Sunday, 30 November 2014

The Roots of Web Scraping and the Wisdom behind It

You may be wondering how data mining came into existence. This effective and innovative trend in business and research is indeed something commendable and the genius behind it is worth great reward. To have a clear view of the origin of web scraping, the following important factors that contribute to the creation of this phenomenon called data collection or web scraping are considered.

Foundations

Unlike any other innovation, no specific date can be clearly pointed out as the birthdate of data mining. It has come into existence as a result of several problem solving processes in major data gathering and handling situations. It appears that cyber technology has opened a Pandora box of “anything can happen” experiences. Moreover, the shift from physical to virtual data collection has resulted in a bulk of database that needed to be organized, analyzed and utilized.

Source: http://www.loginworks.com/blogs/web-scraping-blogs/roots-web-scraping-wisdom-behind/

Wednesday, 26 November 2014

Web Scraping Tools for Non-developers

I recently spoke with a resource-limited organization that is investigating government corruption and wants to access various public datasets to monitor politicians and law firms. They don’t have developers in-house, but feel pretty comfortable analyzing datasets in CSV form. While many public datasources are available in structured form, some sources are hidden in what us data folks call the deep web. Amazon is a nice example of a deep website, where you have to enter text into a search box, click on a few buttons to narrow down your results, and finally access relatively structured data (prices, model numbers, etc.) embedded in HTML. Amazon has a structured database of their products somewhere, but all you get to see is a bunch of webpages trapped behind some forms.

A developer usually isn’t hindered by the deep web. If we want the data on a webpage, we can automate form submissions and key presses, and we can parse some ugly HTML before emitting reasonably structured CSVs or JSON. But what can one accomplish without writing code?

This turns out to be a hard problem. Lots of companies have tried, to varying degrees of success, to build a programmer-free interface for structured web data extraction. I had the pleasure of working on one such project, called Needlebase at ITA before Google acquired it and closed things down. David Huynh, my wonderful colleague from grad school, prototyped a tool called Sifter that did most of what one would need, but like all good research from 2006, the lasting impact is his paper rather than his software artifact.

Below, I’ve compiled a list of some available tools. The list comes from memory, the advice of some friends that have done this before, and, most productively, a question on Twitter that Hilary Mason was nice enough to retweet.

The bad news is that none of the tools I tested would work out of the box for the specific use case I was testing. To understand why, I’ll break down the steps required for a working web scraper, and then use those steps to explain where various solutions broke down.

The anatomy of a web scraper

There are three steps to a structured extraction pipeline:

    Authenticate yourself. This might require logging in to a website or filling out a CAPTCHA to prove you’re not…a web scraper. Because the source I wanted to scrape required filling out a CAPTCHA, all of the automated tools I’ll review below failed step 1. It suggests that as a low bar, good scrapers should facilitate a human in the loop: automate the things machines are good at automating, and fall back to a human to perform authentication tasks the machines can’t do on their own.

    Navigate to the pages with the data. This might require entering some text into a search box (e.g., searching for a product on Amazon), or it might require clicking “next” through all of the pages that results are split over (often called pagination). Some of the tools I looked at allowed entering text into search boxes, but none of them correctly handled pagination across multiple pages of results.

    Extract the data. On any page you’d like to extract content from, the scraper has to help you identify the data you’d like to extract. The cleanest example of this that I’ve seen is captured in a video for one of the tools below: the interface lets you click on some text you want to pluck out of a website, asks you to label it, and then allows you to correct mistakes it learns how to extract the other examples on the page.

As you’ll see in a moment, the steps at the top of this list are hardest to automate.

What are the tools?

Here are some of the tools that came highly recommended, and my experience with them. None of those passed the CAPTCHA test, so I’ll focus on their handling of navigation and extraction.

