Dapper: The Quest To Unlock Web Data (Legally)

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Dapper: The Quest To Unlock Web Data (Legally)
By Alex Iskoldon Analysis
 
We have recently written here about the ongoing transformation of Web Sites into Web Services. In that post we noted that with the rise of APIs, scraping technologies and RSS, web sites are really turning into data services and collectively the web is becoming one gargantuan database. As such, the web is quickly becoming a platform or foundation that powers new kinds of applications that remix information in ways not possible before. The web is also becoming much more connected, not not just on the level of links - but at a much more fundamental, semantic level.
The big picture is always exciting and important, but the mechanics matter too. How exactly do we unlock and correlate information from separate web sites? Ideally, we‘d like for all web sites to offer simple and elegant APIs - like Amazon, del.icio.us and Flickr do today. Alas, this is not feasible today and it isn‘t clear that something like this can be done quickly at all,  on a Web scale. So in the meantime, solutions likeDapper that help you process unstructured information from HTML, clean it, transform it and re-emit as structured XML - these types of solutions are worth serious consideration. So in this post we take a close look at all aspects of Dapper: how it works, what can be done with it, the company‘s business model and legal implications of this service.
How Dapper Works
Dapper offers a way of turning any Web Site into a special kind of Web Service - a Data Service. The difference between a general Web Service and a Data Service is that the latter offers passive, read-only access to information. The former (general web service) may also offer ways to manipulate and change the underlying information. Nevertheless, Data Services are powerful because they unleash information that otherwise would not be accessible. Here‘s an illustration of this in Dapper:

The idea behind Dapper is to create an automatic, visual way of extracting information from HTML pages. It works by taking a few sample pages as input and then letting users visually specify the information that should be extracted. Each page is treated like a record in a database. For example, consider the transformation of a movie page from IMDB:

Dapper runs a quick similarity analysis between sample pages. Even though the analysis is very quick, there is a non-trivial tree-matching algorithm - fine-tuned for HTML - that powers this aspect of Dapper. After analyzing the pages, Dapper presents the user with a highlighter tool for selecting attributes of a record. For example, below you can see how to select a title, highlight a row with title and year, and then chop off pieces using parenthesis.

Testing out Dapper
The Dapper team has worked hard to make text selection easy, but its interface is still somewhat confusing. Particularly, the top controls that allow refinement of a selection needs more work. Right now these controls allow the user to control the similarity matching algorithm. Since the user only has a vague idea of what this is, this control is not terribly useful. In any case, presenting this control using a pulldown with text - instead of a heatmap - would probably be more clear. The other controls are also unclear; and since there are no instructions, the only way to figure it out is by trial and error.
Still, a technical person can use Dapper fairly efficiently. Once you isolate the information that you want to be captured by a single attribute, you can then name the attribute and then move onto the next one. When you are done, the next step is to review and group the content (if you wish). You can then save this application and start using it in variety of ways.

Dapper Applications
So how can this be used? The first use is straightforward - you can use a "Dapp" to process a different URL. For example: if instead of Babel, you pass the IMDBlink to Departed, you will get back the information for that movie instead. So this Dapp can be used to turn any IMDB page into a movie record.
You can also output results into many other formats. Among them you can get results in RSS, Email and HTML output - which to me do not seem as useful for a single record, but become much more interesting when you are looking at a set of records. For example, using the above Dapp and a bit of PHP, you can build an application that generates a formatted RSS feed of new movies shown on the IMDB home page. In addition to the movie title, the feed would include information about release year, director, stars and keywords.

You can also imagine applications that combine different Dapps together. For example, movie information from IMDB can be combined with movie information from Netflix to deliver extended information of a film. Going back to our discussion of theWeb as a Database, this is essentially like doing a join between two tables.
The problem that these applications will face is identity. How can you know that two movies - one at IMDB.com and another one at Netflix - are actually the same movie? There are various ways of determining this, but all boil down to establishing an identifier for a movie that is different from the URL. For example, the combination of a title and director would be a good candidate for such a unique identifier.
So in a nutshell, once the information is extracted, it can be remixed and presented in many new ways. Freed from HTML presentation, raw information from a web page is basically the same database record. And we know how powerful relational databases are - for the past twenty years they have been the backbone of enterprise IT.
Business and Legal questions
Clearly what Dapper is powering is interesting and useful technically. But the business and legal questions are pressing. Is this monetizable? And more importantly: is this even legal? Content scraping is a shady area. Some people claim that it is flat-out illegal. Others say that it is fine, because the content is out there anyway. My take is that it all depends on how the content is used. If the content is scraped and then reused without attribution to the original content provider, that is a straight copyright violation. If on the other hand, the attribution is preserved and the content is remixed in creative ways that still drive traffic to the original source - then it is probably fine. In any case, this is an area without much legal infrastructure - so all players need to be careful.

Now Dapper‘s approach to the problem is entirely different - the company is attempting to both monetize and legalize scraping by acting as a marketplace that connects content owners with companies that want to remix the content. This is both ambitious and a clever play that might just work. The owners of the content often do not have the technical resources and business channels to sell their content. They are not against it in principle, they just do not have the means to do it. On the other hand, the companies that want to leverage existing content are weary of scraping - it just seems like the wrong way of doing it. No one would question calling an Amazon API, but parsing the data out of HTML just does not sound clean.
So Dapper‘s answer seems to be spot on - connect the content owners with content consumers. In the process, establish rules for content distribution, track how it‘s used and help content owners monetize the content. And yes, of course - as with any good pipe - take a cut in each transaction. So while technical purists would argue that the whole notion of scraping is a hack, business people and pragmatists would recognize that Dapper‘s approach to the problem has all the ingredients - that might just make it a successful solution to a real problem.
Conclusion
Will Dapper succeed? It is not obvious and perhaps too early to say. There are a few things that are playing against it. Firstly, ease of use - which the company is rapidly solving. This is something that they control directly and should be able to fix. The second problem is competition. Yahoo! Pipes, Teqlo and Kapow are close enough to be a threat and to cause confusion in the market. But beyond that, is what Dapper is trying to do a good idea? It seems to me that the answer is resounding yes.
Clearly Dapper is not an ideal scenario for exposing the world‘s information. But it is a top-down, unintrusive and perhaps the fastest way of turning any web site into a data service. As such, its power and potential exceeds its drawbacks. We will see what happens and in the mean time, let us know what you think about the technical, business and legal aspects of this fascinating company.