Implement backend discovery via SSDP

[dekarl]

It would be very nice to automagically configure the backend connection in local network environments iff the backend URL contains the default value and only one backend is found via SSDP.
E.g. search for deviceType urn:schemas-mythtv-org:device:MasterMediaServer:1, then use the URL base for the backend connection (see http://www.upnp-database.info/device.jsp?deviceId=812 for an example)

Android Network Discovery Documentation
https://developer.android.com/training/connect-devices-wirelessly/nsd.html

[dekarl]

#231 Re-discovering the backend in case of connection problems (e.g. reinstalled with a different IP) would be nice, too.

[dmfrey]

I envision discovery happening every time the application loads and either updates the shared preferences or leaves it as is if it is unchanged, then you proceed to the main interface. The big question would be those users who have multiple master backends on the network. I know in most cases, there will be just 1. But there are uses like @billmeek who runs a main system based on the latest release and also a system based on the git head. He can clarify his setup further.

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On Mon, Jan 23, 2017 at 3:11 PM Karl Dietz ***@***.***> wrote: #231 <#231> Re-discovering the backend in case of connection problems (e.g. reinstalled with a different IP) would be nice, too. — You are receiving this because you were assigned. Reply to this email directly, view it on GitHub <#178 (comment)>, or mute the thread <https://github.com/notifications/unsubscribe-auth/AA5yzP8oZ6aBxMBvAdtaQsoRmsoGaynqks5rVQlngaJpZM4IxNt1> .

[billmeek]

I've even had an old box running 25, 26, 27 and 28 (doesn't
record much, and not of use now with the recordedid only
available in 0.28+).

Recall that there were one, or a few, users that didn't want
SSDP running on their backends. Not clear why, but they
didn't. This was back in the days of Android Frontend.

@dekarl take a peek at #231. Not the automatic solution,
but one for a more casual user that needs help diagnosing
connection failures.

[dmfrey]

@dekarl its a start ^^^