    Web Scraper is a Chrome plugin that allows you to build navigable site maps and extract elements from those site maps. It would have done everything necessary in this scenario, except the source I was trying to scrape captured click events on links (I KNOW!), which tripped things up. You should give it a shot if you’d like to scrape a simpler site, and the youtube video that comes with it helps get around the slightly confusing user interface.

    import.io looks like a clean webpage-to-api story. The service views any webpage as a potential data source to generate an API from. If the page you’re looking at has been scraped before, you can access an API or download some of its data. If the page hasn’t been processed before, import.io walks you through the process of building connectors (for navigation) or extractors (to pull out the data) for the site. Once at the page with the data you want, you can annotate a screenshot of the page with the fields you’d like to extract. After you submit your request, it appears to get queued for extraction. I’m still waiting for the data 24 hours after submitting a request, so I can’t vouch for the quality, but the delay suggests that import.io uses crowd workers to turn your instructions into some sort of semi-automated extraction process, which likely helps improve extraction quality. The site I tried to scrape requires an arcane combination of javascript/POST requests that threw import.io’s connectors for a lo
op, and ultimately made it impossible to tell import.io how to navigate the site. Despite the complications, import.io seems like one of the more polished website-to-data efforts on this list.

    Kimono was one of the most popular suggestions I got, and is quite polished. After installing the Kimono bookmarklet in your browser, you can select elements of the page you wish to extract, and provide some positive/negative examples to train the extractor. This means that unlike import.io, you don’t have to wait to get access to the extracted data. After labeling the data, you can quickly export it as CSV/JSON/a web endpoint. The tool worked seamlessly to extract a feed from the Hackernews front page, but I’d imagine that failures in the automated approach would make me wish I had access to import.io’s crowd workers. The tool would be high on my list except that navigation/pagination is coming soon, and will ultimately cost money.

    Dapper, which is now owned by Yahoo!, provides about the same level of scraping capabilities as Kimono. You can extract content, but like Kimono it’s unclear how to navigate/paginate.

    Google Docs was an unexpected contender. If the data you’re extracting is in an HTML table/RSS Feed/CSV file/XML document on a single webpage with no navigation/authentication, you can use one of the Import* functions in Google Docs. The IMPORTHTML macro worked as advertised in a quick test.

    iMacros is a tool that I could imagine solves all of the tasks I wanted, but costs more than I was willing to pay to write this blog post. Interestingly, the free version handles the steps that the other tools on this list don’t do as well: navigation. Through your browser, iMacros lets you automate filling out forms, clicking on “next” links, etc. To perform extraction, you have to pay at least $495.

    A friend has used Screen-scraper in the past with good outcomes. It handles navigation as well as extraction, but costs money and requires a small amount of programming/tokenization skills.

    Winautomation seems cool, but it’s only available for Windows, which was a dead end for me.

So that’s it? Nothing works?

Not quite. None of these tools solved the problem I had on a very challenging website: the site clearly didn’t want to be crawled given the CAPTCHA, and the javascript-submitted POST requests threw most of the tools that expected navigation through links for a loop. Still, most of the tools I reviewed have snazzy demos, and I was able to use some of them for extracting content from sites that were less challenging than the one I initially intended to scrape.

All hope is not lost, however. Where pure automation fails, a human can step in. Several proposals suggested paying people on oDesk, Mechanical Turk, or CrowdFlower to extract the content with a human touch. This would certainly get us past the CAPTCHA and hard-to-automate navigation. It might get pretty expensive to have humans copy/paste the data for extraction, however. Given that the tools above are good at extracting content from any single page, I suspect there’s room for a human-in-the-loop scraping tool to steal the show: humans can navigate and train the extraction step, and the machine can perform the extraction. I suspect that’s what import.io is up to, and I’m hopeful they keep the tool available to folks like the ones I initially tried to help.

While we’re on the topic of human-powered solutions, it might make sense to hire a developer on oDesk to just implement the scraper for the site this organization was looking at. While a lot of the developer-free tools I mentioned above look promising, there are clearly cases where paying someone for a few hours of script-building just makes sense.

Source: http://blog.marcua.net/post/74655674340

Sunday, 23 November 2014

Using Kimono Labs to Scrape the Web for Free

Historically, I have written and presented about big data—using data to create insights, and how to automate your data ingestion process by connecting to APIs and leveraging advanced database technologies.

Recently I spoke at SMX West about leveraging the rich data in webmaster tools. After the panel, I was approached by the in-house SEO of a small company, who asked me how he could extract and leverage all the rich data out there without having a development team or large budget. I pointed him to the CSV exports and some of the more hidden tools to extract Google data, such as the GA Query Builder and the YouTube Analytics Query Builder.

However, what do you do if there is no API? What do you do if you want to look at unstructured data, or use a data source that does not provide an export?

