/x/grpc_basic

⚠️ You probably should wait for more mature and standard aligned implementation beacuse:

1. This lib doesn’t use Deno’s 1.9 HTTP/2 native bindings, but relies on JS implementation roughly ported from node-http2
2. I’m not an expert in gRPC or HTTP/2, I just moved HTTP/2 frames around until it worked
3. It was never meant for production use, only for fun and some integration tests and scripts
4. I have no plans on implementing full gRPC spec

goals - keep it simple

• load proto files
• server unary calls
• client unary calls
• errors
• server server streams
• client server streams
• context deadlines
• multiplex calls
• calls metadata
• logging

todo

• remove all deno/node compatibility (Buffer, stream.Transform, etc)
• acquire more knowledge about http2 frames

maybe goals

• *.d.ts client/service codegen
• builtin retries

non goals - gRPC bloat

• no TLS
• no client streams
• no bidirectional streams
• no load balancers (maybe simple helper for proxy lb)
• no interceptors (revisit this later)

hello world

greeter.proto

syntax = "proto3";

package prohazko;

service Greeter {
  rpc SayHello (HelloRequest) returns (HelloReply) {}
}

message HelloRequest {
  string name = 1;
}

message HelloReply {
  string message = 1;
}

greeter.d.ts (generated (maybe))

export interface Greeter {
  SayHello(request: HelloRequest): Promise<HelloReply>;
}

export interface HelloRequest {
  name?: string;
}

export interface HelloReply {
  message?: string;
}

server.ts

⚠️ API will soon be changed to more Golang-ish

s := grpc.NewServer()
pb.RegisterGreeterServer(s, &server{})

import { delay } from "https://deno.land/std@0.94.0/async/delay.ts";
import { GrpcService } from "https://deno.land/x/grpc_basic@0.2.7/server.ts";
import { Greeter } from "./greeter.d.ts";

const port = 15070;
const root = await Deno.readTextFile("./greeter.proto");

const svc = new GrpcService<Greeter>(root, {
  async SayHello({ name }) {
    await delay(50);
    return { message: `hello ${name || "world"}` };
  },
});

console.log(`gonna listen on ${port} port`);
for await (const conn of Deno.listen({ port })) {
  await svc.handle(conn);
}

client.ts

import { getClient } from "https://deno.land/x/grpc_basic@0.2.7/client.ts";
import { Greeter } from "./greeter.d.ts";

const client = getClient<Greeter>({
  port: 15070,
  root: await Deno.readTextFile("./greeter.proto"),
  serviceName: "Greeter",
});

const { message } = await client.SayHello({ name: "oleg" });
console.log(message);

client.close();