seisobs-webapp/scripts/mkGeolocationTable.py

#! /usr/bin/env python
# -*- coding: utf-8 -*-

'''
	Script to lookup city names of events with Nominatim service

	The input should be an valid quakeML file passed to stdin.
	The output will will be a javascript structure to be included in the
	SeisObs map service.

	The script should be updated regulary keep the total number of all
	AJAX calls to the Nominatim service small, e. g. :
	curl -s "https://ariadne.geophysik.ruhr-uni-bochum.de/fdsnws/event/1/query?minlat=50&maxlat=54&minlon=3&maxlon=10&minmag=1" | mkGeolocationTable.py > geolocationTable.js

	License
	Copyright 2014 Kasper D. Fischer <kasper.fischer@rub.de>

	This program is free software: you can redistribute it and/or modify it
	under the terms of the GNU General Public License as published by the Free
	Software Foundation, either version 3 of the License, or (at your option)
	any later version.

	This program is distributed in the hope that it will be useful, but
	WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
	or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
	for more details.

	You should have received a copy of the GNU General Public License along
	with this program. If not, see http://www.gnu.org/licenses/.

	$Id$
'''

# imports
try:
	import xml.etree.cElementTree as ET
except ImportError:
	import xml.etree.ElementTree as ET
from sys import stdin
import warnings
import urllib2 as URL
import json as JSON

# constants
namespaces = {'sc3': 'http://geofon.gfz-potsdam.de/ns/seiscomp3-schema/0.7',
	'qml': 'http://quakeml.org/xmlns/bed/1.2'}

# initialise variables
geolocationTable = {};

def simple_warning(message, category, filename, lineno, file=None, line=None):
	return 'Warning: %s\n' % (message)
warnings.formatwarning = simple_warning

# parse event.xml
DOM = ET.parse(stdin).getroot()

# iterate over all events
for event in DOM.iterfind('qml:eventParameters/qml:event', namespaces):
	publicID = event.attrib['publicID'].split('/')[2]
	lat = event.find('./qml:origin/qml:latitude/qml:value', namespaces).text
	lng = event.find('./qml:origin/qml:longitude/qml:value', namespaces).text
	url = 'https://open.mapquestapi.com/nominatim/v1/reverse.php?lat={0}&lon={1}&zoom=10&format=json'.format(lat, lng)
	# send and evaluate nominatim request
	response = URL.urlopen(url)
	if ( response.msg == 'OK' ):
		data = JSON.loads(response.read())
		try:
			try:
				city = data['address']['city']
			except:
				warnings.warn('Using county instead of city for event {0} at {1} N / {2} E (URL: {3})'.format(publicID, lat, lng, url))
				city = data['address']['county']
			country = data['address']['country']
			countryCode = data['address']['country_code'].upper()
			value = city
			if ( countryCode != 'DE' ):
				value = '{0} ({1})'.format(value, countryCode)
			geolocationTable[publicID] = value
		except:
			warnings.warn('Could not extract city for event {0} at {1} N / {2} E (URL: {3})'.format(publicID, lat, lng, url))
	else:
		warnings.warn('Request {0} failed'.format(url))
# dump json
print 'var geolocationTable = '+JSON.dumps(geolocationTable)+';'