Welcome!

You will be redirected in 30 seconds or close now.

ColdFusion Authors: Yakov Fain, Jeremy Geelan, Maureen O'Gara, Nancy Y. Nee, Tad Anderson

Related Topics: ColdFusion

ColdFusion: Article

An In-Depth Look at Mapping APIs

The benefits and drawbacks

Back in the November 2005 issue of CFDJ, we looked at how to create a live map of your Web site visitors using Google Maps and other freely available services.

Now that Yahoo! and Microsoft have joined the fray and released their own mapping APIs, we'll revisit our example while learning about each implementation along the way. All of these APIs are extremely powerful, but each has its own advantages that may work better for your particular solution. We'll take a look at each in detail and outline some of the benefits and drawbacks of each.

Geo-locating by IP Address
Let's go over our example one more time. We're going to use these tools to create a visual map of users visiting your site. You'll be able to show these on a custom map along with any other text or HTML data you'd like to display. One of the key ingredients to this technique is the ability to geo-locate an IP address. This refers to the ability to locate a user's geographic latitude and longitude from his IP address. The most cost-effective source of this information is to query one of the freely available public databases. NetGeo was a project originally set up by the Cooperative Association for Internet Data Analysis (CAIDA). Although it has been defunct for several years, the database is still freely available and provides a good resource for determining rough locations.

We'll set up a table (see Listing 1) to keep a log of user visits. Each time a new user visits the site, we'll query the geolocation database and insert a record of the user's IP address, latitude, longitude, city, state, country. In CFMX 7, this code can be put inside the onSessionStart() function in Application.cfc.

Queries are executed via HTTP against the NetGeo database by calling the URL http://netgeo.caida.org/perl/netgeo.cgi?target=64.19.164.74. It will return the following data to the browser:

VERSION=1.0
TARGET: 64.19.164.74
NAME: MONMOUTH-BLK2
NUMBER: 64.19.128.0 - 64.19.191.255
CITY: RED BANK
STATE: NEW JERSEY
COUNTRY: US
LAT: 40.35
LONG: -74.08
LAT_LONG_GRAN: City
LAST_UPDATED: 01-Jun-2001
NIC: ARIN
LOOKUP_TYPE: Block Allocation
RATING:
DOMAIN_GUESS: MONMOUTH.COM
STATUS: OK

ColdFusion's string functions can be used to parse out the relevant latitude and longitude data, as well as the city, state, and country. We'll then insert that info into the database and use it to populate a map overlay when each point is clicked. Listing 2 contains the code to parse out these fields.

Another source of freely available geo-location data is the community-based hostip.info project located at http://www.hostip.info. Although this is a newer database, it's being actively and continuously updated and is improving with time. This database can also be queried via HTTP and returns the results in a format similar to NetGeo. A URL query to hostip.info would be structured as http://api.hostip.info/get_html.php?ip=64.19.164.74&position=true.

You can also download the full hostip.info database directly to your server for quicker response time. There's also the commercial GeoIP City database maintained by MaxMind (see www.maxmind.com/app/city).

Drawing the Map Using Google
The first thing you'll need to do is to sign up for a Google Maps API key at www.google.com/apis/maps/. This key will have to be included on any pages on which you'll be drawing maps.

To begin, put the script calls in Listing 3 in the <head></head> section of your page.

Next, include an empty div right after your <body> tag. This will contain the actual map and determine its size:

<div id="map" style="width: 700px; height: 500px"></div>

Using Yahoo!'s New Flex-Based API
You'll also have to get an application ID from Yahoo! before using its service. Once that's done, you'll put script calls in Listing 4 in the <head></head> section of your page.

Then include an empty div right after your <body> tag. This div will contain the actual map:

<div id="mapContainer" style="width: 700px; height: 500px"></div>

Microsoft's Virtual Earth Implementation
Interfacing with Microsoft's Virtual Earth is also relatively painless. Most of your code will go in the <head></head> section of the page. The code you'll need to include is in Listing 5. Then you'll have to add an onLoad call to your body tag as follows: <body onLoad="OnPageLoad()">.

As with most of Microsoft's technologies, Virtual Earth will probably take a few revisions before they get it right. Currently there are advantages to using the Google or Yahoo! APIs. Google offers simplicity and the capability to add detailed HTML overlays complete with images. Yahoo!'s advantage comes in its rich integration possibilities with Flash-based technologies as well as AJAX.

Troubleshooting
One thing to note is that some browsers will throw a security error when trying to access a JavaScript file from a different domain. You can get around this by downloading the .js file to your server and serving it up locally.

Taking It Even Further
The Yahoo! map that we built, though Flash-based, used the JavaScript API to interact with the map. There's also an ActionScript API available for direct integration with Flash as well as a Flex API to interact with maps directly from your RIAs. This comes at a great time with Macromedia's recent announcements regarding the Flex product line. Check this link under resources for a great example of what can be done with the Flash API: http://tinyurl.com/avpv8 (from Justin's Rich Media Blog). The APIs will also accept geo-coded RSS feeds. This lets you fuse live data right on to your maps, such as being able to plot apartments currently listed for rent through craigslist.

