In this guide, we will explore the Novu mono-repo structure and high-level structure of the different libraries and services we use.

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Setting up the monorepo

Novu uses PNPM as its package manager, and NX as its build CLI tool. PNPM reduces the installation time and generates symlinks for all the internal packages we use. To initialize the monorepo, run the following command from the root of the project: 
npm run setup:project
This will:
  • run pnpm install, which will download all the needed dependencies and create symlinks for packages.
  • copy the .env.example file to the .env file for the API service.
  • execute the npm run build command to build all the dependency trees locally.
For additional information on running Novu locally, visit the run locally guide.

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Apps

The apps folder contains high-level applications and APIs. The app’s outputs usually contain deployable units that a user can interact with either as an API or as a web/cli application.
1

API

The API package is our main service for handling backend logic. It handles anything from authentication, authorization, workflow management, triggering events, etc… This is where the Novu business logic is handled.
2

WS aka Web Socket

This is the WebSocket NestJs server which connects to the widget and provides real-time updates about new notifications to the widget consumer.
3

Web aka Admin Panel

This is the Novu admin panel which is used to visually communicate with the API. You can configure workflows, manage content, enable or disable notifications, visually track the notification activity feed, etc…The WEB project is a create-react-app built, well, with React. 😄
4

Widget

This is the client of our embeddable Inbox widget. It is consumed mainly with the embed script in an Iframe. We can access it on port 4500 to interact with it directly.
5

Worker

This is our service for managing and handling workers.

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Libs

1

@novu/dal

The DAL is our Data-Access-Layer. This is our connection to the DB service and wraps MongoDB and mongoose. When another service or API needs to consume the DB, it does not do that directly but uses the DAL as an interface. Importing mongoose directly outside the dal is not allowed.
2

@novu/testing

This is a utility library that contains testing helpers. The testing helpers can generate test sessions and other functionality for e2e and unit-tests between our services.
3

@novu/shared

The shared library contains reusable code and typescript interfaces between client and server packages. Code in the shared library should not contain any sensitive content because it can be accessed and downloaded by the web or other clients.
4

@novu/embed

This is the connector between our client’s web app and the widget project. It’s a small shim script that generates an iframe and attaches it to a client-specified div to host the notification widget.If you are familiar with the Google Analytics embedded snippet or intercom-like embeddings, it uses the same mechanics.

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Packages (on npm)

1

@novu/node

A Standalone Node.js wrapper around the Novu API. Exists to provide type-safe and easier access to the different API endpoints Novu exposes (Triggers, subscribers, etc…).
2

@novu/nest

A Nest.js wrapper around the @novu/node package was created by the community to easily interact with the core library from a nest project. Also released on NPM as a package.
3

@novu/react

This is the library that powers the Novu Inbox. It is a React component that can be embedded in any React application.

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Providers

These are the API wrappers created by the community to wrap communication providers in the following channels: Novu provides a single API to manage providers across multiple channels with a simple-to-use interface.

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💌 Email

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📞 SMS

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📱 Push

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👇 Chat

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📱 In-App