Action Cable image publisher

index.html.erb

<div class="min-w-full flex flex-row">
  <%= turbo_stream_from "demo" %>
  <div id="demo"></div>
</div>

publisher

#!/usr/bin/env ruby

# Run this script as:
#
# bundle exec bin/publisher path/to/some.png

require_relative "../config/application"
Rails.application.initialize!

TEMPLATE = <<~HTML
 <turbo-stream target="demo" action="replace">
   <template>
     <div id="demo">
       <h2>Frame: %{number}</h2>
       <img src="data:image/png;base64, %{data}" />
     </div>
   </template>
 </turbo-stream>
HTML

image = ARGF.read
data = Base64.strict_encode64(image)
stream_name = Turbo::StreamsChannel.send(:stream_name_from, "demo")

100.times do |number|
  content = TEMPLATE % {number:, data:}
  ActionCable.server.broadcast stream_name, content
end