Develop Google Workspace add-ons to attach files to Calendar events from third-party services

Google Workspace developers can now create Google Workspace add-ons that attach files to a Google Calendar event from any third-party service. This feature enables developers to create add-ons that support attachments from a wide range of sources beyond Google Drive, such as digital whiteboard, content creation, or file management tools. 

Users who have the relevant add-ons installed will be able to attach files from these sources to a Calendar event, and attendees can view the event with the attachment on the web or on mobile.

After attaching files in Calendar on the web, users can view the event with the attachment on the web or on mobile. 

• Developers: You can now develop add-ons that support attaching files from sources other than Google Drive. To get started, learn more about extending Calendar with Google Workspace add-ons and adding attachments with a callback function. 
• Admins: There is no admin control for this feature. Visit the Help Center to learn more about managing Google Workspace Marketplace apps. 
• End users: If allowed by your admin, you’ll be able to install a Calendar add-on using the “+” button in the quick access side panel or via the Google Workspace Marketplace. End users need to install a compatible add-on to enable this feature. 

• This feature is available now for all developers and users. 

• Available to all Google Workspace customers, as well as legacy G Suite Basic and Business customers 

• Google Workspace Developer Documentation: Google Workspace Add-ons 
• Google Workspace Developer Documentation: Extending Calendar with Google Workspace add-ons 
• Google Workspace Developer Documentation: Add attachments with a callback function 
• Google Workspace Admin Help: Manage Google Workspace Marketplace apps 
• Google Help: Get extra Calendar tools