title: Google PubSub - add message on scheduling
body: <h2>Background</h2>
  
  <p>I have a Google cloud Pub-Sub queue that listen by Google Function python script. My function script is waiting for incoming messages on queue and execute them. </p>
  
  <p>On of my tasks is to scale up\down my environment. This logic should happen every day on 00:00 (scale up) and on 12:00 (scale down). </p>
  
  <p>I want to automate the message insertion for the queue on specific time. </p>
  
  <p>Requirements: </p>
  
  <ul>
  <li>Make it easy configurable (if the scaling time is changing for
  example).</li>
  <li>Without need on virtual machine that cost me money all the day.</li>
  </ul>
  
  <h2>Possible solution were rejected</h2>
  
  <ol>
  <li>Use Linux VM with crontab to run a local script. The script will en-queue a message for the gcp PubSub. Con: Need the machine working all day long for just few seconds. </li>
  <li>Use Kubernetes cronjob and run the script on specific time. Cons: too much configuration. Not easy to edit config. No needs to gcp Function - it can be the job itself.</li>
  </ol>
  
  <h2>The Question</h2>
  
  <p>What is the simplest way to do it? </p>