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+For [$work](http://rtgi.fr) I need to write scrapers. It used to be boring and painful. But thanks to [miyagawa](http://search.cpan.org/~miyagawa/), this is not true anymore. [Web::Scraper](http://search.cpan.org/perldoc?Web::Scraper) offer a nice API: you can write your rules using XPath, you can chaine rules, a nice and simple syntax, etc.
+
+I wanted to export my data from my last.fm account but there is no API for this, so I would need to scrap them. All the data are available [as a web page](http://www.last.fm/user/franckcuny/tracks) that list your music. So the scraper need to find how many pages, and find the content on each page to extract a list of your listening.
+
+For the total of pages, it's easy. Let's take a look at the HTML code and search for something like this:
+
+``` html
+    <a class="lastpage" href="/user/franckcuny/tracks?page=272">272</a>
+```
+
+the information is in a class **lastpage**.
+
+Now we need to find our data: I need the artist name, the song name and the date I played this song.
+
+All this data are in a **table**, and each new entry is in a **td**.
+
+``` html
+    <tr id="r9_1580_1920248170" class="odd">
+    [...]
+        <td class="subjectCell">
+        <a href="/music/Earth">Earth</a>
+        <a href="/music/Earth/_/Sonar+and+Depth+Charge">Sonar and Depth Charge</a>
+        </td>
+    [...]
+    <td class="dateCell last">
+        <abbr title="2009-05-13T15:18:25Z">13 May 3:18pm</abbr>
+    </td>
+```
+
+It's simple: information about a song are stored in **subjectcell**, and the artist and song title are each in a tag **a**. The date is in a **dateCell**, and we need the **title** from the **abbr** tag.
+
+The scraper we need to write is
+
+``` perl
+my $scrap = scraper {
+    process 'a[class="lastpage"]', 'last'    => 'TEXT';
+    process 'tr',                  'songs[]' => scraper {
+        process 'abbr',                    'date' => '@title';
+        process 'td[class="subjectCell"]', 'song' => scraper {
+            process 'a', 'info[]' => 'TEXT';
+        };
+    }
+};
+```
+
+The first rule extract the total of page. The second iter on each **tr** and store the content in an array named **songs**. This **tr** need to be scraped. So we look the the **abbr** tag, and store in **date** the property **title**. Then we look for the song and artitst information. We look for the **td** with a class named **subjectCell**, a extract all links.
+
+Our final script will look like this:
+
+``` perl
+ #!/usr/bin/perl -w
+ use strict;
+ use feature ':5.10';
+
+ use Web::Scraper;
+ use URI;
+ use IO::All -utf8;
+
+ my $username = shift;
+ my $output   = shift;
+
+ my $scrap = scraper {
+     process 'a[class="lastpage"]', 'last'    => 'TEXT';
+     process 'tr',                  'songs[]' => scraper {
+         process 'abbr',                    'date' => '@title';
+         process 'td[class="subjectCell"]', 'song' => scraper {
+             process 'a', 'info[]' => 'TEXT';
+         };
+     }
+ };
+
+ my $url = "http://www.last.fm/user/" . $username . "/tracks?page=";
+ scrap_lastfm(1);
+
+ sub scrap_lastfm {
+     my $page      = shift;
+     my $scrap_uri = $url . $page;
+     say $scrap_uri;
+     my $res      = $scrap->scrape(URI->new($scrap_uri));
+     my $lastpage = $res->{last};
+     foreach my $record (@{$res->{songs}}) {
+         my $line = join("\t", @{$record->{song}->{info}}, $record->{date});
+         $line . "\n" >> io $output;
+     }
+     $page++;
+     scrap_lastfm($page) if $page <= $lastpage;
+}
+```
+
+You can use this script like this:
+
+``` bash
+perl lastfmscraper.pl franckcuny store_data.txt
+```