NAME

Parse::MediaWikiDump::Pages - Object capable of processing dump files with a single revision per article

ABOUT

This object is used to access the metadata associated with a MediaWiki instance and provide an iterative interface for extracting the individual articles out of the same. This module does not allow more than one revision for each specific article; to parse a comprehensive dump file use the Parse::MediaWikiDump::Revisions object.

SYNOPSIS

$pmwd = Parse::MediaWikiDump->new;
$pages = $pmwd->pages('pages-articles.xml');
$pages = $pmwd->pages(\*FILEHANDLE);

#print the title and id of each article inside the dump file
while(defined($page = $pages->next)) {
  print "title '", $page->title, "' id ", $page->id, "\n";
}

METHODS

$pages->new

Open the specified MediaWiki dump file. If the single argument to this method is a string it will be used as the path to the file to open. If the argument is a reference to a filehandle the contents will be read from the filehandle as specified.

$pages->next

Returns an instance of the next available Parse::MediaWikiDump::page object or returns undef if there are no more articles left.

$pages->version

Returns a plain text string of the dump file format revision number

$pages->sitename

Returns a plain text string that is the name of the MediaWiki instance.

$pages->base

Returns the URL to the instances main article in the form of a string.

$pages->generator

Returns a string containing 'MediaWiki' and a version number of the instance that dumped this file. Example: 'MediaWiki 1.14alpha'

$pages->case

Returns a string describing the case sensitivity configured in the instance.

$pages->namespaces

Returns a reference to an array of references. Each reference is to another array with the first item being the unique identifier of the namespace and the second element containing a string that is the name of the namespace.

$pages->namespaces_names

Returns an array reference the array contains strings of all the namespaces each as an element.

$pages->current_byte

Returns the number of bytes that has been processed so far

$pages->size

Returns the total size of the dump file in bytes.

Scan an article dump file for double redirects that exist in the most recent article revision

#!/usr/bin/perl

#progress information goes to STDERR, a list of double redirects found
#goes to STDOUT

binmode(STDOUT, ":utf8");
binmode(STDERR, ":utf8");

use strict;
use warnings;
use Parse::MediaWikiDump;

my $file = shift(@ARGV);
my $pmwd = Parse::MediaWikiDump->new;
my $pages;
my $page;
my %redirs;
my $artcount = 0;
my $file_size;
my $start = time;

if (defined($file)) {
	$file_size = (stat($file))[7];
	$pages = $pmwd->pages($file);
} else {
	print STDERR "No file specified, using standard input\n";
	$pages = $pmwd->pages(\*STDIN);
}

#the case of the first letter of titles is ignored - force this option
#because the other values of the case setting are unknown
die 'this program only supports the first-letter case setting' unless
	$pages->case eq 'first-letter';

print STDERR "Analyzing articles:\n";

while(defined($page = $pages->next)) {
  update_ui() if ++$artcount % 500 == 0;

  #main namespace only
  next unless $page->namespace eq '';
  next unless defined($page->redirect);

  my $title = case_fixer($page->title);
  #create a list of redirects indexed by their original name
  $redirs{$title} = case_fixer($page->redirect);
}

my $redir_count = scalar(keys(%redirs));
print STDERR "done; searching $redir_count redirects:\n";

my $count = 0;

#if a redirect location is also a key to the index we have a double redirect
foreach my $key (keys(%redirs)) {
  my $redirect = $redirs{$key};

  if (defined($redirs{$redirect})) {
    print "$key\n";
    $count++;
  }
}

print STDERR "discovered $count double redirects\n";

#removes any case sensativity from the very first letter of the title
#but not from the optional namespace name
sub case_fixer {
  my $title = shift;

  #check for namespace
  if ($title =~ /^(.+?):(.+)/) {
    $title = $1 . ':' . ucfirst($2);
  } else {
    $title = ucfirst($title);
  }

  return $title;
}

sub pretty_bytes {
  my $bytes = shift;
  my $pretty = int($bytes) . ' bytes';

  if (($bytes = $bytes / 1024) > 1) {
    $pretty = int($bytes) . ' kilobytes';
  }

  if (($bytes = $bytes / 1024) > 1) {
    $pretty = sprintf("%0.2f", $bytes) . ' megabytes';
  }

  if (($bytes = $bytes / 1024) > 1) {
    $pretty = sprintf("%0.4f", $bytes) . ' gigabytes';
  }

  return $pretty;
}

sub pretty_number {
  my $number = reverse(shift);
  $number =~ s/(...)/$1,/g;
  $number = reverse($number);
  $number =~ s/^,//;

  return $number;
}

sub update_ui {
  my $seconds = time - $start;
  my $bytes = $pages->current_byte;

  print STDERR "  ", pretty_number($artcount),  " articles; "; 
  print STDERR pretty_bytes($bytes), " processed; ";

  if (defined($file_size)) {
    my $percent = int($bytes / $file_size * 100);

    print STDERR "$percent% completed\n"; 
  } else {
    my $bytes_per_second = int($bytes / $seconds);
    print STDERR pretty_bytes($bytes_per_second), " per second\n";
  }
}

LIMITATIONS

Version 0.4

This class was updated to support version 0.4 dump files from a MediaWiki instance but it does not currently support any of the new information available in those files.