Geolocation - HTML5 - page 166

file by reading the IP address that made the HTTP request, doing the IP-to-location
translation on the server side, and then outputting the results.
In addition to latitude and longitude, the location data shown in Table 8-1 is available.

Table 8-1. Location data examples from MaxMind geoip.js

Method Description Example data

geoip_country_code() Country Code US

geoip_country_name() Country Name United States

geoip_city() City Minneapolis

geoip_region_name() Region MN

geoip_region_name() Region Name Minnesota

geoip_postal_code() Postal Code 55401

geoip_area_code() Telephone Area Code 612

geoip_metro_code() Metro Code 613

The free version of MaxMind requires attribution in the form of a link back to the
website, so the isMaxMind parameter has been added to the printLatLong() function to
indicate that MaxMind was used to get the location:
function printLatLong(latitude, longitude, isMaxMind) {
$('body').append('<p>Lat: ' + latitude + '</p>');
$('body').append('<p>Long: ' + longitude + '</p>');
// if we used MaxMind for location, add attribution link
if (isMaxMind) {
$('body').append('<p><a href="http://www.maxmind.com" target="_blank">IP
to Location Service Provided by MaxMind</a></p>');
}
}

Another scenario to be mindful of is if the user denies your request for
location information or something else goes wrong. To handle this
eventuality, set up the geo_error handler to also fall back to using IP-
to-location translation, as shown in the next recipe.

Because we've added MaxMind as a fallback, this solution is able to handle a larger
percentage of browsers and devices without having to rely on native geolocation sup-
port in the browser.

See Also
MaxMind provides free/open source geolocation solutions for city, country, and IP
lookups at http://www.maxmind.com/app/ip-location .