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Discussion on: First Ever DEV Contest: Build a Realtime App with Pusher

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kayis profile image
K

The use-cases of Channels are also a bit more narrow.

It seems to me that the main idea behind channels is, that you publish changes from the server to the client.

For example, I change a blog-post and people on dev.to get notified that there was an update to that post.

While socket.io lets you publish events from the clients, that go over your server logic to other clients.

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zmarkan profile image
Zan Markan • Edited

While that's true for Public channels (the simplest use-case) - the Channels API supports client events too - using either Private or Presence channels.

pusher.com/docs/client_api_guide/c...

The tl;dr; version is:

  • You need to have some authorization logic implemented - so you know which user is which, and then you can trigger events from users.
  • You also need to enable them in the dashboard - it's under the App Settings tab
  • That's where the rate limiting (10 messages per user per second) comes into effect - as clients could generate a LOT of events very quickly
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kayis profile image
K

But can I control the client events on my server somehow?

For example, if I want to create a game, I need pipe the client events through some server side logic.

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zmarkan profile image
Zan Markan • Edited

You could do that using WebHooks, they allow you to capture all client events on the server - pusher.com/docs/webhooks#client_ev...

Alternatively you could create an API through which the clients would communicate, and the server would broadcast the events.
It really depends on your particular use-case, what kind of events will your clients be creating, and what makes the most sense for it.

Webhooks wouldn't for instance allow you to block client events, only observe them.

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knyzorg profile image
Slava Knyazev

How easy would it be to move from socket.io to pusher and vice-versa?

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zmarkan profile image
Zan Markan • Edited

As the core concepts of subscriptions, channels, and events are quite similar, it should be a fairly quick migration - but of course it all depends on your concrete project and implementation.

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kayis profile image
K • Edited

Is there a way to close user connections on the server?

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zmarkan profile image
Zan Markan

I'll double check but I don't think so.

You could send a message to a particular user that you wish to disconnect and handle that clientside.

What is your use-case for this?

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kayis profile image
K

I want to use presence channels for games. When a game is finished, the users should be removed from the channel.

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zmarkan profile image
Zan Markan

Ah yeah - just send a message that tells the clients to unsub from the channel, that should be the best way.

I've asked the team working on Channels and we don't support terminating connections from the server.

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kayis profile image
K

Well, guess for this contest it should be enough, thank you.