componentName: 'myComponent',
    // grpc
    host: grpcHost,
    proto: PROTO_PATH,
    name: 'Greeter',
  },
);

  // Create a new span to cover this unit of work
  const span: any = tracer.startSpan('myFirstSpan');

  // await the result of our gRPC call to `sayHello`
  // and an object of options to the call to specify the arg etc
  const request:Promise<any> = await client.sayHello({
    arg: { name: grpcHost },
    // pass the span we just created
    span,
  });

  // do stuff with result

  // finish our span
  span.finish();

Get the request Span

If you need access to the Span created for the request, you can pass in requestSpan:true to the options of the call. This will return you a tuple with request as a Promise and requestSpan and span as the span (both exist so you can use destructuring without having a local variable conflict with span).

import {
  // Use this to create a new gRPC client from a proto file
  // This lets you call the services defined in the proto file
  createClient,
  // request interface type
  TracedUnaryRequest,
} from 'hawkly-grpc';

  // await the result of our gRPC call to `sayHello`
  // and an object of options to the call to specify the arg etc
  const {request, requestSpan}:TracedUnaryRequest = await client.sayHello({
    arg: { name: grpcHost },
    // pass the span we just created
    span,
    requestSpan: true,
  });
  const result:any = await request;

More information

http://www.grpc.io/

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hawkly.io Owen Kelly