I needed a quick, perhaps even sloppy way to output an array as XML. Some Googling turned up a few tools, including Simon Willison’s XmlWriter, Johnny Brochard’s Array 2 XML, Roger Veciana Associative array to XML, and Gijs van Tulder’s Array to XML. Finally, Gijs also pointed me to the XML_Serializer PEAR Package.

In an example of how even the smallest barriers can turn people away, I completely ignored the two possible solutions at PHP Classes, because navigating and using the site sucks. I passed on Willison’s function because, well, it didn’t look like it would do enough of what I wanted. Despite Gijs’ recommendation of the PEAR module, I was happy enough to use his array_to_xml function, as it did what I needed and required the lest work for the moment. I may revisit XML_Serializer sometime, but…

array, array to xml, php, xml, XML_Serializer

I’m honored to join Katie Bauer, of Yale University Library, in a program coordinated by Mary Jane Kelsey, of Yale Law’s Lillian Goldman Library.

The full title of our program is Technology Scouts: how to keep your library and ILS current in the IT world (H-4, 4PM Tuesday, room 274). My portion of the presentation will focus on how we’re fixing up our catalogs, with a big emphasis on how APIs can be used to continuously reinvent the way we look at — and thus understand and use — the information we have. The big idea here is that as we separate the systems that store and manage our data from the applications that display and manipulate it, we open the door to faster, cheaper development — and make room for a bunch of new ideas along the way.

Because it’s a short program, I’ll only be able to gloss over some of the discussion of what’s wrong with our catalogs and how we’re fixing them, and while there’s a lot to say about WPopac, I’ll have to leave it to Jenny Levine to explain most of it.

My slides are online. As usual, all the underlined text is hotlinked along with all the screenshots, so click them for more information and detail.

AALL, AALL2006, American Association of Law Libraries, api, conference, law libraries, lib20, libraries, library, library 2.0, opensearch, presentation, rss, web 2.0, web20, xml

I didn’t hear big announcement of it, but deep in the docs (? PHP 5.1.0) you’ll find a note about additional Libxml parameters. In there you’ll learn about “LIBXML_NOCDATA,” and it works like this:

simplexml_load_string($xmlraw, 'SimpleXMLElement', LIBXML_NOCDATA);

Without that option (and with all previous versions of PHP/SimpleXML), SimpleXML just ignores any < ![CDATA[...]]> ‘escaped’ content, such as you’ll find in most every blog feed.

cdata, cdata in php, fixed, parsing rss, php, php5, rss, simplexml, xml

No, I’m not talking about the interface our users see in the web browser — there’s enough argument about that — I’m talking about web services, the technologies that form much of the infrastructure for Web 2.0.

Once upon a time, the technology that displayed a set of data, let’s say catalog records, was inextricably linked to the technology that stored that set of data. As we started to fill our data repositories, we found it usefull to import (and export) the data so that we could benefit from the work others had done and share our contributions with others. These processes were manual, or at least actively managed, and they depended on the notion that we had to have that information in our servers to be used by and displayed for our users.

Then technology evolved. Many applications now separate the components that store and manage the information from the components that display and manipulate it, and a few applications open up their data stores to the public via web services-based APIs. This is the concept that makes HousingMaps, ChicagoCrime, and Flickr Colr Pickr, among so many others, work.

Think about this for a moment: Our ILSs are inventory management systems, but our OPACs are (supposed to be) search and retrieval systems. The difference is obvious from here, but our vendors continue to operate as though you can’t have one without the other.

It might be easier to illustrate this point with an example or two.

Amazon Light is one of hundreds of applications based on Amazon’s web services. It connects Amazon’s inventory system with a custom built search and retrieval system, and it works. The Amazon Lite developers at Kokogiak didn’t need to build the inventory system, they only needed to think about ways to make the Amazon inventory more useful to you. Try it out, you might like the ability to search your local library (via some real hacks) or bookmark things via del.icio.us.

Or, you might not. Because Amazon allows anybody to access their catalog data, everybody has the opportunity to build a better, more usable catalog — or any other application that can benefit from the bibliographic details in it.

