What is the right way of storing screen-scraping data?

i'm working on a web site. it is scraping product details(names, features, prices etc.) from various web sites, processing and displaying them. i'am considering to run update script on each day and keep data fresh.

    scrape data
    process them
    store on database
    read(from db) and display them

i'am already storing all the data in a sql schema but i'm not sure. After each update, all the old records are vanishing. if the scraped new data comes corrupted somehow, there is nothing to show.

so, is there any common way to archive the old data? which one is more convenient: seperate sql schemas or xml files? or something else?

Source: http://stackoverflow.com/questions/13686474/what-is-the-right-way-of-storing-screen-scraping-data

Scraping dynamic data

I am scraping profiles on ask.fm for a research question. The problem is that only the top most recent questions are viewable and I have to click "view more" to see the next 15.

The source code for clicking view more looks like this:

<input class="submit-button-more submit-button-more-active" name="commit" onclick="return Forms.More.allowSubmit(this)" type="submit" value="View more" />

What is an easy way of calling this 4 times before scraping it. I want the most recent 60 posts on the site. Python is preferable.

You could probably use selenium to browse to the website and click on the button/link a few times. You can get that here:

    https://pypi.python.org/pypi/selenium

Or you might be able to do it with mechanize:

    http://wwwsearch.sourceforge.net/mechanize/

I have also heard good things about twill, but never used it myself:

    http://twill.idyll.org/



Source: http://stackoverflow.com/questions/19437782/scraping-dynamic-data

Web Scraping data from different sites

I am looking for a few ideas on how can I solve a design problem I'm going to be faced with building a web scraper to scrape multiple sites. Writing the scraper(s) is not the problem, matching the data from different sites (which may have small differences) is.

For the sake of being generic assume that I am scraping something like this from two or more different sites:

    public class Data {
        public int id;
        public String firstname;
        public String surname;
        ....
    }

If i scrape this from two different sites, I will encounter the situation where I could have the following:

Site A: id=100, firstname=William, surname=Doe

Site B: id=1974, firstname=Bill, surname=Doe

Essentially, I would like to consider these two sets of data the same (they are the same person but with their name slightly different on each site). I am looking for possible design solutions that can handle this.

The only idea I've come up with is scraping the data from a third location and using it as a reference list. Then when I scrape site A or B I can, over time, build up a list of failures and store them in a list for each scraper so that it can know (if i find id=100 then i know that the firstname will be William etc). I can't help but feel this is a rubbish idea!

If you need any more info, or if you think my description is a bit naff, let me know!

Thanks,

DMcB


Source: http://stackoverflow.com/questions/23970057/web-scraping-data-from-different-sites

Scrape Data Point Using Python

I am looking to scrape a data point using Python off of the url http://www.cavirtex.com/orderbook .

The data point I am looking to scrape is the lowest bid offer, which at the current moment looks like this:

<tr>
 <td><b>Jan. 19, 2014, 2:37 a.m.</b></td>
 <td><b>0.0775/0.1146</b></td>
 <td><b>860.00000</b></td>
 <td><b>66.65 CAD</b></td>
</tr>

The relevant point being the 860.00 . I am looking to build this into a script which can send me an email to alert me of certain price differentials compared to other exchanges.

I'm quite noobie so if in your explanations you could offer your thought process on why you've done certain things it would be very much appreciated.

Thank you in advance!

Edit: This is what I have so far which will return me the name of the title correctly, I'm having trouble grabbing the table data though.

import urllib2, sys
from bs4 import BeautifulSoup

site= "http://cavirtex.com/orderbook"
hdr = {'User-Agent': 'Mozilla/5.0'}
req = urllib2.Request(site,headers=hdr)
page = urllib2.urlopen(req)
soup = BeautifulSoup(page)
print soup.title



Here is the code for scraping the lowest bid from the 'Buying BTC' table:

from selenium import webdriver

fp = webdriver.FirefoxProfile()
browser = webdriver.Firefox(firefox_profile=fp)
browser.get('http://www.cavirtex.com/orderbook')

lowest_bid = float('inf')
elements = browser.find_elements_by_xpath('//div[@id="orderbook_buy"]/table/tbody/tr/td')

for element in elements:
    text = element.get_attribute('innerHTML').strip('<b>|</b>')
    try:
        bid = float(text)
        if lowest_bid > bid:
            lowest_bid = bid
    except:
        pass

browser.quit()
print lowest_bid

In order to install Selenium for Python on your Windows-PC, run from a command line:

pip install selenium (or pip install selenium --upgrade if you already have it).

If you want the 'Selling BTC' table instead, then change "orderbook_buy" to "orderbook_sell".

If you want the 'Last Trades' table instead, then change "orderbook_buy" to "orderbook_trades".

