Add an extra check for google credentials

If the user has a wrong base64 padded secret key the googlemaps
python library is returning "TypeError: Incorrect padding" which
is very hard to understand. So now we check if the secret key is
a valid base64 string

server/lib/python/cartodb_services/cartodb_services/google/exceptions.py

@@ -2,6 +2,8 @@
 # -*- coding: utf-8 -*-
 import json
 
+class InvalidGoogleCredentials(Exception):
+    pass
 
 class BadGeocodingParams(Exception):
     def __init__(self, value):

server/lib/python/cartodb_services/cartodb_services/google/geocoder.py

@@ -1,15 +1,18 @@
 #!/usr/local/bin/python
 # -*- coding: utf-8 -*-
 
+import base64
 import googlemaps
 
-from exceptions import MalformedResult
+from exceptions import MalformedResult, InvalidGoogleCredentials
 
 
 class GoogleMapsGeocoder:
     """A Google Maps Geocoder wrapper for python"""
 
     def __init__(self, client_id, client_secret, logger):
+        if not self._valid_credentials(client_secret):
+            raise InvalidGoogleCredentials('Invalid google secret key')
         self.client_id = self._clean_client_id(client_id)
         self.client_secret = client_secret
         self.geocoder = googlemaps.Client(
@@ -49,3 +52,13 @@ class GoogleMapsGeocoder:
     def _clean_client_id(self, client_id):
         # Consistency with how the client_id is saved in metadata
         return client_id.replace('client=', '')
+
+    def _valid_credentials(self, private_key):
+        try:
+            # Only fails if the string dont have a correct padding for b64
+            # but this way we could provide a more clear error than
+            # TypeError: Incorrect padding
+            base64.b64decode(private_key)
+            return True
+        except TypeError:
+            return False

server/lib/python/cartodb_services/cartodb_services/metrics/config.py

@@ -359,10 +359,10 @@ class GeocoderConfig(ServiceConfig):
         if self._geocoder_provider == self.NOKIA_GEOCODER:
             if not set(self.NOKIA_GEOCODER_REDIS_MANDATORY_KEYS).issubset(set(filtered_config.keys())) or \
             not self.heremaps_app_id or not self.heremaps_app_code:
-                raise ConfigException("""Some mandatory parameter/s for Nokia geocoder are missing. Check it please""")
+                raise ConfigException("""Heremaps app id or app code is not set up""")
         elif self._geocoder_provider == self.GOOGLE_GEOCODER:
             if self.GOOGLE_GEOCODER_API_KEY not in filtered_config.keys():
-                raise ConfigException("""Google geocoder need the mandatory parameter 'google_maps_private_key'""")
+                raise ConfigException("""Google geocoder private key is not set up""")
         elif self._geocoder_provider == self.MAPZEN_GEOCODER:
             if not self.mapzen_api_key:
                 raise ConfigException("""Mapzen config is not set up""")

server/lib/python/cartodb_services/setup.py

@@ -10,7 +10,7 @@ from setuptools import setup, find_packages
 setup(
     name='cartodb_services',
 
-    version='0.15.0',
+    version='0.15.1',
 
     description='CartoDB Services API Python Library',
 

server/lib/python/cartodb_services/test/test_googlegeocoder.py

@@ -6,9 +6,7 @@ import requests_mock
 from mock import Mock
 
 from cartodb_services.google import GoogleMapsGeocoder
-from cartodb_services.google.exceptions import BadGeocodingParams
-from cartodb_services.google.exceptions import NoGeocodingParams
-from cartodb_services.google.exceptions import MalformedResult
+from cartodb_services.google.exceptions import MalformedResult, InvalidGoogleCredentials
 
 requests_mock.Mocker.TEST_PREFIX = 'test_'
 
@@ -92,7 +90,8 @@ class GoogleGeocoderTestCase(unittest.TestCase):
     def setUp(self):
         logger = Mock()
         self.geocoder = GoogleMapsGeocoder('dummy_client_id',
-                                 'MgxyOFxjZXIyOGO52jJlMzEzY1Oqy4hsO49E', logger)
+                                           'MgxyOFxjZXIyOGO52jJlMzEzY1Oqy4hsO49E',
+                                           logger)
 
     def test_geocode_address_with_valid_params(self, req_mock):
         req_mock.register_uri('GET', self.GOOGLE_MAPS_GEOCODER_URL,
@@ -119,3 +118,9 @@ class GoogleGeocoderTestCase(unittest.TestCase):
                 searchtext='Calle Eloy Gonzalo 27',
                 city='Madrid',
                 country='España')
+
+    def test_invalid_credentials(self, req_mock):
+        with self.assertRaises(InvalidGoogleCredentials):
+            GoogleMapsGeocoder('dummy_client_id',
+                               'lalala',
+                               None)