HowFar2Home -- This is for mqttwarn https://github.com/jpmens/mqttwarn and Owntracks https://github.com/owntracks.

00readme.md

How Far 2 Home

This function was designed as a proof of concept and will return the estimated driving distance the device (using owntracks here) is from the GPS coordinates specified in the functions file

For example;

2014-03-24 15:45:00,484 INFO [log] matthew iphone is 38mins away from home

Requiements

• mqttwarn https://github.com/jpmens/mqttwarn
• Owntracks https://github.com/owntracks
• google api key, https://code.google.com/apis/console/ (With 'Distance Matrix API' turned ON)

NOTE's

• Unfortuantely it doesn't return the travel time including the current traffic! You need the 'google maps api for business' i believe to do this (need to confirm this!)
• As it has been pointed out.... (Use at own risk!)... Use of the Distance Matrix API must relate to the display of information on a Google Map; for example, to determine origin-destination pairs that fall within a specific driving time from one another, before requesting and displaying those destinations on a map. Use of the service in an application that doesn't display a Google map is prohibited. https://developers.google.com/maps/documentation/distancematrix/

I suggest looking at other map services api's and see if they have similar restrictions.

Future, or you could easily do it yourself

• Intergrate my other fucntion, reverse geo, https://gist.github.com/matbor/9381893
• change to another api that doesn't have the restriction that google maps does! Maybe checkout openstreetmap to see if it is ok!

functions.py

############################################################
###    OWNTRACKS -- Let me know how far from home I am    ##
###    by @bordignon on Twitter                           ##
############################################################

#needs urllib, json & time libraries
import time
import urllib
try:
    import json
except ImportError:
    import simplejson as json
    

def howfar2home(data):
    #beginging of settings
    #google maps api key, you need to enable distancematrix api
    googlemapapi = "xxxxxxxxxxxxxx"
    #destination coordinates for home location
    dest_lat = -37.813611
    dest_lng = 144.963056
    #end of settings

    #origin gps coordinates
    orig_lat = data.get('lat')
    orig_lng = data.get('lon')

    #using the gps cordinates here
    orig_coord = float(orig_lat), float(orig_lng)
    dest_coord = dest_lat, dest_lng
    epoch_time = int(time.time())

    urlforgps = "https://maps.googleapis.com/maps/api/distancematrix/json?origins={0}&destinations={1}&sensor=false&key={2}&departure_time={3}&mode=driving".format(str(orig_coord),str(dest_coord),str(googlemapapi),str(epoch_time))
    result= json.load(urllib.urlopen(urlforgps))
    driving_time = result['rows'][0]['elements'][0]['duration']['value']
    minutes2home = driving_time / 60
    data['time2home'] = minutes2home
    #return ('%s mins from home' % minutes)
    return "{username} {device} is {time2home}mins away from home".format(**data)
    
    
  ######
  #owntracks maps the topic name
  # THIS IS IN THE MQTTWARN sample functions file. You might not need this part.
def OwnTracksTopic2Data(topic):
    if type(topic) == str:
        try:
            # owntracks/username/device
            parts = topic.split('/')
            username = parts[1]
            deviceid = parts[2]
        except:
            deviceid = 'unknown'
            username = 'unknown'
        return dict(username=username, device=deviceid)
    return None

mqwarn.ini

[owntracks-howfar2home]
topic = owntracks/+/+
targets = log:info
datamap = OwnTracksTopic2Data()
format  = howfar2home()
title = How far 2 home