Note:

If you consider performance critical, then you can implement the data-scraping via URL-Connection instead of Selenium, and have your program running much faster. However, your code will probably end up being a lot "messier", due to the tedious XML parsing that you'll be obliged to apply...

Here is the code for sending the previous output in an email from yourself to yourself:

import smtplib,ssl

def SendMail(username,password,contents):
    server = Connect(username)
    try:
        server.login(username,password)
        server.sendmail(username,username,contents)
    except smtplib.SMTPException,error:
        Print(error)
    Disconnect(server)

def Connect(username):
    serverName = username[username.index("@")+1:username.index(".")]
    while True:
        try:
            server = smtplib.SMTP(serverDict[serverName])
        except smtplib.SMTPException,error:
            Print(error)
            continue
        try:
            server.ehlo()
            if server.has_extn("starttls"):
                server.starttls()
                server.ehlo()
        except (smtplib.SMTPException,ssl.SSLError),error:
            Print(error)
            Disconnect(server)
            continue
        break
    return server

def Disconnect(server):
    try:
        server.quit()
    except smtplib.SMTPException,error:
        Print(error)

serverDict = {
    "gmail"  :"smtp.gmail.com",
    "hotmail":"smtp.live.com",
    "yahoo"  :"smtp.mail.yahoo.com"
}

SendMail("your_username@your_provider.com","your_password",str(lowest_bid))

The above code should work if your email provider is either gmail or hotmail or yahoo.

Please note that depending on your firewall configuration, it may ask your permission upon the first time you try it...



Source: http://stackoverflow.com/questions/21217034/scrape-data-point-using-python

Data From Web Scraping Using Node.JS Request Is Different From Data Shown In The Browser

Right now, I am doing some simple web scraping, for example get the current train arrival/departure information for one railway station. Here is the example link, http://www.thetrainline.com/Live/arrivals/chester, from this link you can visit the current arrival trains in the chester station.

I am using the node.js request module to do some simple web scraping,

app.get('/railway/arrival', function (req, res, next) {
    console.log("/railway/arrival/  "+req.query["city"]);
    var city = req.query["city"];
    if(typeof city == undefined || city == undefined) { console.log("if it undefined"); city ="liverpool-james-street";}
    getRailwayArrival(city,
       function(err,data){
           res.send(data);
        }
       );
});

function getRailwayArrival(station,callback){
   request({
    uri: "http://www.thetrainline.com/Live/arrivals/"+station,
   }, function(error, response, body) {
      var $ = cheerio.load(body);

      var a = new Array();
      $(".results-contents li a").each(function() {
        var link = $(this);
        //var href = link.attr("href");
        var due = $(this).find('.due').text().replace(/(\r\n|\n|\r|\t)/gm,"");   
        var destination = $(this).find('.destination').text().replace(/(\r\n|\n|\r|\t)/gm,"");
        var on_time = $(this).find('.on-time-yes .on-time').text().replace(/(\r\n|\n|\r|\t)/gm,"");
        if(on_time == undefined)  var on_time_no = $(this).find('.on-time-no').text().replace(/(\r\n|\n|\r|\t)/gm,"");
        var platform = $(this).find('.platform').text().replace(/(\r\n|\n|\r|\t)/gm,"");

        var obj = new Object();
        obj.due = due;obj.destination = destination; obj.on_time = on_time; obj.platform = platform;
        a.push(obj);
console.log("arrival  ".green+due+"  "+destination+"  "+on_time+"  "+platform+"  "+on_time_no);      
    });
    console.log("get station data  "+a.length +"   "+ $(".updated-time").text());
    callback(null,a);

  });
}

The code works by giving me a list of data, however these data are different from the data seen in the browser, though the data come from the same url. I don't know why it is like that. is it because that their server can distinguish the requests sent from server and browser, that if the request is from server, so they sent me the wrong data. How can I overcome this problem ?

thanks in advance.

2 Answers

They must have stored session per click event. Means if u visit that page first time, it will store session and validate that session for next action you perform. Say, u select some value from drop down list. for that click again new value of session is generated that will load data for ur selected combobox value. then u click on show list then that previous session value is validated and you get accurate data.

Now see, if you not catch that session value programatically and not pass as parameter with that request, you will get default loaded data or not get any thing. So, its chalenging for you to chatch that data.Use firebug for help.

Another issue here could be that the generated content occurs through JavaScript run on your machine. jsdom is a module which will provide such content but is not as lightweight.

Cheerio does not execute these scripts and as a result content may not be visible (as you're experiencing). This is an article I read a while back and caused me to have the same discovery, just open the article and search for "jsdom is more powerful" for a quick answer:

Source:http://stackoverflow.com/questions/15785360/data-from-web-scraping-using-node-js-request-is-different-from-data-shown-in-the?rq=1

How Your Online Information is Stolen - The Art of Web Scraping and Data Harvesting

Web scraping, also known as web/internet harvesting involves the use of a computer program which is able to extract data from another program's display output. The main difference between standard parsing and web scraping is that in it, the output being scraped is meant for display to its human viewers instead of simply input to another program.

