@egomobile/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 @egomobile/microservices

Usage

Auth

Passwords

Hash passwords with bcrypt:

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

const hash1 = await hashPassword('test');
const doesMatch1 = await checkPassword('test', hash1);  // true

const hash2 = hashPasswordSync('test');
const doesMatch2 = checkPasswordSync('Test', hash2);  // false

JWT

Sign and verify JSON Web Tokens:

import { signJWT, verifyJWT } from '@egomobile/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 '@egomobile/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 ...');
});

Azure AD

You can connect with Azure AD, by using passport and passport-azure-ad modules:

import express from 'express';
import { setupAppForAzureAD } from '@egomobile/microservices';

const app = express();

const { withAzureADBearer } = setupAppForAzureAD(app);

app.get('/', withAzureADBearer(), async (request, response) => {
    // get decoded token
    const authInfo: any = request.authInfo;

    return response.json(authInfo);
});

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

Constants

Name	Description	Example
APPLICATION_INSIGHTS_KEY	Application Insights key.	dd7589fc-1cf9-413e-bf6c-aa1253858b55
AZURE_AD_AUDIENCE	Azure AD audience.	6b3c51b9-7cc0-4327-a901-e5b889efbbaa
AZURE_AD_CLIENT_ID	App ID for Azure AD.	6b3c51b9-7cc0-4327-a901-e5b889efbbaa
AZURE_AD_IDENTITY_METADATA	Identity metadata.	https://myazuread.b2clogin.com/myazuread.onmicrosoft.com/my_policy/v2.0/.well-known/openid-configuration
AZURE_AD_IS_B2C	true if Azure AD is running in B2C context.	true
AZURE_AD_LOGGING_LEVEL	Azure ADlogging level. Possible values are error, info or warn.	info
AZURE_AD_PASS_REQ_TO_CALLBACK	true if Azure AD request should be passed to callback.	false
AZURE_AD_POLICY_NAME	Azure AD policy name.	my_policy
AZURE_STORAGE_CONNECTION_*	The string of the connection to the storage.	DefaultEndpointsProtocol=https;....windows.net
AZURE_STORAGE_CONNECTION_*_CONTAINER	The name of the underlying container.	my_container
AZURE_AD_VALIDATE_ISSUER	true if Azure AD issuer should be validated or not.	false
BCRYPT_ROUNDS	The number of rounds for bcrypt hashing. Default: 10	12
EMAIL_FROM	The email from field.	[e-mail]
EMAIL_HOST	The host for sending mail.	smtp.office365.com
EMAIL_PASSWORD	The email password for authentication.	<some secure password>
EMAIL_PORT	The port for sending mail.	587
EMAIL_SECURE	Should the email be send encryted?	false
EMAIL_USER	The email user for authentication.	[e-mail]
EMAIL_TO	The email to field.	[e-mail]
JWT_SECRET	The secret for signing and validating JWT.	mySecretJWTSecret
LOCAL_DEVELOPMENT	true if app running in local development context or not.	false
LOG_LEVEL	The name of the logging level.	debug
MONGO_DB	The name of the database to connect to.	myDatabase
MONGO_IS_LAZY	If true, MongoDatabase will throw an error, if not enough configuration data is available, the first time an instance of it is used, instead the time an instance of it is created.	true
MONGO_URL	The connection URL.	mongodb://mongo.example.com:27017
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

Diagnostics

The library uses winston as logger:

import { logger } from '@egomobile/microservices';

logger.info('Hello e.GO!', {
    file: __filename
});

Application Insights

Setup Application Insights:

import { setupApplicationInsights } from '@egomobile/microservices';

// you must define 'APPLICATION_INSIGHTS_KEY'
// and must not be in local development context
setupApplicationInsights();

Express

Schema

Use schema namespace, which is a link to embedded joi module, and build-in middlewares to validate input.

import { schema, withDataURI, withSchema } from '@egomobile/microservices';

interface IMySchema {
    email?: string;
    first_name: string;
    last_name: string;
}

const mySchema = schema.object({
    email: schema.string().strict().trim().email().optional()
    first_name: schema.string().strict().trim().min(1).required()
    last_name: schema.string().strict().trim().min(1).required()
}).required();


// withSchema() will automatically add
// middleware, created by express.json()
// with a limit of 128 MB
app.post('/user/register', withSchema(mySchema), async (request, response) => {
    const body: IMySchema = request.body;

    // ...
});

// withDataURI() will automatically add middlewares
// to parse the input
app.put('/user/image', withDataURI(), async (request, response) => {
    // data:<MIME>;base64,<BASE64-DATA>

    const mime = request.headers['content-type'] as string;  // <MIME>
    const body: Buffer = request.body;  // decoded <BASE64-DATA>

    // ...
});

MongoDB

Use MongoDatabase class, which has simple support to handle MongoDB connections:

import { MongoDatabase } from '@egomobile/microservices';

const mongo = new MongoDatabase();
await mongoDb.connect();

// insert
await mongo.insert('myCollection', [{
    uuid: '8d41b8fc-2110-4b05-91ff-0a40c007be9d',
    last_name: 'Kloubert',
    first_name: 'Marcel'
}, {
    uuid: '90b7191d-44ce-43c9-a6e3-b777a8b9c8a6',
    last_name: 'M',
    first_name: 'Tanja'
}]);

// find
const docs = await mongo.find('myCollection', {
    first_name: 'Tanja'
});

// count
const docsCount = await mongo.count('myCollection', {
    first_name: 'Marcel'
});

mongo.disconnect();

NATS

Connect to a NATS server:

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

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

Listener

Listen for events:

import { NatsListener } from '@egomobile/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 '@egomobile/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.