nilscam
Hello 
,
I would like to monitore phoenix socket process, to count the current user connected to my application, without having them to join a channel.
defmodule ChatWeb.UserSocket do
use Phoenix.Socket
channel "topic:*", ChatWeb.Channel
def connect(_params, socket) do
:ok = SocketWatcher.monitor(socket.transport_pid)
{:ok, socket}
end
def id(_socket), do: nil
end
The problem here is that transport_pid is nil…
As explained chrismccord in this post, a socket transport_id field is nil until the connection has been authorized in UserSocket.connect/3.
Is there a way to implement a callback for UserSocket.connect/3 method, where i can get this transport_id and monitore it.
Thanks for your help.
Where Next?
Trending in Questions
Other Trending Topics
Latest Phoenix Threads
Latest on Elixir Forum
Sponsor Spotlight
Practical resources that improve the lives of professional developers.
Categories:
Sub Categories:
Forums
Popular Tags
- #ecto
- #liveview
- #troubleshooting
- #learning-elixir
- #library
- #deployment
- #erlang
- #testing
- #genserver
- #mix
- #absinthe
- #remote-other
- #otp
- #plug
- #how-to-question
- #macros
- #postgres
- #elixirconf
- #channels
- #exunit
- #discussion
- #code-sync
- #podcasts
- #javascript
- #onsite
- #dialyzer
- #docker
- #authentication
- #umbrella
- #full-time-contract
- #podcasts-by-brainlid
- #ai
- #ecto-query
- #elixirconf-us
- #blog-post
- #elixir-ls
- #phoenix_html
- #iex
- #graphql
- #genstage
- #websockets
- #supervisor
- #advent-of-code
- #distillery
- #processes
- #elixirconf-eu
- #api
- #forms
- #metaprogramming
- #hex
Our Sponsors
Build Elixir applications with speed and confidence.
Supporting innovation across the BEAM ecosystem.
We build reliable cloud platforms for business-critical systems.
Catch errors, track performance, monitor hosts and more.
Elixir, Erlang & BEAM conferences from Code Sync - join us in 2026!
Practical resources that improve the lives of professional developers.
Master modern tools, write cleaner code, and tackle real-world challenges.
Bringing learning, work and compliance together since 1987.
The team behind Membrane, Popcorn, LiveDebugger. Available for hire.
Courses that'll move you from confusion to "Aha, now I get it!"
Showing Posts 1 to 9- Show Best Posts
- Show All (oldest first)
- Show All (newest first)
LostKobrakai
Can you elaborate on that constraint? Phoenix Presence basically solved the problem of tracking users.
nilscam
In this monitore function, i use Presence ^^
I would like to do something like this. But this code doesn’t work anymore with newer phoenix versions. Transport_id is now nil until the connection has been authorized.
LostKobrakai
You should be able to do exactly that in a channel.
nilscam
But as i said in the first sentence of my Post: “I would like to monitore phoenix socket process, to count the current user connected to my application, without having them to join a channel.”
LostKobrakai
Which is why I asked what’s preventing you from using a channel. Is there a particular reason for this constraint? Letting users join an additional channel doesn’t sound like a particular high barrier.
nilscam
I’m building a SAAS product. I bill for number of simultaneous connected users.
Actually, in the SDK I give to my clients, when they connect to my service, i force them to join a special channel which is only used to count the number of simultaneous users thanks to
Phoenix.Presence.The problem is that if my clients comment the line that join this special channel, they can potentially use my service for free without any limit.
LostKobrakai
Then it might be worth going the route @chrismccord mentioned in the already linked topic and implement a custom
Phoenix.Socket, which allows you to track the socket process using presence.nilscam
implementing my own socket seems pretty complicated compared to what I need.
I just need a callback that give me the pid of newly connected socket.
I think there must be an alternative solution that can solve my problem more simply.
LostKobrakai
Copy the implementation of phoenix and add the necessary callback or try to make a case for adding it to phoenix. The latter could include the first one as a PR.