Overview The databasePlugin.ts file is a TypeScript module that defines a Fastify plugin responsible for connecting to and disconnecting from a MongoDB database using Mongoose. It utilizes the Fastify framework and incorporates hooks to manage the database connection lifecycle during Fastify's initialization and closing.

Dependencies Fastify: The web framework used for building web applications with a focus on speed and low overhead.

Import: FastifyInstance from "fastify" Import: fastifyPlugin from "fastify-plugin" Mongoose: An ODM (Object Data Modeling) library for MongoDB and Node.js.

Import: mongoose from "mongoose" Functions connectToDatabase(): Promise

Establishes a connection to the MongoDB database using the URI provided in the environment variables. Logs a success message upon successful connection. Throws an error if the connection fails. disconnectDatabase(): Promise

Disconnects from the MongoDB database using Mongoose. Logs a message indicating successful disconnection. databasePlugin(fastify: FastifyInstance): Promise

Fastify plugin function responsible for connecting to the MongoDB database and adding a hook to disconnect when Fastify is closing. Calls connectToDatabase() to establish the initial connection. Adds an "onClose" hook to invoke disconnectDatabase() when Fastify is closing.