Jairo
As far as I know AppEngine will still not run Streamlit for any length of time. That was certainly my experience and I abandoned that approach some months back.   The issue is Websocket support and timeout.
GKE deployment is mostly straightforward, it gets more complicated if you want to use the Identity Aware proxy to secure access to your pages.    We did increase the Websocket timeouts for our GKE configurations.
These two blog posts are helpful

  
      
      Rui Costa – 27 Apr 20
  
  
    

Run Streamlit.io on Google Cloud Kubernetes - Rui Costa 139

In this tutorial, I will create a container for the Streamlit application, deploy it to Google Cloud Registry, build a Kubernetes cluster, deploy the application to the newly created cluster, create a GLSB, and secure it with SSL.


  
  
    
    
  
  



  
      
      Rui Costa – 29 Apr 20
  
  
    

Secure Streamlit.io running on Google Cloud Kubernetes - Rui Costa 67

In this post, I will walk you through on how to secure the application running on Kubernetes with Google Cloud Identity-Aware Proxy (IAP).