You might first want to read Basic Web Scraping: Pulling Out Data From Google Search Results.
In the other Basic Web Scraping post we created a Simple Web Scraper that retrieved Google’s Search Result Pages for some keyword and scraped the “Number of Pages” indexed for the keyword. That was a good starting point in learning web scraping, that’s why in this post we’re going to extend that scraper to return one more information, “Related Keywords”.
Actually, Related Searches is a bunch of keywords that Google displays at the bottom of search result pages. These are not displayed all the keywords that you search for, but only for keywords that are somewhat broad. These “related Searches” are the keywords that Google has evaluated to be related with the one searched for.
To scrape this, we’d first need to analyze the HTML Code of Google Search Result. We need to find out where the Related Searches block is in the code, typically it’d like:
<h2 class=r>Searches related to:<b> computer programming</b></h2><table
border=0 cellpadding=0 cellspacing=0 style="margin-top:6px"><tr
style="font-size:84%"><td style="padding:0 30px 6px 0"
valign=top><a href="/search?hl=en&client=firefox-a&rls=org.mozilla:en-US:official&hs=lS4&q=computer+programming+schools&revid=92395746&sa=X&oi=revisions_inline&resnum=0&ct=broad-revision&cd=1">computer
programming <b>schools</b></a></td><td> </td><td
style="padding:0 30px 6px 0" valign=top><a href="/search?hl=en&client=firefox-a&rls=org.mozilla:en-US:official&hs=lS4&q=computer+programming+careers&revid=92395746&sa=X&oi=revisions_inline&resnum=0&ct=broad-revision&cd=2">computer
programming <b>careers</b></a></td><td> </td><td
style="padding:0 30px 6px 0" valign=top><a href="/search?hl=en&client=firefox-a&rls=org.mozilla:en-US:official&hs=lS4&q=computer+programming+languages&revid=92395746&sa=X&oi=revisions_inline&resnum=0&ct=broad-revision&cd=3">computer
programming <b>languages</b></a></td><td> </td><td
style="padding:0 30px 6px 0" valign=top><a href="/search?hl=en&client=firefox-a&rls=org.mozilla:en-US:official&hs=lS4&q=computer+programming+c%2B%2B&revid=92395746&sa=X&oi=revisions_inline&resnum=0&ct=broad-revision&cd=4">computer
programming <b>c++</b></a></td><td> </td></tr><tr
style="font-size:84%"><td style="padding:0 30px 6px 0"
valign=top><a href="/search?hl=en&client=firefox-a&rls=org.mozilla:en-US:official&hs=lS4&q=computer+programming+information&revid=92395746&sa=X&oi=revisions_inline&resnum=0&ct=broad-revision&cd=5">computer
programming <b>information</b></a></td><td> </td><td
style="padding:0 30px 6px 0" valign=top><a href="/search?hl=en&client=firefox-a&rls=org.mozilla:en-US:official&hs=lS4&q=basic+computer+programming&revid=92395746&sa=X&oi=revisions_inline&resnum=0&ct=broad-revision&cd=6"><b>basic</b>
computer programming</a></td><td> </td><td
style="padding:0 30px 6px 0" valign=top><a href="/search?hl=en&client=firefox-a&rls=org.mozilla:en-US:official&hs=lS4&q=computer+programming+for+dummies&revid=92395746&sa=X&oi=revisions_inline&resnum=0&ct=broad-revision&cd=7">computer
programming <b>for dummies</b></a></td><td> </td><td
style="padding:0 30px 6px 0" valign=top><a href="/search?hl=en&client=firefox-a&rls=org.mozilla:en-US:official&hs=lS4&q=game+programming&revid=92395746&sa=X&oi=revisions_inline&resnum=0&ct=broad-revision&cd=8"><b>game</b>
programming</a></td><td> </td></tr></table>
Remember our goal here is to find out certain footprint or consistent block in the code (which always will be on every page we request), out of which the needed data (Related Searches) can be pulled out.