Take LibraryThing for example. It’s hard to explain what it is about people who read books that makes them want to list the books they own or have read or are interested in reading, but LibraryThing doesn’t worry about the why. It just answers the need. And because listing books, at least making a detailed list of books, can be time consuming, LibraryThing makes it easier by fetching the full details and book jacket from Amazon’s catalog. LibraryThing doesn’t need to “own” that info, it just needs access to it.

And what’s interesting is that LibraryThing is only one of a number of similar applications. Take a look at AllConsuming, Technorati’s popular books, and listal. These services connect Amazon’s catalog data with other data gathered from users or from web crawls, then they share the results. Here’s Ryan Eby’s lists of owned and wanted books, and here they are in RSS. Why RSS? Take a look at how he’s using the listal feed for his current reading list in his blog (lower-right column).

These are not technology demos. These are real applications. They are examples of how the world changes when you open up access to your catalog data. It’s what happens when we realize that the tools that store and manage our information are separate from the tools that display and manipulate that information.

Obviously, I’m about to make the (now-old) argument that we need to open our OPACs like this, but we also need take the lesson that easy and loose is winning over detailed and difficult — even in XML representations of our catalog data. And after looking at all that’s been done so far, I want to ask: why not adopt Amazon’s web services XML schema?

Is it so bad that it was invented elsewhere? Is it a bad thing that there are perhaps hundreds of applications that are already using data in that format?

Maybe the answer to those questions is yes, but here’s where technology can serve us again: we don’t have to choose. We don’t need to bet on one technology while we watch others progress faster. Our systems can output the same catalog data in any number of different ways. RSS, OpenSearch, MARC-XML, ATOM, EAD, or DC are all possible, easy in fact — if the inventory server architecture is open enough to allow it.

What do I really mean when I say library web services should be like Amazon web services? I mean they should be that accessible, that usable, that hackable. I mean libraries will benefit when people we’ve never met are spending their evenings building new applications to use our data. People are wondering how to get more programmers in libraries (example one, two), but I’m wondering how to make library systems more programmer friendly.

Fired up? Read more with my library catalogs should be like WordPress post, John Blyberg’s ILS customer bill of rights, and Ryan Eby’s open vs. turnkey discussion.

tags: amazon, amazon api, amazon web services, api, dublin core, ead, libraries, library, library catalog, marc, marc-xml, opac data, opensearch, web 2.0, web service, web services, web20, webservice, webservices, xml, xml server

Everybody likes documentation. The Zend folks posted this overview and SimpleXML introduction The O’Reilly folks at ONLamp offered this guide to using SimpleXML. Of course, there’s always the SimpleXML docs at PHP.net.

Two problems: I haven’t encountered CDATA in my XML yet, but I do hope to develop a better solution than offered here when I do. The other is that SimpleXML chokes on illegal characters, a unfortunately common occurrence in documents coming from III’s XML Server.

tags: cdata, docs, documentation, php, php5, simplexml, xml server, xml

The Zend overview of the new XML features in PHP 5 has re-energized me for building XML Server Applications at my library.

xml, php, web development

Interesting: Cladonia Exchanger XML Editor, a Java-based app that makes reading raw XML easy. Much easier than in a regular text editor, even with syntax highlighting.

tags: cladonia, cladonia exchanger xml editor, exchanger, exchanger xml editor, raw xml, syntax highlighting, text editor, xml, xml editor, xslt debugger, xslt editor

Ryan beat me to reporting on the interesting new services at the Ockham Network (noted in this Web4lib post). The easiest one to grok is this spelling service, but there are others that are cooler.

He also alerted me to a Perl script to proxy Z39.50 to RSS. Though for those more into PHP (like me), I’d like to point out the YAZ extension from the folks at Index Data.

This extension offers a PHP interface to the YAZ toolkit that implements the Z39.50 Protocol for Information Retrieval. With this extension you can easily implement a Z39.50 origin (client) that searches or scans Z39.50 targets (servers) in parallel.

The module hides most of the complexity of Z39.50 so it should be fairly easy to use. It supports persistent stateless connections very similar to those offered by the various RDB APIs that are available for PHP. This means that sessions are stateless but shared among users, thus saving the connect and initialize phase steps in most cases.

Clearly, if I wasn’t so lazy, I’d get around to compiling YAZ into my PHP and actually build something with it. Though without Z39.50 on my own ILS, the incentive is understandably diminished.

