Getting Started

Your business logic can be written in many languages. One of them is Javascript or Typescript using the Node.js ecosystem.

To simplify the creation of a micro-executor based on node.js, an SDK is available that contains everything necessary.

Prerequisites

Before jumping into development, make sure you have the following tools at your disposal:

• Node.js
• NPM
• Javascript/Typescript IDE: VSCode, WebStorm, Sublime Text...

Getting Started

Create a new Node.js project using NPM.

# Create project folder
mkdir [PROJECT_FOLDER]

# Positioning inside project folder
cd [PROJECT_FOLDER]

# Init Node.js project
npm init

Install SDK:

npm i @sme.up/kokos-sdk-node

Now open the project with your favorite IDE.

Update package.json, add the following config:

package.json

{
  ...
  "type": "module",
  "scripts": {
    "clean": "rimraf lib",
    "build": "npm run clean && tsc",
    "test": "NODE_ENV=test jest",
    "dev": "NODE_ENV=development nodemon --watch './**/*.ts' --exec node --experimental-specifier-resolution=node --loader ts-node/esm ./src/index.ts",
    "start": "NODE_ENV=production node ./lib/index.js",
    "test:win": "SET NODE_ENV=test&&jest",
    "dev:win": "SET NODE_ENV=development&&nodemon --watch . -e ts --exec \"node --experimental-specifier-resolution=node --loader ts-node/esm ./src/index.ts\"",
    "start:win": "SET NODE_ENV=production&&node ./lib/index.js",
  ...
}

warning

NB: [command]:win identifies the command for Windows.

Create tsconfig.json file:

tsconfig.json

{
  "compilerOptions": {
    "module": "ESNext",
    "target": "ESNext",
    "outDir": "./lib",
    "baseUrl": "./src",
    "rootDir": "./src",
    "moduleResolution": "node",
    "alwaysStrict": true,
    "strict": true,
    "noImplicitAny": true,
    "experimentalDecorators": true,
    "emitDecoratorMetadata": true,
    "esModuleInterop": true,
    "declaration": true,
    "sourceMap": true
  },
  "include": ["src/**/*.ts"],
  "exclude": ["node_modules", "lib", "**/*.test.ts"]
}

Create src/index.ts file:

import { startServer } from "@sme.up/kokos-sdk-node";

startServer(MICRO_EXECUTOR_ID);

info

MICRO_EXECUTOR_ID is the unique ID of your micro-executor.

The naming convention should be: "me-{language}-{company}-{usecase}", with -{usecase} being optional.

For example, a micro-executor written in Node.js for the company Smeup that handles billing should be called "me-node-smeup-billing"

Create a sample KokosService in src/services/HELLO_WORLD.ts:

import {
  ExecutionContext,
  Fun,
  KokosService,
  SmeupDataStructureWriter,
} from "@sme.up/kokos-sdk-node";

const HELLO_WORLD: KokosService = {
  methods: {
    "HLL.WRL": helloWorld,
  },
};

async function helloWorld(
  _fun: Fun,
  _context: ExecutionContext,
  printer: SmeupDataStructureWriter
) {
  printer.writeDataNode({
    children: [],
    obj: {
      t: "",
      p: "",
      k: "",
    },
    value: "Hello World",
  });
}

export default HELLO_WORLD;

Run application:

# Linux
npm run dev

# Windows
npm run dev:win

Try to execute FUN using swagger execute fun api (http://localhost:8011/swagger/#/execution/ExecuteFun)

Add the following payload:

{
  "fun": {
    "component": "TRE",
    "service": "HELLO_WORLD",
    "function": "HLL.WRL"
  },
  "context": {
    "user": {
      "sessionId": "",
      "username": "",
      "environment": "",
      "device": ""
    }
  }
}