Chapter 10. HTML Service

Apps Script is JavaScript code that executes on Google servers. It is also possible to construct and execute applications that execute in a browser on the PC, but under the control of and communicating with server-based Apps Script.

Why Client Execution?

Apps running on a server cannot have access to the client DOM or to local resources that can make a user experience compelling and immediate. Once client-side script is enabled, it’s possible to create any kind of web application. Generally speaking, JavaScript will run on a local client more efficiently than it does on an Apps Script server and does not need to be limited and controlled as it does when executing in a shared-server environment.

The Downside

Earlier versions of Apps Script came with a UI service with which form controls such as text boxes and other interactive objects could be designed and deployed, in addition to a limited number of event handling capabilities to interact with the user. This capability was fairly basic, but it was also well integrated into Apps Script. The UI service has since been deprecated, and aside from the simplest interactions, the Apps Script frontend experience is now presented using the HTML service, running in a browser on the client.

This means that for any Apps Script application that needs anything more than rudimentary user interaction, the developer must now understand HTML and CSS in addition to JavaScript and the Apps Script services.

The interaction ...

Get Going GAS now with the O’Reilly learning platform.

O’Reilly members experience books, live events, courses curated by job role, and more from O’Reilly and nearly 200 top publishers.