Understanding the Guestbook application

In this chapter, you will create a Helm chart to deploy the Guestbook tutorial application provided by the Kubernetes community. This application is introduced in the Kubernetes documentation at the following page: https://kubernetes.io/docs/tutorials/stateless-application/guestbook/

The Guestbook application is a simple PHP: Hypertext Preprocessor (PHP) frontend designed to persist messages to a Redis backend. The frontend consists of a dialog box and a Submit button, as illustrated in the following screenshot:

Figure 5.1: The Guestbook PHP frontend

To interact with this application, users can follow these next steps:

1. Type a message in the Messages dialog box.
2. Click the Submit button.
3. When the Submit button is clicked, the message will be saved to a Redis database.

Redis is an in-memory, key-value data store that, in this chapter, will be clustered for data replication. The cluster will consist...