method

stream_from

v8.0.0 - Show latest stable - 0 notes - Class: Streams

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stream_from(broadcasting, callback = nil, coder: nil, &block) public

Start streaming from the named `broadcasting` pubsub queue. Optionally, you can pass a `callback` that’ll be used instead of the default of just transmitting the updates straight to the subscriber. Pass `coder: ActiveSupport::JSON` to decode messages as JSON before passing to the callback. Defaults to `coder: nil` which does no decoding, passes raw messages.

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# File actioncable/lib/action_cable/channel/streams.rb, line 90
      def stream_from(broadcasting, callback = nil, coder: nil, &block)
        broadcasting = String(broadcasting)

        # Don't send the confirmation until pubsub#subscribe is successful
        defer_subscription_confirmation!

        # Build a stream handler by wrapping the user-provided callback with a decoder
        # or defaulting to a JSON-decoding retransmitter.
        handler = worker_pool_stream_handler(broadcasting, callback || block, coder: coder)
        streams[broadcasting] = handler

        connection.server.event_loop.post do
          pubsub.subscribe(broadcasting, handler, lambda do
            ensure_confirmation_sent
            logger.info "#{self.class.name} is streaming from #{broadcasting}"
          end)
        end
      end

stream_from

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