For today's analytics pros, the world of scraping—or content extraction (sounds less black hat)—has evolved a lot, and there are lots of great technologies and tools out there to help solve those problems. To do so, many companies have emerged that specialize in programmatic content extraction such as Mozenda, ScraperWiki, ImprtIO, and Outwit, but for today's example I will use Kimono Labs. Kimono is simple and easy to use and offers very competitive pricing (including a very functional free version). I should also note that I have no connection to Kimono; it's simply the tool I used for this example.

Before we get into the actual "scraping" I want to briefly discuss how these tools work.

The purpose of a tool like Kimono is to take unstructured data (not organized or exportable) and convert it into a structured format. The prime example of this is any ranking tool. A ranking tool reads Google's results page, extracts the information and, based on certain rules, it creates a visual view of the data which is your ranking report.

Kimono Labs allows you to extract this data either on demand or as a scheduled job. Once you've extracted the data, it then allows you to either download it via a file or extract it via their own API. This is where Kimono really shines—it basically allows you to take any website or data source and turn it into an API or automated export.

For today's exercise I would like to create two scrapers.

A. A ranking tool that will take Google's results and store them in a data set, just like any other ranking tool. (Disclaimer: this is meant only as an example, as scraping Google's results is against Google's Terms of Service).

B. A ranking tool for Slideshare. We will simulate a Slideshare search and then extract all the results including some additional metrics. Once we have collected this data, we will look at the types of insights you are able to generate.

1. Sign up

Signup is simple; just go to http://www.kimonolabs.com/signup and complete the form. You will then be brought to a welcome page where you will be asked to drag their bookmarklet into your bookmarks bar.

The Kimonify Bookmarklet is the trigger that will start the application.

2. Building a ranking tool

Simply navigate your browser to Google and perform a search; in this example I am going to use the term "scraping." Once the results pages are displayed, press the kimonify button (in some cases you might need to search again). Once you complete your search you should see a screen like the one below:

It is basically the default results page, but on the top you should see the Kimono Tool Bar. Let's have a close look at that:

The bar is broken down into a few actions:

    URL – Is the current URL you are analyzing.

    ITEM NAME – Once you define an item to collect, you should name it.

    ITEM COUNT – This will show you the number of results in your current collection.

    NEW ITEM – Once you have completed the first item, you can click this to start to collect the next set.

    PAGINATION – You use this mode to define the pagination link.

    UNDO – I hope I don't have to explain this ;)

    EXTRACTOR VIEW – The mode you see in the screenshot above.

    MODEL VIEW – Shows you the data model (the items and the type).

    DATA VIEW – Shows you the actual data the current page would collect.

    DONE – Saves your newly created API.

After you press the bookmarklet you need to start tagging the individual elements you want to extract. You can do this simply by clicking on the desired elements on the page (if you hover over it, it changes color for collectable elements).

Kimono will then try to identify similar elements on the page; it will highlight some suggested ones and you can confirm a suggestion via the little checkmark:

A great way to make sure you have the correct elements is by looking at the count. For example, we know that Google shows 10 results per page, therefore we want to see "10" in the item count box, which indicates that we have 10 similar items marked. Now go ahead and name your new item group. Each collection of elements should have a unique name. In this page, it would be "Title".

Now it's time to confirm the data; just click on the little Data icon to see a preview of the actual data this page would collect. In the data view you can switch between different formats (JSON, CSV and RSS). If everything went well, it should look like this:

As you can see, it not only extracted the visual title but also the underlying link. Good job!

To collect some more info, click on the Extractor icon again and pick out the next element.

Now click on the Plus icon and then on the description of the first listing. Since the first listing contains site links, it is not clear to Kimono what the structure is, so we need to help it along and click on the next description as well.

As soon as you do this, Kimono will identify some other descriptions; however, our count only shows 8 instead of the 10 items that are actually on that page. As we scroll down, we see some entries with author markup; Kimono is not sure if they are part of the set, so click the little checkbox to confirm. Your count should jump to 10.

Now that you identified all 10 objects, go ahead and name that group; the process is the same as in the Title example. In order to make our Tool better than others, I would like to add one more set— the author info.

