Check if Habitat Payload doc exists before creating one.

[projecthorus]

Check if Habitat Payload doc exists before creating one.

[darksidelemm]

It looks like habitat only supports exporting the entire list of payload documents:
https://habitat.readthedocs.io/en/latest/habitat/habitat/habitat/habitat.views.payload_configuration.html#habitat.views.payload_configuration.name_time_created_map
i.e. no filtering is possible, until you have the entire list. Not so useful if we are running on a slow internet connection.

An alternate approach would be to query spacenear.us for any recent positions for the current payload, using the URL:
http://spacenear.us/tracker/datanew.php?mode=1hour&type=positions&format=json&max_positions=10&position_id=0&vehicle=RS_
If any positions are returned, that indicates a valid payload document is present, and that one doesn't need to be created. A bit of a roundabout solution, but it would work.

[darksidelemm]

Interim fix for this in #62

[ED6E0F17]

I have already hit my quota of stupid mistakes for this week, so I am a bit nervous about mentioning this, but the fix seems to be disabled:

https://github.com/projecthorus/radiosonde_auto_rx/blob/master/auto_rx/habitat_utils.py#L152

 _callsign_present = False# check_callsign(serial)

I have been having issues with the habmodem app which I think is due to this issue, so I am happy that you are fixing it.

[darksidelemm]

Derp! You are absolutely correct... Have fixed this in 8761adb

[darksidelemm]

What is the issue you are encountering with 'habmodem'? (Is this the 'HAB Modem and Tracker' app for Android?)

[ED6E0F17]

I am using Matt`s Android app (HAB Modem and Tracker) for "offline" mapping, but after a while it would stop fetching new positions. I think this was due to the payload docs changing when other Trackers started uploading sondes that I was already tracking. The wind from Camborne has not come this way since you fixed the payload doc issue, but I expect this to be OK now.

I also tested the new upload method with a broken internet connection, and it coped well with the disconnection.

(I did find another issue with the Habmodem app if the time wraps over midnight.)