I am new to Graph APIs and this might be a stupid question to ask but we have a requirement displaying all the channel names in a dropdown in a group and then when user selected a channel based on a button click we need to post some information about our app in the Teams channel user selected. Now to make is seamless we want to try it without making a user sign in so they don't have to sign in every-time.
I checked the Graph APIs but ChannelMessage does not let you SEND a message to a channel without signed in user. Is there a way we can achieve this without asking user to sign in?
Also I see the application level permission have something called "Chat.ReadWriteAll", is it something we can utilize?
Any help is deeply appreciated.