Thought Delimited

Every April, the University of Maryland holds a huge open-house event called Maryland Day that draws 60,000+ visitors to the campus to view exhibits highlighting the research conducted at the university and participate in various events and activities. All of the event details are entered into a ColdFusion application, and one of those details is the GPS coordinates (latitude and longitude) of where each event is taking place so visitors to the website can see where the events are located on Google Maps.

Now that smartphones are becoming more prevalent, I wanted to see if it was possible to build a web application that would show the user where they were currently located and then show them on a map how to get from their current location to a particular event.

So I did some research and learned that HTML 5 comes with a Geolocation API. This API allows you to execute Javascript functions within the navigator.geolocation object built into the browser that retrieve the supposed latitude and longitude coordinates of where the browser is located (and, if available, the altitude, heading, and speed at which the browser is moving).

Using the code examples I found on the Gelocation API page on the W3C website and on Oliver Wehren's geolocation demo page, I was able to create my own test page for determining my location and marking it on Google Maps. I then tried using the page with my Motorola Droid, my iPod Touch, and my manager's iPhone.

The default web browsers on all three devices implemented the Geolocation API (my preferred browser on my Droid, the Dolphin Browser, did not). Each of the browsers displayed a confirmation dialog asking for permission to share my location information with the web page (as mandated by the standard), and once I permitted the information to be used, my test page was able to place a marker denoting my location on the map.

However, the location wasn't as accurate as I had hoped. Although the API was coded to accept location data from the on-board GPS system in a mobile device, neither the iPhone nor the Droid seem to provide GPS data to the browser. If I was connected to the campus wireless network, my location was determined via the network topography, and it could be off by as much as 150 feet or so. The accuracy was even worse if I was relying solely on 3G: in that scenario, but the iPhone and the Droid had me located on the side of a state road on the outskirts of campus, a good twenty minute walk from where I actually was. I have no idea what caused both devices to pick that particular spot, as there certainly wasn't a cell tower anywhere near that location.

So I came to the conclusion that while the Geolocation API could be used to determine what town, city, or general area a user was currently in, it wasn't accurate enough (at least with these browsers in these devices) to provide walking or driving directions within a small area, especially given the fact that many of the users for the service I had in mind would only have access to the Internet via a 3G connection.

But if someone knows of a way of increasing the location accuracy of the Geolocation API, a way that doesn't require the end-user to modify their mobile browser in order to make it work, I'd love to hear about it.

I happened to stumble across a blog post today by Phil Haack with the title "Death to confirmation dialogs with jquery.undoable." In it, Phil explained how he was inspired to write his plugin by seeing how his Netflix queue allowed him to "undo" the deletion of an item from the queue. As he said in his post:

"Notice that thereﾒs no confirmation dialog that Iﾒm most likely to ignore questioning my intent requiring me to take yet one more action to remove the movie. No, the movie is removed immediately from my queue just as I requested. I love it when software does what I tell it to do and doesnﾒt second guess me!"

His post got my attention because I'm currently in the middle of designing a scaffolding/code generation system, specifically to output pages for performing CRUD (Create, Read, Update, Delete) tasks, and it's currently designed so that when the user clicks on a "delete" link for a record (and Javascript is enabled), I make the user confirm their decision via a customizable dialog box (via the jqModal jQuery plugin) before proceeding with the deletion.

So I got to thinking about what would be involved in doing what he was suggesting: allowing the user to "delete" a record without confirmation as long as they had the option of undoing that action while still on the page.

I put "delete" in quotation marks because such a process would almost certainly involve making the delete a "soft" delete: marking/tagging the record as being deleted but not actually deleting the underlying database record. Undoing an actual deletion would be much harder, given that you would lose the unique record id in the deletion in addtion to the rest of the record data. I suppose you could potentially store the data from the record client-side (in the page) so the "undo" record could recreate the record from scratch, but that would be a pain and might not be feasible in every scenario. Undoing a soft delete/changing the delete flag in the record, on the other hand, would be pretty easy.

But if I went the soft delete routine, then the question would become: how do those records get deleted for real? I tend to design my web applications with a long term view, and I don't want the application database tables to fill up with deleted records over a number of years. My clients typically only have access to the database tables via the application itself, so leaving that up to them is not an option. So I would either have to given them another page/tool in the web application (perhaps a tool restricted to a tech-savvy few) to actually remove the deleted records, or perhaps run a scheduled task to remove those database records that have been marked for deletion for a year or more.

After some consideration, my current inclination is to stay with my current confirmation dialog/deletion routine. In most of my applications, the CRUD interactions are reserved for the administrative users of the application, who typically know when it's appropriate to delete a record. And the need to delete a record via the CRUD tools provided is usually rare, so having a confirmation dialog come up for each instance isn't too much of an annoyance.

But I'd be curious to hear other people's thoughts on this topic.

I just finished a project that included an administrative page where users could make changes to a parent record and numerous child records via multiple forms. All of the form submissions were done via AJAX, so I needed a way to illustrate which of the forms on the page contained changed or "dirty" data, and which forms had no unsaved changes.

This dirtyFields plugin is derived from the functions I wrote to handle that task in that project.

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If you've been following my updates on Twitter, you know that I was at the CFUnited conference last week. I didn't post anything during the conference because, quite frankly, I didn't set aside any time to do so, and there was lot going on most of the time.