Therefore, it isn't generally document or structured for practical parsing. Generally web scraping will require that binary data be ignored - this usually means multimedia data or images - and then formatting the pieces that will confuse the desired goal - the text data. This means that in actually, optical character recognition software is a form of visual web scraper.

Usually a transfer of data occurring between two programs would utilize data structures designed to be processed automatically by computers, saving people from having to do this tedious job themselves. This usually involves formats and protocols with rigid structures that are therefore easy to parse, well documented, compact, and function to minimize duplication and ambiguity. In fact, they are so "computer-based" that they are generally not even readable by humans.

If human readability is desired, then the only automated way to accomplish this kind of a data transfer is by way of web scraping. At first, this was practiced in order to read the text data from the display screen of a computer. It was usually accomplished by reading the memory of the terminal via its auxiliary port, or through a connection between one computer's output port and another computer's input port.

It has therefore become a kind of way to parse the HTML text of web pages. The web scraping program is designed to process the text data that is of interest to the human reader, while identifying and removing any unwanted data, images, and formatting for the web design.

Though web scraping is often done for ethical reasons, it is frequently performed in order to swipe the data of "value" from another person or organization's website in order to apply it to someone else's - or to sabotage the original text altogether. Many efforts are now being put into place by webmasters in order to prevent this form of theft and vandalism.

Source:http://ezinearticles.com/?How-Your-Online-Information-is-Stolen---The-Art-of-Web-Scraping-and-Data-Harvesting&id=923976

Automated SEO Tools Can Keep You Out of the SERPs

Every day, thousands of newcomers enter the world of internet marketing. They join all of the popular forums, follow popular advice, and purchase a bunch of tools to automate the process. While all three of these things are full of potential problems and pitfalls, it is the automated tools that have the potential to cause the greatest harm.

Why do People Buy Automated SEO Tools?

Automated SEO tools make some very grand promises. First, they promise to eliminate all of the hard work and effort that is needed to succeed with making money online. Next, they promise to give you an "edge" over your competitors. Finally, they promise to do it all for less than outsourcing.

But most of these tools don't work properly, meaning that any money you spent is money wasted. If you can't use it, you can't get any sort of return on your investment.

The few that do work properly, though, typically use techniques that are frowned upon by the search engines. They violate the terms of service, as well as commonly accepted web etiquette.

For instance, Scrape Box is a tool that is designed to find blogs on which you can comment and generate back links. It's a valuable tool if you're using it to automate the finding of relevant blogs. After that, though, it can only get you in trouble.

Just like most of these tools, Scrape Box is going to guide you through the process of creating a generic comment template. It will then assist you with "spinning" that comment, so that you can have hundreds (or even thousands) of "unique" versions.

What ends up happening, though, is that you end up with comments that resemble gibberish more than anything else. The tool then pushes these comments to blogs with links back to your website. And that's when everything goes downhill.

Search Engine Algorithms vs Automated SEO Tools

The most recent batch of algorithm updates, like Panda and Penguin, are designed to help Google better identify spam that is used for nothing other than search engine optimization. When you use Scrape Box to build and publish your content, you're spamming the web.

When Google's spiders crawl the content on these blogs and identify them as spam, they'll also note the fact that a link was sent back to your site. If you have too many of these, it will raise a red flag and your site may end up deindexed.

If you're lucky, you won't be penalized that harshly. Instead, all of your links will end up devalued. That isn't much better, though, because then the original cash investment in the tool, as well as all of the time you spent setting everything up, will be for nothing.

All of the popular SEO automation tools focus on spamming the web to build back links. This includes:

    Tools designed to automate blog comments

    Tools designed to automate article directory submissions

    Tools designed to submit your site to social bookmarking directories

    Tools designed to spin your content for uniqueness

The end results are disappointing, at best. You spend money on a tool that pushes out thousands of back links that never really help your SEO campaign. Ultimately, your site develops a back link profile that is so damaged that no amount of hard, legitimate work can ever overcome it.

Slow and Steady Wins the Race

The allure and appeal of these tools is simple to understand. They eliminate all of the hard work that would go into building a real back link profile. The problem, though, is easy to understand.

If you were to perform these tasks manually it would take a long time. But the quality of the back links you receive will far outweigh anything the automated tools could do for you.

Sure, you might not be able to manually generate a thousand back links in one day. But Google knows that, and when you do so you immediately set off a red flag. That's not how you build a solid, long lasting ranking.

By handling each step in your SEO campaign manually you will build a more natural and diverse back link footprint over time. Your rankings won't come quickly, but they'll stick for a very long time.

Source:http://ezinearticles.com/?Automated-SEO-Tools-Can-Keep-You-Out-of-the-SERPs&id=7427357