Finally, I’ve gotten an answer about indexing cat dates in III so they can be used in searches or sorts. The answer is mostly “no,” but I go into a little more detail at LibDev.

tags: cat date, ils, index data, information retrieval, libaries, library, library catalog, library systems, ockham, opac, perl script, php, rss, search by cat date, sort by cat date, xml, yaz, z39.50, z39.50 proxy

I can’t explain why, at least not yet, but I’m looking for a way to search the iTunes Music Store catalog outside of iTunes. Rumors of an iTunes-Google partnership have been flying lately, but what I really want is a webservice/API I can use. Yes, Apple offers an affiliate program that supports direct links, but again, they don’t offer an Amazon-style API to search their catalog.

All of this has me thinking about reverse-engineering the iTMS to build the webservice I’m looking for. DVD Jon made news not so long ago with PyMusique, now rewritten as SharpMusique, but even before that, Jason Rohrer released iTMS-4-all.

Rohrer’s work is more in line with what I’m trying to do, so I’m exploring that concept a little. iTMS-4-all is a simple web browsing interface to the store. Jean-Yves Stervinou explains:

iTunes 4 is a beautiful example of a “specialized browser”. It uses html to render pages with texts and pictures, but it also uses macosX standard GUI elements when appropriate. When you browse the albums/artists, iTunes in fact gets the contents of these lists from a Web server out there at Apple (phobos is its nickname). The format for these lists is XML [...]. iTunes reads this XML list then uses a standard list browser to show you the content.

Stervinou describes the entire iTunes store as a REST webservice, but one which Apple has chosen to keep private. Rohrer describes the problems of interacting with the ITMS encrypted content. He (and contributors) were successful, but Apple changed the encryption after iTunes 4.7 was released. It didn’t take long for DVD Jon to get around the change, but it (or something else, I haven’t looked yet) has disabled iTMS-4-all. Too bad, too, because there’s a lot we might be able to do with such a webservice. DownhillBattle.org contemplates some of these uses in their iTMS-4-all announcement (Jason Rohrer is somehow involved with Downhill Battle).

More reading: Free Software Magazine did some poking at iTunes, The g4tv Screensavers crew looks into iTunes Hackery, Apple does offer a very limited iTunes RSS feed generator, XMLHead looks at the structure of iTunes affiliate links, and (update) here’s some talk about the iTMS XML interface before they started encrypting it.

tags: itms, itms-4-all, itunes, itunes music store, itunes music store api, music store, music store api, pymuscique, webservice, webservices, xml

I want Wikipedia to have an API, but it doesn’t. Some web searching turned up Gina Trapani’s WikipedizeText, but that still wasn’t exactly what I wanted. A note in the source code, however, put me back on the trail to the Wikipedia database downloads, and while that’s not what I want, I did learn that they’ve got a table of just the article titles (over 1.2 million of them) in their downloads.

Some of this is related to my interest in making Wikipedia work better in an academic library context, but I’ve got other plans too. With luck, we’ll see a beta release this week.

tags: api, application programming interface, article titles, database download, free encyclopedia, hacking, rss, web services, webservices, wikipedia, xml

Flash app dynamically generates charts based on XML formated data or values in a PHP array.

XML/SWF Charts is a simple, yet powerful tool to create attractive web charts and graphs from dynamic XML data. Create an XML source to describe a chart, then pass it to this tool’s flash file to generate the chart. The same tool also accepts PHP sources. XML/SWF Charts makes the best of both the XML and SWF worlds. XML provides flexible data generation, and Flash provides the best graphic quality.

More info here.

tags: chart, charts, dynamic, flash, graph, graphs, php, swf, xml

WordPress’s XML-RPC support looks pretty good. Heck, it supports a half dozen APIs and works well with ecto … except for tag support, which is my only complaint with it so far.

The Movable Type API supports a “keywords” field that I’m thinking can be hijacked as a “tags” field instead, but while ecto sends the goods — I can see them in the XML-RPC data that gets sent out, WordPress seems to ignore them upon receipt. So I’m looking around the Wordpress plugin API docs for a solution, but all I can find is an undocumented mention of xmlrpc_methods in Skippy’s list of plugin hooks.

Technorati Tags: api, codex, ecto, plugin, tag, tags, xml, xml-rpc