To subscribe to events using Apps Script, you can now use the Advanced Google Workspace Events service.
In the May 02, 2024 Google Apps Script release notes it was announced that a new Advanced Google Workspace Events service is available to let developers use the Google Workspace Events API directly in Google Apps Script. The Google Workspace Events API is a relatively new API, which was released to developer preview in January, 2024. The Google Workspace Events API uses a subscription model to handle resource changes. When you create a subscription, you specify the target resource (such as a Google Chat space or Google Meet meeting space) and the event types that you want to subscribe to. The API then sends notifications to your specified endpoint whenever an event occurs for that resource and event type.
In the case of the new Advanced Google Workspace Events service the linked documentation includes samples for using the new service with Google Chat. It’s worth noting that the Advanced Google Workspace Events service is designed specifically on managing subscriptions to events. While it lets you to control the flow of information and manage event subscriptions in your Apps Script projects, the actual processing and handling of event data occurs separately.
The linked documentation page provides sample code as well as outlines all the prerequisites.
