@egodigital/microservices

@egodigital/microservices

Shared library for microservices, written for Node.js, in TypeScript.

Install

Execute the following command from your project folder, where your package.json file is stored:

npm install --save @egodigital/microservices

Usage

Auth

Passwords

Hash passwords with bcrypt:

import { checkPassword, checkPasswordSync, hashPassword, hashPasswordSync } from '@egodigital/microservices';

const hash1 = await hashPassword('test');
const matches2 = await checkPassword('test', hash1);

const hash2 = hashPasswordSync('test');
const matches2 = checkPasswordSync('test', hash2);

JWT

Sign and verify JSON Web Tokens:

import { signJWT, verifyJWT } from '@egodigital/microservices';

interface IUserToken {
    uuid: string;
}

const jwt = signJWT({
    uuid: 'cb246b52-b8cd-4916-bfad-6bfc43845597'
});

const decodedToken = verifyJWT<IUserToken>(jwt);

Express

Use predefined Express middleware to verify and decode JWTs:

import express from 'express';
import { withJWT } from '@egodigital/microservices';

const app = express();

app.get('/', withJWT(), async (request, response) => {
    // decoded, valid user token is stored in:
    // request.userToken
});

app.listen(4242, () => {
    console.log('Service is listening ...');
});

Constants

Name	Description	Example
BCRYPT_ROUNDS	The number of rounds for bcrypt hashing. Default: 10	12
JWT_SECRET	The secret for signing and validating JWT.	mySecretJWTSecret
NATS_CLUSTER_ID	The name of the cluster, that contains all microservices.	my-cluster
NATS_GROUP	The name of the pod group / Kubernetes deployment.	my-service-or-deployment
NATS_URL	The URL to the NATS server.	http://my-nats-service:4222
POD_NAME	The name of the pod. This should come as imported metadata from Kubernetes.	my-service-or-deployment-xcsgbxv

NATS

Connect to a NATS server:

import { stan } from '@egodigital/microservices';

await stan.connect();
stan.exitOnClose();

Listener

Listen for events:

import { NatsListener } from '@egodigital/microservices';

interface IMyEvent {
    foo: string;
    bar: number;
}

const myEventListener = new NatsListener<IMyEvent>('my.event');

myEventListener.onMessage = async (context) => {
    // handle message in context.message of type IMyEvent
};

myEventListener.listen();

Publisher

Publish events:

import { NatsPublisher } from '@egodigital/microservices';

interface IMyEvent {
    foo: string;
    bar: number;
}

const myEventPublisher = new NatsPublisher<IMyEvent>('my.event');

await myEventPublisher.publish({
    foo: "TM+MK",
    bar: 42
});

Documentation

The API documentation can be found here.

Changelog

0.4.1

• better error handling of onMessage listener