How To broadcast from a background job?

1

I have a session where a user is clicking buttons on the front-end. A click is accepted by the controller, and spawn a Sidekiq background job. At this point the controller updates the screen using a Turbo response. I would like to also update the screen inside the background job. Is there a way to connect the background job to the turbo stream set for this user session?

1 Like
2

Wow. Who knew such a simple question had no answer. I can only assume it either no one uses Turbo and background jobs, or it truly is stunningly easy to broadcast a message from a job to a specific browser session.

Or quite frankly, this is impossible, and I should forget it and move on. Can any who has dabbled with this please comment and help a guy out a little bit?

3

You can broadcast a TurboStream (from the affected model) and if you’ve registered a turbo-stream on the page, it will do whatever you configured that broadcast to do (prepend, append to a collection; replace; remove) in any page that is still connected to the server and listening for cable traffic. Turbo-Frames respond to a browser request, not a background server request. Once you queue a job in the background, the request is over, and there can be no further reply.

Walter

4

Ok thanks. So unless the background job affects a model, there is no hope of updating from a job. Good to know.

5

Not correct. Models have convenience methods to make it easier, but you can broadcast without a model using Turbo::StreamsChannel.

Alert ALL users

<%= turbo_stream_from :alerts %>

Turbo::StreamsChannel.broadcast_render_to(:alerts, target: 'alerts', partial: 'alerts/my_partial', locals: { message: alert.message })

However, models do help limit the scope as to who receives the broadcast. For example, only broadcast alerts to a specific user

Alert Specific users

<%= turbo_stream_from current_user.id, :alerts %>

# alert specific user
Turbo::StreamsChannel.broadcast_render_to(@alert.user_id, :alerts, target: 'alerts', partial: 'alerts/my_partial', locals: { message: @alert.message })
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6

Ahhh, so maybe this will work? All my templates have a current_shop. The background job works on a current shop in the sense that it will do work on behalf of the shop. So if in my template where a button was clicked to inform the server “hey server, start a job”, if I have a turbo element as in

<%= turbo_stream_from current_shop, :alerts %>

and when my background job ends, I then run a

Turbo::StreamChannel.broadcast_render_to(current_shop, :alerts, target: 'alerts', partial: 'alerts/my_partial', locals: {message: 'Job completed'}

That would present an alert on the screen with that message? I am going to have to try that out. If that works, that is pretty cool.

7

Any update on your work here? Trying same solution, but the SteamChannel broadcast doesn’t seem to have any affect from within the background job.

8

I never tried what I said I would try! Ack! Oopsie. I cannot help with an answer right now.

9

In your browser developer tools, can you see the message broadcast over the websocket?

10

I have an issue almost similar to this I have a job in which I’m calling a service and in this service I’m using turbo stream channel to broadcast my question in real time. but I’m getting this error : @view_context.formats |= [:html]

this is how I’m writing code:

Turbo::StreamsChannel.broadcast_render_to(
          "draft_question",
          turbo_stream.update(
            target: dom_id(draft_question),
            partial: "admin/import_questions/draft_questions",
            locals: { question: draft_question, current_organization: draft_question.organization_id }
          )
        )

also in my service I’m including the following too:

 include Turbo::StreamsHelper
  include ActionView::RecordIdentifier

can anyone please suggest some solution to resolve this issue: @view_context.formats |= [:html]

11

can anyone guide me about it?

12

So my problem got resolved. I made a delay in job call which helped broadcast stream in getting the dom id.

Before I was calling like this:
ImportQuestionsJob.perform_later(file_id.to_i, current_organization.id)

now I’m calling like this and it is working for me in displaying questions in real time using turbo stream and job:
ImportQuestionsJob.set(wait: 2.second).perform_later(file_id.to_i, current_organization.id)

13

What is the reason for waiting 2 seconds?

It seems a bit hacky. I would not want to delay jobs like that unless there is a very good reason for it?