Here, we can safely assume it to be:
<h2 class=r>Searches related to:
and
</td></tr></table>
So if we do a search for the above block in the code, we can easily pull the required information.
Now, we can follow the following steps to scrape the required information:
- Retrieve the required page.
- Look for the consistent part of code that uniquely encloses or identifies the required information. Scrape that block.
- Pull the required data out.
Following is the code listing:
<html>
<head>
<title>Google Result Scraper</title>
</head>
<body>
<p align="center" style="font-size:500%"><font color="#0000FF">G</font><font color="#FF0000">o</font><font color="#FFFF00">o</font><font color="#0000FF">g</font><font color="#00FF00">l</font><font color="#FF0000">e</font>
<font size="2"><br />Result Scraper</font></p>
<?php
$s=$_GET['s'];
if(isset($s))
{
//*******F I R S T P A R T*********
//Find the number of pages indexed for the searched term
//*From previous part
echo "<p><i>Search for $s</i></p>";
$s=urlencode($s);
$main_data=file_get_contents("http://www.google.com/search?hl=en&q=".$s."&btnG=Google+Search");
//strip off HTML
$data=strip_tags($main_data);
//now $data only has text NO HTML
//these have to ound out in the fetched data
$find='Results 1 - 10 of about ';
$find2=' for';
//have text beginning from $find
$data=strstr($data,$find);
//find position of $find2
//there might be many occurence
//but it'd give position of the first one,
//which is what we want, anyway
$pos=strpos($data,$find2);
//take substring out, which'd be the number we want
$search_number=substr($data,strlen($find), $pos-strlen($find));
echo "Pages Indexed: $search_number";
//********S E C O N D P A R T*******
//Find related searches
echo "<h3>Related Keywords</h3>";
//these have to found out in the fetched data
$find='<h2 class=r>Searches related to:';
$find2='</table>';
$find3='<table border=0';
//have text beginning from $find
$data=strstr($main_data,$find);
//find position of $find2
//there might be many occurence
//but it'd give position of the first one,
//which is what we want, anyway
$pos=strpos($data,$find2);
//take substring out, this is the block of data
//that we'd fetch required information off of.
$related_search_block=substr($data,strlen($find), $pos-strlen($find));
//pull out the required data, stripping off "Searches related to.."
$related_searches=strstr($related_search_block,$find3);
//now we only have the keywords, of course formatted as is
//with tables
//strip off HTML, therefore taking off table and various
//other formattings
$related_searches=strip_tags($related_searches);
//now we have the keywords (plain text) sepearted with
//each other using " '
//explode it
$keywords=explode(' ',$related_searches);
//now we a nice array having all the keywords
//print the keywords
//nicely formatted using <ol> (ordered list)
echo "<ol>";
foreach($keywords as $keyword)
{
if($keyword!='' && $keyword!=' ')
echo "<li>
$keyword
</li>";
}
echo "</ol>";
}
else
{
?>
<form name="form1" id="form1" method="get" action="">
<div align="center">
<p>
<input name="s" type="text" id="s" size="50" />
<input type="submit" name="Submit" value="Find Related Keywords" />
</p>
</div>
</form>
<p> </p>
<p> </p>
<p> </p>
<p> </p>
<p>
<?php
}
?>
</p>
<p align="right"><font size="2">by <a href="http://learning-computer-programming.blogspot.com/">Learning
Computer Programming</a></font></p>
</body>
</html>
Although this script is not very useful as it is (after all it’s meant for learning purpose) you can make it more useful by extending it. one thing that’d be nice is to hav it search for related keywords and again take each keyword as a base for further searches. This way it’d be able to supply you with many keywords related to the one entered. Best thing is, the keywords will be Googly Related!
Previous Posts:
-
Web Scraping: Pulling Out Data From Google Search Results
-
Creating a Simple Form Validation Script Using JavaScript
-
Deigning a Simple HTML Menu-Bar Using CSS
-
Blogger: Method to Add ‘Link to This Post’ Widget on Your Posts
-
New Working Method of Making Blogger Title Tags SEO Friendly