Once again, click the Plus icon to start a new collection and scroll down to click on the author name. Because this is totally unstructured, Google will make a few recommendations; in this case, we are working on the exclusion process, so press the X for everything that's not an author name. Since the word "by" is included, highlight only the name and not "by" to exclude that (keep in mind you can always undo if things get odd).

Once you've highlighted both names, results should look like the one below, with the count in the circle being 2 representing the two authors listed on this page.

Out of interest I did the same for the number of people in their Google+ circles. Once you have done that, click on the Model View button, and you should see all the fields. If you click on the Data View you should see the data set with the authors and circles.

As a final step, let's go back to the Extractor view and define the pagination; just click the Pagination button (it looks like a book) and select the next link. Once you have done that, click Done.

You will be presented with a screen similar to this one:

Here you simply name your API, define how often you want this data to be extracted and how many pages you want to crawl. All of these settings can be changed manually; I would leave it with On demand and 10 pages max to not overuse your credits.

Once you've saved your API, there are a ton of options (too many to review here). Kimono has a great learning section you can check out any time.

To collect the listings requires a quick setup. Click on the pagination tab, turn it on and set your schedule to On demand to pull data when you ask it to. Your screen should look like this:

Now press Crawl and Kimono will start collecting your data. If you see any issues, you can always click on Edit API and go back to the extraction screen.

Once the crawl is completed, go to the Test Endpoint tab to view or download your data (I prefer CSV because you can easily open it in Excel, CSV, Spotfire, etc.) A possible next step here would be doing this for multiple keywords and then analyzing the impact of, say, G+ Authority on rankings. Again, many of you might say that a ranking tool can already do this, and that's true, but I wanted to cover the basics before we dive into the next one.

3. Extracting SlideShare data

With Slideshare's recent growth in popularity it has become a document sharing tool of choice for many marketers. But what's really on Slideshare, who are the influencers, what makes it tick? We can utilize a custom scraper to extract that kind data from Slideshare.

To get started, point your browser to Slideshare and pick a keyword to search for.

For our example I want to look at presentations that talk about PPC in English, sorted by popularity, so the URL would be:

http://www.slideshare.net/search/slideshow?ft=presentations&lang=en&page=1&q=ppc&qf=qf1&sort=views&ud=any

Once you are on that page, pick the Kimonify button as you did earlier and tag the elements. In this case I will tag:

    Title
    Description
    Category
    Author
    Likes
    Slides

Once you have tagged those, go ahead and add the pagination as described above.

That will make a nice rich dataset which should look like this:

Hit Done and you're finished. In order to quickly highlight the benefits of this rich data, I am going to load the data into Spotfire to get some interesting statics (I hope).

4. Insights

Rather than do a step-by-step walktrough of how to build dashboards, which you can find here, I just want to show you some insights you can glean from this data:

    Most Popular Authors by Category. This shows you the top contributors and the categories they are in for PPC (squares sized by Likes)

    Correlations. Is there a correlation between the numbers of slides vs. the number of likes? Why not find out?
    Category with the most PPC content. Discover where your content works best (most likes).

5. Output

One of the great things about Kimono we have not really covered is that it actually converts websites into APIs. That means you build them once, and each time you need the data you can call it up. As an example, if I call up the Slideshare API again tomorrow, the data will be different. So you basically appified Slisdeshare. The interesting part here is the flexibility that Kimono offers. If you go to the How to Use slide, you will see the way Kimono treats the Source URL In this case it looks like this:

The way you can pull data from Kimono aside from the export is their own API; in this case you call the default URL,

http://www.kimonolabs.com/api/YOURPAIID?apikey=YO...

You would get the default data from the original URL; however, as illustrated in the table above, you can dynamically adjust elements of the source URL.

For example, if you append "&q=SEO"

(http://www.kimonolabs.com/api/YOURPAIID?apikey=YOURAPIKEY&q=SEO)

you would get the top slides for SEO instead of PPC. You can change any of the URL options easily.

I know this was a lot of information, but believe me when I tell you, we just scratched the surface. Tools like Kimono offer a variety of advanced functions that really open up the possibilities. Once you start to realize the potential, you will come up with some amazing, innovative ideas. I would love to see some of them here shared in the comments. So get out there and start scraping … and please feel free to tweet at me or reply below with any questions or comments!

