ruby - React with Rails REST api - actioncable -


i have react frontend(not using react-rails gem) , want use rails api realtime interaction. have post.coffee code in rails working actioncable:

app.post = app.cable.subscriptions.create "postchannel", connected: ->  disconnected: ->  received: (data) -> console.log(data) document.getelementbyid('test').innerhtml = data['message']  notify: (message) -> @perform 'notify', message: message

and post_channel.rb

class postchannel < applicationcable::channel   def subscribed     stream_from "post_channel"   end    def unsubscribed     # cleanup needed when channel unsubscribed   end    def notify(data)     actioncable.server.broadcast 'post_channel', message: data['message']   end end

working example:

working example

now in react app, lets on page load [ componentwillmount() ], want 'call' notify method post_channel.rb. how it? have searched method , saw post's accepted answer: how use actioncable api

so in react app's componentwillmount() lifecycle, have code:

  componentwillmount() {      var cable = actioncable.createconsumer('ws://localhost:8000/cable');      cable.server.broadcast 'post_channel', { message: 'ji'}   }

i got ws url development.rb: enter image description here

the code in componentwillmount not call websocket in rails app. how this? dont see resource. or recommend websocket library best react-rails stack?

solution

should similar rails .coffee code

componentwillmount() {   var cable = actioncable.createconsumer('ws://localhost:8000/cable');    var subscription = cable.subscriptions.create('postchannel',     {       connected: function() {         // calls `notify` method in `post_channel` once subscription has connected         this.notify({ message: 'ji'});          // seems me `notify` code above once-off action , won't using subscription anymore;         // if that's case then, uncomment line below unsubscribe after performing `notify` above         // this.unsubscribe();       },       received: function(data) {         // there new message; here...         console.log(data.message);       },       notify: function(message) {         this.perform('notify', message: message)       }     }   ) }

recommendation

  • you'd ought have 1 consumer object (use actioncable.createconsumer('ws://localhost:8000/cable'); once), , make global in app speed things (and less code), because you'll have 1 websocket endpoint anyway (the rails server), unless of course have different multiple websocket urls (on different rails servers or apps?). might want make subscription variable above global, can .notify(...) anywhere want, , not instantiating subscription each time.

  • i built gem live_record syncs records js-client. though not intentionally support pushing "messages" rails server, in case might find useful, feel free try out! :)


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