title: Deployment of Cloud Function that handle write and updates events
body: <p>I want to create a cloud function on python that helps me to count the number of documents in a collection everytime an object of a collection is been created or deleted and I found an example of <a href="https://cloud.google.com/functions/docs/calling/cloud-firestore" rel="nofollow noreferrer">Cloud Firestore Triggers</a> but I have a problem with this part of the code databases/(default) what do I should write on default? I have tried project_id+".firebaseio.com" or just".firebaseio" but my function isn't called.  Thank you for your time.</p>
  
  <pre><code>gcloud functions deploy FUNCTION_NAME \
    --runtime RUNTIME \
    --trigger-event providers/cloud.firestore/eventTypes/document.write \
    --trigger-resource projects/YOUR_PROJECT_ID/databases/(default)/documents/messages/{pushId}
  </code></pre>