Microservice for handling notifications to users through real time notifications, email, or SMS. This microservice uses the loopback4-notifications module to publish/send the notifications.
npm i @sourceloop/notification-service
-
Install the notification service
npm i @sourceloop/notification-service
-
Install the loopback4-notifications module -
npm i loopback4-notifications
-
Set the environment variables.
-
Run the migrations.
-
Add the
NotificationServiceComponent
to your Loopback4 Application (inapplication.ts
).// add Component for AuthenticationService this.component(NotificationServiceComponent);
-
Set up a Loopback4 Datasource with
dataSourceName
property set toNotifDbSourceName
. You can see an example datasource here. -
Using this service you can send Email, SMS and push notifications. Steps to add any of these are described below. You may choose to add one or more of these depending on your requirement.
-
Email Notifications with Amazon SES -
-
Bind the SES Config to the
SESBindings.Config
key -this.bind(SESBindings.Config).to({ accessKeyId: process.env.SES_ACCESS_KEY_ID, secretAccessKey: process.env.SES_SECRET_ACCESS_KEY, region: process.env.SES_REGION, });
-
Implement an SES Provider(refer this) or you can import the default SES provider from the loopback4-notifications module and bind it to the
NotificationBindings.EmailProvider
key as described here.
-
-
Email Notifications with Nodemailer -
- Bind the Nodemailer Config to the
NodemailerBindings.Config
key -
this.bind(NodemailerBindings.Config).to({ pool: true, maxConnections: 100, url: '', host: 'smtp.example.com', port: 80, secure: false, auth: { user: 'username', pass: 'password', }, tls: { rejectUnauthorized: true, }, });
- Implement a Nodemailer Provider(refer this) or import the default Nodemailer provider from the loopback4-notifications module and bind it to the
NotificationBindings.EmailProvider
key as described here,
- Bind the Nodemailer Config to the
-
SMS Notification with Amazon SNS -
- Bind the SNS Config to the
SNSBindings.Config
key -
this.bind(SNSBindings.Config).to({ accessKeyId: process.env.SNS_ACCESS_KEY_ID, secretAccessKey: process.env.SNS_SECRET_ACCESS_KEY, region: process.env.SNS_REGION, });
- Implement an SnsProvider(refer this) or import the default SNS provider from the loopback4-notifications module and bind it to the
NotificationBindings.SMSProvider
key -
import {NotificationBindings} from 'loopback4-notifications'; import {SnsProvider} from 'loopback4-notifications/sns'; // or your own provider ... this.bind(NotificationBindings.SMSProvider).toProvider(SnsProvider); ...
- Bind the SNS Config to the
-
Push Notifications with Pubnub -
- Bind the Pubnub Config to the
PubnubBindings.Config
key -
this.bind(PubnubBindings.Config).to({ subscribeKey: process.env.PUBNUB_SUBSCRIBE_KEY, publishKey: process.env.PUBNUB_PUBLISH_KEY, secretKey: process.env.PUBNUB_SECRET_KEY, ssl: true, logVerbosity: true, uuid: 'my-app', cipherKey: process.env.PUBNUB_CIPHER_KEY, apns2Env: 'production', apns2BundleId: 'com.app.myapp', });
- Implement a Pubnub Provider(refer this) or import the default Pubnub provider from the loopback4-notifications module and bind it to the
NotificationBindings.PushProvider
key -
import {NotificationBindings} from 'loopback4-notifications'; import {PubNubProvider} from 'loopback4-notifications/pubnub'; //or your own provider ... this.bind(NotificationBindings.PushProvider).toProvider(PubNubProvider); ...
- Bind the Pubnub Config to the
-
Push Notifications with Socket.io -
- Bind the Socket.io Config to the
SocketBindings.Config
key -
this.bind(SocketBindings.Config).to({ url: process.env.SOCKETIO_SERVER_URL, });
- Implement a SocketIO Provider(refer this) or import the default Socket.io provider from the loopback4-notifications module and bind it to the
NotificationBindings.PushProvider
key -
import {NotificationBindings} from 'loopback4-notifications'; import {SocketIOProvider} from 'loopback4-notifications/socketio'; //or your own provider ... this.bind(NotificationBindings.PushProvider).toProvider(SocketIOProvider); ...
- Bind the Socket.io Config to the
-
-
Start the application
npm start
interface SESMessage {
receiver: {
to: {
id: string; //Email address
name?: string;
}[];
};
subject: string;
body: string;
sentDate: Date;
type: 1; //Email
options?: {
fromEmail: string; // We do not support attachments with SES Provider yet.