Source: http://moz.com/blog/web-scraping-with-kimono-labs

Thursday, 13 November 2014

Future of Web Scraping

The Internet is large, complex and ever-evolving. Nearly 90% of all the data in the world has been generated over the last two years. In this vast ocean of data, how does one get to the relevant piece of information? This is where web scraping takes over.

Web scrapers attach themselves, like a leech, to this beast and ride the waves by extracting information form websites at will. Granted “scraping” doesn’t have a lot of positive connotations, yet it happens to be the only way to access data or content from a web site without RSS or an open API.

Future of Web Scraping

Web scraping faces testing times ahead. We outline why there may be some serious challenges to its future.

With rise in data, redundancies in web scraping are rising. No more is web scraping a domain of the coders; in fact, companies now offer customized scraping tools to clients which they can use to get the data they want. The outcome of everyone equipped to crawl, scrape, and extract, is unnecessary waste of precious man-power. Collaborative scraping could well heal this hurt. Here, where one web crawler does a broad scraping, the others scrape data off an API. An extension of the problem is that text retrieval attracts more attention than multimedia; and with websites becoming more complex, this enforces limited scraping capacity.

Easily, the biggest challenge to web scraping technology is Privacy concerns. With data freely available (most of it voluntary, much of it involuntary), the call for stricter legislation rings loudest. Unintended users can easily target a company and take advantage of the business using web scraping. The disdain with which “do not scrape” policies are treated and terms of usage violated, tells us that even legal restrictions are not enough. This begs to ask an age-old question: is scraping legal?

Is Crawling Legal? from PromptCloud

The flipside to this argument is that if technological barriers replace legal clauses, then web scraping will see a steady, and sure, decline. This is a distinct possibility since the only way scraping activity thrives is on the grid, and if the very means are taken away and programs no longer have access to website information, then web scraping by itself will be wiped out.

Building the Future

On the same thought is the growing trend of accepting “open data”. The open data policy, while long mused hasn’t been used at the scale it should be. The old way was to believe that closed data is the edge over competitors. But that mindset is changing. Increasingly, websites are beginning to offer APIs and embracing open data. But what’s the advantage of doing so?

Selling APIs not only brings in the money, but also is useful in driving back traffic to the sites! APIs are also a more controlled, cleaner way of turning sites into services. Steadily many successful sites like Twitter, LinkedIn etc. are offering access to their APIs with paid services and actively blocking scraper and bots.

Yet, beyond these obvious challenges, there’s a glimmer of hope for web scraping. And this is based on a singular factor: the growing need for data!

With Internet & web technology spreading, massive amounts of data will be accessible on the web. Particularly with increased adoption of mobile internet. According to one report, by 2020, the number of mobile internet users will hit 3.8 billion, or around half of the world’s population!

Since ‘big data’ can be both, structured & unstructured; web scraping tools will only get sharper and incisive. There is fierce competition between those who provide web scraping solutions. With the rise of open source languages like Python, R & Ruby, Customized scraping tools will only flourish bringing in a new wave of data collection and aggregation methods.

Source: https://www.promptcloud.com/blog/Future-of-Web-Scraping

Wednesday, 12 November 2014

3 Reasons to Up Your Web Scraping Game

If you aren’t using a machine-learning-driven intelligent Web scraping solution yet, here are three reasons why you might want to abandon that entry-level Web-scraping software or cut your high-cost script-writing approach.

    You need to keep an eye on a large number of web sources that get updated frequently.
    Understanding what’s changed is at least as critical as the data itself.
    You don’t want maintenance and scheduling to drag you down.

Here’s what an intelligent Web-scraping solution can deliver – and why:

1. Better data monitoring of an ever-shifting Web

If you need to keep a watch over hundreds, thousands or even tens of thousands of sites, an intelligent Web scraper is a must, because:

    It can scale – easily adding new websites, coordinating extraction routines, and automating the normalization of data across different websites.

    It can navigate and extract data from websites efficiently. Script-based approaches typically only can view a Web page in isolation, making it difficult to optimize navigation across unique pages of a targeted site. More intelligent approaches can be trained to bypass unnecessary links and leave a lighter footprint on the sites you need to access. And, they can monitor millions of precise Web data points quickly. This means you can monitor more pages on more sites with more frequent updates.

2. Critical alerts to Web data changes

A key sales executive suddenly drops off of the management page of your main competitor. That can mean big shakeup in the entire organization, which your sales team can jump on.

