// Module included in the following assemblies:
//
// * cloud_experts_tutorials/cloud-experts-deploying-application/cloud-experts-deploying-application-lab-overview.adoc

:_mod-docs-content-type: REFERENCE
[id="cloud-experts-deploying-application-lab-overview-ostoy-app_{context}"]
= About the OSToy application

[role="_abstract"]
OSToy is a simple Node.js application that you will deploy to a ROSA cluster to help explore the functionality of Kubernetes. This application has a user interface where you can:

* Write messages to the log (stdout / stderr).
* Intentionally crash the application to view self-healing.
* Toggle a liveness probe and monitor OpenShift behavior.
* Read config maps, secrets, and env variables.
* If connected to shared storage, read and write files.
* Check network connectivity, intra-cluster DNS, and intra-communication with the included microservice.
* Increase the load to view automatic scaling of the pods to handle the load using the Horizontal Pod Autoscaler.
* Optional: Connect to an AWS S3 bucket to read and write objects.

== OSToy Application Diagram

image::ostoy-arch.png[OSToy architecture diagram]