Google Geocoding returns false address

Question

I am trying to geocode a bunch of zip codes to get their coordinates using the script below.
Since I'm mostly trying to convert German zip codes, I am using the country ISO code as prefix to make sure Google doesn't return US locations.

My data looks as follows:

DE-01099
DE-01108
DE-01109

These zip codes are near Dresden, Germany. Now, when looking up DE-01099 i.e. in GoogleMaps, it shows Dresden, as it should. Same thing, when I geocode it (http://maps.googleapis.com/maps/api/geocode/json?sensor=false&address=DE-01099), it returns "Dresden".

Searching for DE-01108 in GoogleMaps also shows Dresden, as supposed to. However, when geocoding this zip code, it returns Springfield, MA 01108, USA, even though I explicitely said DE-.

Any idea why / what to do?
Thanks in advance!

---

Script

import urllib
import sqlite3
import json
import time
import ssl

serviceurl = "http://maps.googleapis.com/maps/api/geocode/json?"

# Deal with SSL certificate anomalies Python > 2.7
# scontext = ssl.SSLContext(ssl.PROTOCOL_TLSv1)
scontext = None

conn = sqlite3.connect('geodata.sqlite')
cur = conn.cursor()

cur.execute('''
CREATE TABLE IF NOT EXISTS Locations (address TEXT, geodata TEXT)''')

fh = open("where2.data")
for line in fh:
    address = line.strip()
    print ''
    cur.execute("SELECT geodata FROM Locations WHERE address= ?", (buffer(address), ))

#    try:
#        data = cur.fetchone()[0]
#        print "Found in database ",address
#        continue
#    except:
#        pass

    print 'Resolving', address
    url = serviceurl + urllib.urlencode({"sensor":"false", "address": address})
    print 'Retrieving', url
    uh = urllib.urlopen(url, context=scontext)
    data = uh.read()
    print 'Retrieved',len(data),'characters',data[:20].replace('\n',' ')
    try:
        js = json.loads(str(data))
        # print js  # We print in case unicode causes an error
    except:
        continue

    if 'status' not in js or (js['status'] != 'OK' and js['status'] != 'ZERO_RESULTS') :
        print '==== Failure To Retrieve ===='
        print data
        break

    cur.execute('''INSERT INTO Locations (address, geodata)
            VALUES ( ?, ? )''', ( buffer(address),buffer(data) ) )
    conn.commit()
    time.sleep(0.5)

Answer 1

Please note that "DE-" prefix in address parameter doesn't apply any strict filter. If you need a strict filter you must use a component filtering as suggested by @geocodezip

Your request will have a form

https://maps.googleapis.com/maps/api/geocode/json?components=postal_code%3A01099%7Ccountry%3ADE&key=YOUR_API_KEY

So you say to geocoding service: "please find postal code 01099 in Germany".

Answer 2

You probably want to use component filtering on your request. Add &components=country:DE to the request rather than appending "DE-" to the zip code:

http://maps.googleapis.com/maps/api/geocode/json?address=01108&components=country:DE

returns the one result for Dresden:

{
   "results" : [
      {
         "address_components" : [
            {
               "long_name" : "01108",
               "short_name" : "01108",
               "types" : [ "postal_code" ]
            },
            {
               "long_name" : "Weixdorf",
               "short_name" : "Weixdorf",
               "types" : [ "political", "sublocality", "sublocality_level_1" ]
            },
            {
               "long_name" : "Dresden",
               "short_name" : "Dresden",
               "types" : [ "locality", "political" ]
            },
            {
               "long_name" : "Dresden",
               "short_name" : "DD",
               "types" : [ "administrative_area_level_2", "political" ]
            },
            {
               "long_name" : "Sachsen",
               "short_name" : "SN",
               "types" : [ "administrative_area_level_1", "political" ]
            },
            {
               "long_name" : "Germany",
               "short_name" : "DE",
               "types" : [ "country", "political" ]
            }
         ],
         "formatted_address" : "01108 Dresden, Germany",
         "geometry" : {
            "bounds" : {
               "northeast" : {
                  "lat" : 51.17815,
                  "lng" : 13.8371901
               },
               "southwest" : {
                  "lat" : 51.1285391,
                  "lng" : 13.742293
               }
            },
            "location" : {
               "lat" : 51.1443239,
               "lng" : 13.7997057
            },
            "location_type" : "APPROXIMATE",
            "viewport" : {
               "northeast" : {
                  "lat" : 51.17815,
                  "lng" : 13.8371901
               },
               "southwest" : {
                  "lat" : 51.1285391,
                  "lng" : 13.742293
               }
            }
         },
         "place_id" : "ChIJedA1NUPMCUcRsJIzlc6xIRw",
         "types" : [ "postal_code" ]
      }
   ],
   "status" : "OK"
}