An intelligent Web scraper can alert you to this personnel shift because it can be set to monitor for just the changes; less powerful technologies or script-based approaches can’t. Whether you’re tracking price shifts, people moves, or product changes (or more) intelligent Web scraping delivers more profound insights.

3. Maintenance may become your biggest nightmare

You’ve purchased an entry-level tool and built out scrapers for a few hundred sites.  At first, everything seems fine. But, within weeks you begin to notice that your data is incomplete and not being updated as you’d expected. Why did your data deliveries disappear?

Reality is that these low-cost tools are simply not designed for mission-critical business applications – on the surface they look helpful and easy to use, but underneath the surface they are script-based and highly dependent upon the HTML of a website. But websites change, and entry-level web scraping tools are simply not engineered to adapt to those changes.

And, most of these tools are simply not designed for enterprise use. They have limited reporting, if any, so the only way to know whether they’re successfully completing their tasks is by finding gaps in the data – often when it’s too late.

An intelligent web scraping approach doesn’t rely upon the HTML of a web page. It uses machine learning algorithms which view the web the same way a user might. A typical reader doesn’t get confused when a font or color is changed on a website, and neither do these algorithms. But simple approaches to web scraping are highly dependent on the specific HTML to help it understand the content of a page. So, when websites have design changes (on average once every 18 months), the software fails.

While entry-level web scraping software can be an easy solution for simple, one-time web scraping projects, the scripts they generate are fragile and the resources required for tracking and maintenance can become overwhelming when you need to regularly extract data from multiple sites.

Case in point: Shopzilla assimilates data five times faster than outsourced Web scrapers

To demonstrate the power of intelligent Web scraping, here’s a real-life example from Shopzilla.  Shopzilla manages a premier portfolio of online shopping brands in the United States and Europe, connecting more than 40 million shoppers each month with millions of products from retailers worldwide. With the explosive growth of retail data on the Web, Shopzilla’s outsourced, custom-built approach, based on scripting, could not add the product lines of new retailers to its site in a timely fashion. It was taking up to two weeks to write the scripts needed to make a single site accessible.

By deploying Connotate’s intelligent web scraping platform on site, Shopzilla gained the ability to harness Web data’s rapid growth and keep up to date. Today, new sources are added in days, not weeks.  The platform continually monitors Web content from thousands of sites, delivering high volumes of data every day in a structured format. The result: 500 percent more data from new retailers. An added bonus: the company has reduced IT maintenance costs and its dependence on outsourced development timetables. Case in point: Deep competitor intelligence in two languages

A global manufacturer needed to monitor competitors’ technology improvements in a field where market leadership hinges on an ability to quickly leverage these advances. That meant accessing scholarly journals and niche sites in multiple languages. Using the Connotate solution, it was able to access highly-targeted, keyword-driven university and industry research journals and blogs in German and English that are hard to reach because they do not support RSS feeds. Our solution also incorporated semantic analysis to tag and categorize data and help identify new technologies and products not currently in the keyword list. The firm enhanced its competitive edge with the up-to-the-minute, precise data it needed.

Is your Web scraping intelligent enough?

See what intelligent agents through an automated Web data extraction and monitoring solution can bring to your business. Contact us and speak with one of experts.

Source:http://www.connotate.com/3-reasons-web-scraping-game-6579#.VGMjH2f4EuQ

Wednesday, 5 November 2014

Web Scraping Popularity Soars

The world is stirred because of the ever-growing web scraping success in almost all of its services. Success stories pertaining to the benefits of online data collection in business, research, politics, health, and almost all aspects of human life are endless. With this popularity surge, it has become a hot issue and many are questioning its legality and reliability.

Looking back, this simple harvesting of pertinent data from competitors and the global market in general like anything else started as a non-threatening and advanced form of web research. Eventually, when the benefits begin to manifest and the system improves, many are lured into it that it has become one of the strongest and fastest growing business in the world.

Simple Beginnings

As naturally as a law of life that great things come from small beginnings, data mining was conceived as a process in gaining information, mostly in research. This act of collecting information through the internet was never imagined to be what it has become nowadays.

Source:http://www.loginworks.com/blogs/web-scraping-blogs/web-scraping-popularity-soars/