Notify socket.io users when MongoDB data collection changes

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Notify socket.io users when MongoDB data collection changes

✓ Published0🌍 Public

Last edited Feb 7, 2018

Created on Nov 11, 2019

This example shows how MongoDB data changes are streamed to connected Socket.io users in real time. It uses the MongoDB `User.watch()` change stream to monitor collection modifications, and on each change, queries all users via `User.find({})` before emitting the updated dataset through `socket.emit('users', data)`. The code integrates with an Express app and a Socket.io server, logging connection events and collection changes to the console. No visualization library is involved; the focus is on the backend data pipeline that pushes fresh data to clients.

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