Conclusion
We've only scratched the surface of what can be done using the new mapping APIs that are now available. It's possible to create all kinds of applications based on geographic data. Although the licensing terms for each API are slightly different, they are generally pretty liberal and even allow for commercial use in some cases. Visit the links provided for full documentation on each of them.

Resources

More Stories By Joe Danziger

Joe Danziger is a senior web applications developer with Multimax, Inc., a provider of Enterprise IT Services and Solutions supporting the critical missions of the Air Force, Army, Navy, and other Department of Defense components. He is certified as an Advanced Macromedia ColdFusion MX Developer, and also maintains the Building Blocks site (www.ajaxcf.com) dedicated to AJAX and ColdFusion, as well as DJ Central (www.djcentral.com), a Website serving DJs and the electronic dance music industry.

Comments (0)

Share your thoughts on this story.

Add your comment
You must be signed in to add a comment. Sign-in | Register

In accordance with our Comment Policy, we encourage comments that are on topic, relevant and to-the-point. We will remove comments that include profanity, personal attacks, racial slurs, threats of violence, or other inappropriate material that violates our Terms and Conditions, and will block users who make repeated violations. We ask all readers to expect diversity of opinion and to treat one another with dignity and respect.


IoT & Smart Cities Stories
Every organization is facing their own Digital Transformation as they attempt to stay ahead of the competition, or worse, just keep up. Each new opportunity, whether embracing machine learning, IoT, or a cloud migration, seems to bring new development, deployment, and management models. The results are more diverse and federated computing models than any time in our history.
At CloudEXPO Silicon Valley, June 24-26, 2019, Digital Transformation (DX) is a major focus with expanded DevOpsSUMMIT and FinTechEXPO programs within the DXWorldEXPO agenda. Successful transformation requires a laser focus on being data-driven and on using all the tools available that enable transformation if they plan to survive over the long term. A total of 88% of Fortune 500 companies from a generation ago are now out of business. Only 12% still survive. Similar percentages are found throug...
Japan DX Pavilion at @CloudEXPO Silicon Valley
In his general session at 19th Cloud Expo, Manish Dixit, VP of Product and Engineering at Dice, discussed how Dice leverages data insights and tools to help both tech professionals and recruiters better understand how skills relate to each other and which skills are in high demand using interactive visualizations and salary indicator tools to maximize earning potential. Manish Dixit is VP of Product and Engineering at Dice. As the leader of the Product, Engineering and Data Sciences team at D...
The graph represents a network of 1,329 Twitter users whose recent tweets contained "#DevOps", or who were replied to or mentioned in those tweets, taken from a data set limited to a maximum of 18,000 tweets. The network was obtained from Twitter on Thursday, 10 January 2019 at 23:50 UTC. The tweets in the network were tweeted over the 7-hour, 6-minute period from Thursday, 10 January 2019 at 16:29 UTC to Thursday, 10 January 2019 at 23:36 UTC. Additional tweets that were mentioned in this...
At CloudEXPO Silicon Valley, June 24-26, 2019, Digital Transformation (DX) is a major focus with expanded DevOpsSUMMIT and FinTechEXPO programs within the DXWorldEXPO agenda. Successful transformation requires a laser focus on being data-driven and on using all the tools available that enable transformation if they plan to survive over the long term. A total of 88% of Fortune 500 companies from a generation ago are now out of business. Only 12% still survive. Similar percentages are found throug...
Where many organizations get into trouble, however, is that they try to have a broad and deep knowledge in each of these areas. This is a huge blow to an organization's productivity. By automating or outsourcing some of these pieces, such as databases, infrastructure, and networks, your team can instead focus on development, testing, and deployment. Further, organizations that focus their attention on these areas can eventually move to a test-driven development structure that condenses several l...
The term "digital transformation" (DX) is being used by everyone for just about any company initiative that involves technology, the web, ecommerce, software, or even customer experience. While the term has certainly turned into a buzzword with a lot of hype, the transition to a more connected, digital world is real and comes with real challenges. In his opening keynote, Four Essentials To Become DX Hero Status Now, Jonathan Hoppe, Co-Founder and CTO of Total Uptime Technologies, shared that ...
Over the course of two days, in addition to insightful conversations and presentations delving into the industry's current pressing challenges, there was considerable buzz about digital transformation and how it is enabling global enterprises to accelerate business growth. Blockchain has been a term that people hear but don't quite understand. The most common myths about blockchain include the assumption that it is private, or that there is only one blockchain, and the idea that blockchain is...
Never mind that we might not know what the future holds for cryptocurrencies and how much values will fluctuate or even how the process of mining a coin could cost as much as the value of the coin itself - cryptocurrency mining is a hot industry and shows no signs of slowing down. However, energy consumption to mine cryptocurrency is one of the biggest issues facing this industry. Burning huge amounts of electricity isn't incidental to cryptocurrency, it's basically embedded in the core of "mini...