Google Maps: how to get country, state/province/re

Question

I need a list of countries, states & cities based on a collection of lat/long values I have. I need to store this information in a manner that hierarchy is preserve and without duplicates (e.g. "USA" and "United States" and "United States of America" are the same country; I only want one instance of this country in my database).

Is this possible to do with Google Map API?

Answer 1

I wrote this function that extracts what you are looking for based on the address_components returned from the gmaps API. This is the city (for example).

export const getAddressCity = (address, length) => {
  const findType = type => type.types[0] === "locality"
  const location = address.map(obj => obj)
  const rr = location.filter(findType)[0]

  return (
    length === 'short'
      ? rr.short_name
      : rr.long_name
  )
}

Change locality to administrative_area_level_1 for the State etc.

In my js code I am using like so:

const location =`${getAddressCity(address_components, 'short')}, ${getAddressState(address_components, 'short')}`

Will return: Waltham, MA

Answer 2

@Szkíta Had a great solution by creating a function that gets the address parts in a named array. Here is a compiled solution for those who want to use plain JavaScript.

Function to convert results to the named array:

function getAddressParts(obj) {

    var address = [];

    obj.address_components.forEach( function(el) {
        address[el.types[0]] = el.short_name;
    });

    return address;

} //getAddressParts()

Geocode the LAT/LNG values:

geocoder.geocode( { 'location' : latlng }, function(results, status) {

    if (status == google.maps.GeocoderStatus.OK) {
        var addressParts =  getAddressParts(results[0]);

        // the city
        var city = addressParts.locality;

        // the state
        var state = addressParts.administrative_area_level_1;
    }

});

Answer 3

I used this question as a starting point for my own solution. Thought it was appropriate to contribute my code back since its smaller than tabacitu's

Dependencies:

• underscore.js
• https://github.com/estebanav/javascript-mobile-desktop-geolocation
• <script src="https://maps.googleapis.com/maps/api/js?v=3.exp&sensor=false"></script>

Code:

if(geoPosition.init()){  

    var foundLocation = function(city, state, country, lat, lon){
        //do stuff with your location! any of the first 3 args may be null
        console.log(arguments);
    }

    var geocoder = new google.maps.Geocoder(); 
    geoPosition.getCurrentPosition(function(r){
        var findResult = function(results, name){
            var result =  _.find(results, function(obj){
                return obj.types[0] == name && obj.types[1] == "political";
            });
            return result ? result.short_name : null;
        };
        geocoder.geocode({'latLng': new google.maps.LatLng(r.coords.latitude, r.coords.longitude)}, function(results, status) {
            if (status == google.maps.GeocoderStatus.OK && results.length) {
                results = results[0].address_components;
                var city = findResult(results, "locality");
                var state = findResult(results, "administrative_area_level_1");
                var country = findResult(results, "country");
                foundLocation(city, state, country, r.coords.latitude, r.coords.longitude);
            } else {
                foundLocation(null, null, null, r.coords.latitude, r.coords.longitude);
            }
        });
    }, { enableHighAccuracy:false, maximumAge: 1000 * 60 * 1 });
}

Answer 4

What you are looking for is called reverse geocoding. Google provides a server-side reverse geocoding service through the Google Geocoding API, which you should be able to use for your project.

This is how a response to the following request would look like:

http://maps.googleapis.com/maps/api/geocode/json?latlng=40.714224,-73.961452&sensor=false

Response:

{
  "status": "OK",
  "results": [ {
    "types": [ "street_address" ],
    "formatted_address": "275-291 Bedford Ave, Brooklyn, NY 11211, USA",
    "address_components": [ {
      "long_name": "275-291",
      "short_name": "275-291",
      "types": [ "street_number" ]
    }, {
      "long_name": "Bedford Ave",
      "short_name": "Bedford Ave",
      "types": [ "route" ]
    }, {
      "long_name": "New York",
      "short_name": "New York",
      "types": [ "locality", "political" ]
    }, {
      "long_name": "Brooklyn",
      "short_name": "Brooklyn",
      "types": [ "administrative_area_level_3", "political" ]
    }, {
      "long_name": "Kings",
      "short_name": "Kings",
      "types": [ "administrative_area_level_2", "political" ]
    }, {
      "long_name": "New York",
      "short_name": "NY",
      "types": [ "administrative_area_level_1", "political" ]
    }, {
      "long_name": "United States",
      "short_name": "US",
      "types": [ "country", "political" ]
    }, {
      "long_name": "11211",
      "short_name": "11211",
      "types": [ "postal_code" ]
    } ],
    "geometry": {
      "location": {
        "lat": 40.7142298,
        "lng": -73.9614669
      },
      "location_type": "RANGE_INTERPOLATED",
      "viewport": {
        "southwest": {
          "lat": 40.7110822,
          "lng": -73.9646145
        },
        "northeast": {
          "lat": 40.7173774,
          "lng": -73.9583193
        }
      }
    }
  },

  ... Additional results[] ...

You can also opt to receive the response in xml instead of json, by simply substituting json for xml in the request URI:

http://maps.googleapis.com/maps/api/geocode/xml?latlng=40.714224,-73.961452&sensor=false

As far as I know, Google will also return the same name for address components, especially for high-level names like country names and city names. Nevertheless, keep in mind that while the results are very accurate for most applications, you could still find the occasional spelling mistake or ambiguous result.

Answer 5

I found the GeoCoder javascript a little buggy when I included it in my jsp files.

You can also try this:

    var lat = "43.7667855" ;
    var long = "-79.2157321" ;
    var url = "https://maps.googleapis.com/maps/api/geocode/json?latlng="
       +lat+","+long+"&sensor=false";
    $.get(url).success(function(data) {
       var loc1 = data.results[0];
       var county, city;
         $.each(loc1, function(k1,v1) {
            if (k1 == "address_components") {
               for (var i = 0; i < v1.length; i++) {
                  for (k2 in v1[i]) {
                     if (k2 == "types") {
                        var types = v1[i][k2];
                        if (types[0] =="sublocality_level_1") {
                            county = v1[i].long_name;
                            //alert ("county: " + county);
                        } 
                        if (types[0] =="locality") {
                           city = v1[i].long_name;
                           //alert ("city: " + city);
                       } 
                     }

                  }          

               }

            }

         });
         $('#city').html(city); 
    }); 

Answer 6

I've created a small mapper function:

private getAddressParts(object): Object {
    let address = {};
    const address_components = object.address_components;
    address_components.forEach(element => {
        address[element.types[0]] = element.short_name;
    });
    return address;
}

It's a solution for Angular 4 but I think you'll get the idea.

Usage:

geocoder.geocode({ 'location' : latlng }, (results, status) => {
    if (status === google.maps.GeocoderStatus.OK) {
        const address = {
            formatted_address: results[0].formatted_address,
            address_parts: this.getAddressParts(results[0])
        };
        (....)
    }

This way the address object will be something like this:

address: {
    address_parts: {
        administrative_area_level_1: "NY",
        administrative_area_level_2: "New York County",
        country: "US",
        locality: "New York",
        neighborhood: "Lower Manhattan",
        political: "Manhattan",
        postal_code: "10038",
        route: "Beekman St",
        street_number: "90",
    },
    formatted_address: "90 Beekman St, New York, NY 10038, USA"
}

Hope it helps!