};
}
interface NodemailerMessage {
receiver: {
to: {
id: string; //Email address
name?: string;
}[];
};
subject: string;
body: string;
sentDate: Date;
type: 1; //Email
options?: {
from: string;
subject?: string;
text?: string;
html?: string;
attachments?: {
filename?: string | false;
cid?: string;
encoding?: string;
contentType?: string;
contentTransferEncoding?: '7bit' | 'base64' | 'quoted-printable' | false;
contentDisposition?: 'attachment' | 'inline';
headers?: Headers;
raw?:
| string
| Buffer
| Readable
| {
content?: string | Buffer | Readable;
path?: string | Url;
};
}[];
};
}
interface SMSMessage {
receiver: {
to: {
id: string; // TopicArn or PhoneNumber
name?: string;
}[];
};
subject: undefined;
body: string;
sentDate: Date;
type: 2; //SMS
options?: {
messageType: any;
};
}
interface PubNubMessage {
receiver: {
to: {
type: 0; //Channel Type
id: string; //Channel identifier
name?: string;
}[];
};
subject: string;
body: string;
sentDate: Date;
type: 0; //Push Notification
options?: {
sound: string;
};
}
interface SocketMessage {
receiver: {
to: {
type: 0; //Channel Type
id: string; //Channel identifier
name?: string;
}[];
};
subject: string;
body: string;
sentDate: Date;
type: 0; //Push Notification
options?: {
path?: string;
};
}
Name | Required | Default Value | Description |
---|---|---|---|
NODE_ENV |
Y | Node environment value, i.e. dev , test , prod |
|
LOG_LEVEL |
Y | Log level value, i.e. error , warn , info , verbose , debug |
|
DB_HOST |
Y | Hostname for the database server. | |
DB_PORT |
Y | Port for the database server. | |
DB_USER |
Y | User for the database. | |
DB_PASSWORD |
Y | Password for the database user. | |
DB_DATABASE |
Y | Database to connect to on the database server. | |
DB_SCHEMA |
Y | Database schema used for the data source. In PostgreSQL, this will be public unless a schema is made explicitly for the service. |
|
JWT_SECRET |
Y | Symmetric signing key of the JWT token. | |
JWT_ISSUER |
Y | Issuer of the JWT token. |
Here is a sample Implementation DataSource
implementation using environment variables and PostgreSQL as the data source.
import {inject, lifeCycleObserver, LifeCycleObserver} from '@loopback/core';
import {juggler} from '@loopback/repository';
import {NotifDbSourceName} from '@sourceloop/notification-service';
const config = {
name: NotifDbSourceName,
connector: 'postgresql',
url: '',
host: process.env.DB_HOST,
port: process.env.DB_PORT,
user: process.env.DB_USER,
password: process.env.DB_PASSWORD,
database: process.env.DB_DATABASE,
schema: process.env.DB_SCHEMA,
};
@lifeCycleObserver('datasource')
export class NotificationDbDataSource
extends juggler.DataSource
implements LifeCycleObserver
{
static dataSourceName = NotifDbSourceName;
static readonly defaultConfig = config;
constructor(
// You need to set datasource configuration name as 'datasources.config.Notification' otherwise you might get Errors
@inject('datasources.config.Notification', {optional: true})
dsConfig: object = config,
) {
super(dsConfig);
}
}
Here is a sample implementation of how we can blacklist a user(s).
Create a new provider:
import {BindingScope, injectable, Provider} from '@loopback/core';
import {
INotificationFilterFunc,
Notification,
} from '@sourceloop/notification-service';
@injectable({scope: BindingScope.TRANSIENT})
export class NotificationfilterProvider
implements Provider<INotificationFilterFunc>
{
constructor() {}
value() {
return async (notif: Notification) => this.notificationFilterFunc(notif);
}
blacklistedUsers = ['id1', 'id2']; //ID's of blacklisted users
notificationFilterFunc(notif: Notification) {
const receivers = notif!.receiver.to;
const result = receivers.filter(receiver => {
return this.blacklistedUsers.indexOf(receiver.id) === -1;
});
notif.receiver.to = result;
return notif;
}
}
Add the following line to src/application.ts
file
this.bind(NotifServiceBindings.NotificationFilter).toProvider(
NotificationfilterProvider,
);
Note: One can modify the provider according to the requirements
The migrations required for this service are processed during the installation automatically if you set the NOTIF_MIGRATION
or SOURCELOOP_MIGRATION
env variable. The migrations use db-migrate
with db-migrate-pg
driver for migrations, so you will have to install these packages to use auto-migration. Please note that if you are using some pre-existing migrations or databases, they may be affected. In such a scenario, it is advised that you copy the migration files in your project root, using the NOTIF_MIGRATION_COPY
or SOURCELOOP_MIGRATION_COPY
env variables. You can customize or cherry-pick the migrations in the copied files according to your specific requirements and then apply them to the DB.
Authorization: Bearer where is a JWT token signed using JWT issuer and secret.
Content-Type: application/json
in the response and in request if the API method is NOT GET
{version}: Defines the API Version
Status | Description |
---|---|
200 | Successful Response. Response body varies w.r.t API |
401 | Unauthorized: The JWT token is missing or invalid |
403 | Forbidden : Not allowed to execute the concerned API |
404 | Entity Not Found |
400 | Bad Request (Error message varies w.r.t API) |
201 | No content: Empty Response |
Visit the OpenAPI spec docs