We have a desktop app with which we want to integrate Office 365 calendar. We will have our users provide their consent by authorising the app in office 365. I wonder if I can use any specific permission and/or api that would help us know if our office 365 office.js addin is installed by that user. This works great with VSTO addin as we can get the info from system registry, however, as Office 365 addin is installed on cloud no such registry can be found and we won’t be able to know.
2 Answers
Exchange will create a subfolder for each installed web addin in a special folder named WebExtAddins. The folder is on the same level as the other special folders (e.g. the Inbox), but is hidden. You can see that folder (and its subfolders) in OutlookSpy - select the top folder of the store (parent of Inbox etc.), click IMAPIFolder button on the OutlookSpy ribbon, go to the GetHierarchyTable, double click on the folder named WebExtAddins.
It seems that there is no good way to check directly now. Just like you said,Office 365 add-in is installed on Cloud. Since it runs through a separate browser process (Like IE). After plug-ins are loaded, we typically see two IE processes in the process manager. Here's a detail. If your Office is 32-bit, then its core process will be a 32-bit one. You can see that if you load multiple plug-ins, the memory it uses will gradually increase. However, it is still a process.
Also, if your Windows is 64-bit, it will create another 64-bit IE process which is actually a call relationship. As you can see from the diagram below, the 32-bit process is actually calling the 64-bit process.