I was looking for an addin/extension for Microsoft Planner to do Gantt charts, and came across this Chrome extension. I realised that Planner must have an API in order to do this, and I had been wanting a project to play around and learn more about APIs so I decided I would build my own wee PHP app to pull a Plan and put it into a Gantt chart (and maybe do some other fun stuff too).
All was going well, I could log in, pull my name etc but when I tried to access Plans, I got error messages. According to the Graph Explorer and the API reference I don't have the appropriate permissions to pull plan details (Group.Read.All, Group.ReadWrite.All).
However, the linked extension above does work for me and I am able to see all my plans so surely there is another way to get the data? Is there some other Planner API I have overlooked? Or some other method of extracting that data other than the Graph API? Any help appreciated, I'm new to playing around with APIs etc...