I'm not going to try and sum up everything that was presented at the conference: I'm not sure any one person can. But there were a number of news items and developments that came about either just before the conference or during the conference that I thought were worth pointing out:

• ColdFusion 9 in the Cloud: In the opening CFUnited keynote, Ben Forta and the Adobe team announced that ColdFusion 9 would include licensing options for running ColdFusion in cloud environments, and that they would specifically support the use of ColdFusion 9 on Amazon's EC2 cloud environment. Details (sparse though they are) can be found on Ben's blog post on the subject. Though I'm not a fan boy of cloud computing, having this option is important for ColdFusion developers who have an idea for a high-traffic web application but don't have the money to invest in their own server farm.
  
  
• 4CFF: 4CFF is the acronym for the For ColdFusion Foundation, a new non-profit foundations founded by several member of the CF community with the goal of providing assistance and resources to ColdFusion open-source projects and establishing a "professional membership society for the ColdFusion Community at large." I missed their unofficial announcement/presentation, so I can't provide any information about how they plan to move forward with their goals, but I think the idea of having a resource where CF programmers can get help with the non-programming challenges involved in starting and maintaining an open-source project is a good one.
  
  
• Framework updates/changes: The final, production version of Model-Glue 3.0 (Gesture) was released just prior to the conference, while the beta release of ColdBox 3.0 was announced on the first day of the conference. But perhaps the most dramatic framework announcement was that Adam Haskell, previously the lead developer for the Fusebox framework, was going to resign from that role and lead the development of a new and separate version of Fusebox called FuseNG (Fusebox Next Generation), citing irreconcilable difference between himself and TeraTech, the Maryland-based CF development/training shop that currently controls the domain name and source code behind Fusebox. As a developer who uses Fusebox, I'm curious to see how this decision will play out. The current version of Fusebox is a very effective, usable, and mature framework, but Adam's a smart guy and it'll be interesting to see what he and the other developers involved in FuseNG will come up with.
  
  
• The Merlin Manager beta: The final event on Friday at the conference was the Demo Derby, where developers got several minutes to show off a project of theirs. While all of the presentations were noteworthy (and in two instances quite humorous), the one I thought really needed to be brought to the attention of the CF community as a whole was John Mason's Merlin Manager. One of the announcements regarding ColdFusion 9 was that it would provide an AIR-powered desktop application that would let ColdFusion server administrators manage and compare multiple ColdFusion server instances from one dashboard. John's Merlin Manager is also an AIR-powered CF server manager, but it's built to work with ColdFusion 7 and 8 servers. He demonstrated how his app provided real-time status information for a server, how it let you store current server settings as a snapshot prior to making a settings change, and that it could compare the settings between two different servers, highlighting where the settings differed. Even though the project is still in beta, it looked very feature-complete and could be of real benefit to those CF shops that won't be upgrading to CF 9 anytime soon. John is looking for volunteers to participate in evaluating the beta: if you're interested, visit http://www.merlinmanager.com/ to sign up.

As for the conference as a whole, I have to echo everyone who's already commented about it on their blogs and via Twitter: it was an excellent, informative, and fun conference, the best I've ever attended. And that statement is coming from someone who, for various personal and professional reasons, wasn't all that worked up about attending. Everyone involved in the planning and execution of the conferences, especially the folks from Stellr and those presenters who stepped up to fill in for last-minute speaker cancellations (all the presenters deserve credit, but those folks especially) should be proud of the work they did.

For those folks who weren't able to attend, be aware that a number of the presenters will be posting their presentations online, either on their own blogs, SlideSix, or both, so keep an eye out for announcements about those (and note that some of those posting and announcements were made last week during the conference itself).

One of my favorite podcasts is Buzz Out Loud, a weekday live video stream and podcast from CNET.com that reports, analyzes, and banters about the tech news of the day. This past week, they conducted an interview with Federal CTO Aneesh Chopra, which I just finished listening to today.

The entire interview was quite interesting, but there were two particular discussions that struck me.

The first one was about broadband penetration: the Buzz Out Loud podcasters wanted to know what plans, if any, were being made to promote the rollout of broadband to those areas where such service was limited or unavailable. Chopra said that they hoped to address that issue with a national broadband plan due to be revealed in February 2010, but he said that his personal focus was more on encouraging innovation in developing applications that would further the adoption and development of a robust broadband infrastructure. In other words, it's not just about building the infrastructure for people, businesses, and government organizations to have, but creating compelling applications of that infrastructure that bring people on board and give them more reasons for wanting ubiquitous Internet access.

As web/Internet application developers, we tend to think of broadband, high bandwith, and Internet access as the infrastructure that allows us to build robust applications. It's kind of exciting to look at it the other way around, that creating useful, effective, compelling applications that people want (or perhaps even need) could promote and justify the expanse of the broadband infrastructure.

The second discussion was in response to a viewer question about the use of open source software within government agencies (SUSE and RedHat were specifically mentioned). Chopra said that that was really in the federal CIO's arena of concern, but that he personally was more interested in promoting the principles of "open collaboration" and the "sharing of intellectual property as we build value." He went on to explain that what he meant by that was that he didn't care so much if an application built for the government was built on a proprietary platform so long as that application became shared intellectual property between government agencies. That again was another point that I hadn't heard anyone make before.

I'd encourage anyone who has an interest in how the federal government hopes to leverage technology to the country's advantage to listen to this podcast episode. You can watch the video version or listen to the audio version, either streaming or as a download, at the following address:

http://www.cnet.com/8301-19709_1-10302978-10.html?tag=mncol;title