andywer

import Koa from "koa"
import * as KoaHAL from "$new-hal-koa-package"
import { api, Users } from "./hal"

const app = new Koa()

const koaRouter = KoaHAL.Router(api, router => {
  // GET /users
  router.get(Users, async ctx => {
    const users = await queryAllUsers()

andywer

Overall Approach

This document is a short description of the monorepo setup that I came up for a few different smaller projects in the last 8 months or so.

Directory structure

/
  services/
 product/

andywer

import { Responses as PublisherAPIResponses } from "@satoshipay/publisher-service-api"
import axios from "axios"
import { URL } from "url"
import config from "../config"

export async function getPublisherById (id: string) {
  const url = new URL(`/${id}`, config.publisherServiceUrl).toString()
  return await axios.get(url) as PublisherAPIResponses["GET /*"]
}

andywer

import { createApp, respond, route } from "koax"
import pkg from "../package.json"

const app = createApp()

app.get("/", async () => {
  const body = {
    name: pkg.name,
    version: pkg.version
  }

andywer

Keybase proof

I hereby claim:

• I am andywer on github.
• I am andywer (https://keybase.io/andywer) on keybase.
• I have a public key ASAaseoxu8cFB_1LgQKirVmIAnK46TA20OoMraS114BRwAo

To claim this, I am signing this object:

andywer

/*
 * Description:
 *
 * There are times when we want to re-use some data created/derived in a middleware later in a route handler.
 *
 * The default Koa way of doing so would be using `context.state`. Unfortunately `context.state` is hard to type and
 * quite implicit, since it's an object shared and potentially mutated by all middlewares and the route handler.
 */

/*

andywer

let lastLoggingTime = Date.now();

function logUpdate (componentName, update, stateBefore, stateAfter, stack) {
  const msSinceLastPrint = Date.now() - lastLoggingTime;

  console.groupCollapsed(
    `%c<${componentName}> setState: %o %c%s`,
    "color: #5080ff",
    update,
    "color: #808080",

andywer

type Arguments<T> = [T] extends [(...args: infer U) => any]
  ? U
  : [T] extends [void] ? [] : [T]

/**
 * Type-safe event emitter.
 *
 * Use it as:
 *
 * interface MyEvents {

andywer

Service federation

• Each node has a key pair to authenticate itself to its peers
  • Key pair might or might not relate to a Stellar account
• Each node provides a SSE co-signature request streaming endpoint other peers or wallets may subscribe to
• When connecting to another peer
  • Subscribe to that peer's stream
  • Post a message to invite the peer to subscribe to the node's stream
• Each node exposes a list of the peers that it is connected to
• Each node has a configurable set of trusted peers, will always connect to them and accept them subscribing

andywer

Stellar Multisig Coordination Service

Objective

SEP-0007 introduced a standard for payment requests (basically templated transactions) on Stellar. In order to provide a smooth user experience when working with multi-signature accounts, wallets need to be able to send each other realtime payment requests.

That requires a new kind of service in the Stellar eco system: A multi-signature coordination service.