Phoenix Tracker vs. Presence

Let's look at the difference between Tracker and Presence.

We'll cover the following

Presence
Which one is better?

Presence

Phoenix Presence is an implementation of Tracker that provides helper functions for working with Channels. Its implementation of handle_diff/2 broadcasts changes locally using PubSub when a process joins or leaves the Tracker. Clients listen for change messages and process them to keep a client-side version of the Tracker state. The official Phoenix JavaScript library includes a Presence class that handles the messages automatically for us. The following figure shows the flow of Presence updates:

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Getting Started with Phoenix

Powering Real-time Applications with Phoenix

First Steps with Phoenix Channels

Restrict Socket and Channel Access

Dive Deep into Phoenix Channels

Avoid Performance Pitfalls

Build a Real-time Sneaker Store

Break Your Application with Acceptance Tests

Build a Real-time Shopping Cart

Track Connected Carts with Presence

Deploy Our Application to Production

Manage Real-time Resources

Hands-on with Phoenix LiveView

Single-page Applications with React

Wrap Up!

Appendix

Phoenix Tracker vs. Presence

Presence