How can I send push notifications to an outlook add-in from a web server?

Question

Problem

I can't seem to find a reference a suggested way to implement sending notifications from a web server to an outlook add-in.

I've looked on:

the officeJS docs, which have a deprecated entry about notifications rest api v2.0, pointing to the Microsoft Graph, which again is deprecated (but without pointing to any up to date version)
stackoverflow, but the questions were either unanswered, or, answering the question with the deprecated notifications api
the officejs Q&A forum, where someone pointed out the Azure Notifications Hub service, but only linked to an android example; but the docs state that it's primarily made to send messages to mobile devices officejs add-ins as a tutorial or reference

Could you help me understand what's the best way to implement push notifications from web server -> outlook add-in?

Context

I personally would like to use Firebase Cloud Messaging, which depends on the Push API under the hood. Is the Push API supported?
WebSockets could also work, but here again I wasn't able to find something before working away on an implementation

user_7823505 · Answer

@nickromano is correct in that an add-in is just a webpage embedded in Outlook, so you may be able to send data to it through websockets or long polling outside of a standard request. However, this is not a supported use case scenario.

user_1603351 · Answer

Web add-ins are not run all the time in Outlook. They are activated in reaction to any event or by users (for example, when a task pane is opened). Moreover, Outlook add-ins are working under the context of the currently selected item(s) only. So, your add-in should be activated if you want to receive any push notifications (by opening a task pane or any event).

Be aware, feature requests on Tech Community are considered, when the dev team go through the planning process. Use the github label: “Type: product feature request” at https://aka.ms/M365dev-suggestions .

How can I send push notifications to an outlook add-in from a web server?

Problem

Context

2 Answers