source: main/trunk/greenstone2/perllib/downloaders/WebDownload.pm@ 31857

###########################################################################
#
# WebDownload.pm -- base class for all the import plugins
# A component of the Greenstone digital library software
# from the New Zealand Digital Library Project at the 
# University of Waikato, New Zealand.
#
# Copyright (C) 1999 New Zealand Digital Library Project
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2 of the License, or
# (at your option) any later version.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
#
###########################################################################

package WebDownload;

eval {require bytes};

# suppress the annoying "subroutine redefined" warning that various
# plugins cause under perl 5.6
$SIG{__WARN__} = sub {warn($_[0]) unless ($_[0] =~ /Subroutine\s+\S+\sredefined/)};

use WgetDownload;

sub BEGIN {
    @WebDownload::ISA = ('WgetDownload');
}

use strict; # every perl program should have this!
no strict 'refs'; # make an exception so we can use variables as filehandles

my $arguments = 
    [ { 'name' => "url", 
    'disp' => "{WebDownload.url_disp}",
    'desc' => "{WebDownload.url}",
    'type' => "string",
    'reqd' => "yes"},
      { 'name' => "depth", 
    'disp' => "{WebDownload.depth_disp}",
    'desc' => "{WebDownload.depth}",
    'type' => "int",
    'deft' => "0",
    "range" => "0,",
    'reqd' => "no"},
      { 'name' => "below", 
    'disp' => "{WebDownload.below_disp}",
    'desc' => "{WebDownload.below}",
    'type' => "flag",
    'reqd' => "no"},
      { 'name' => "within", 
    'disp' => "{WebDownload.within_disp}",
    'desc' => "{WebDownload.within}",
    'type' => "flag",
    'reqd' => "no"},
      { 'name' => "html_only", 
    'disp' => "{WebDownload.html_only_disp}",
    'desc' => "{WebDownload.html_only}",
    'type' => "flag",
    'reqd' => "no"}
      ];

my $options = { 'name'     => "WebDownload",
        'desc'     => "{WebDownload.desc}",
        'abstract' => "no",
        'inherits' => "yes",
        'args'     => $arguments };


my $self;

sub new 
{
    my ($class) = shift (@_);
    my ($getlist,$inputargs,$hashArgOptLists) = @_;
    push(@$getlist, $class);

    push(@{$hashArgOptLists->{"ArgList"}},@{$arguments});
    push(@{$hashArgOptLists->{"OptList"}},$options);

    my $self = new WgetDownload($getlist,$inputargs,$hashArgOptLists);
    
    return bless $self, $class;
}

sub download
{
    my ($self) = shift (@_);
    my ($hashGeneralOptions) = @_;

  
    # Download options
    my $strOptions = $self->generateOptionsString();
    my $strWgetOptions = $self->getWgetOptions();
      
    # Setup the command for using wget
    my $cache_dir = "";
    if($hashGeneralOptions->{'cache_dir'}) { # don't provide the prefix-dir flag to wget unless the cache_dir is specified
    if ($ENV{'GSDLOS'} eq "windows") {    
        $cache_dir = "-P \"".$hashGeneralOptions->{'cache_dir'}."\" ";
    }
    else {
        $cache_dir = "-P ".$hashGeneralOptions->{'cache_dir'};
    }
    }
    #my $cmdWget = "-N -k -x -t 2 -P \"".$hashGeneralOptions->{"cache_dir"}."\" $strWgetOptions $strOptions ".$self->{'url'};
    my $cmdWget = "-N -k -x --tries=2 $strWgetOptions $strOptions $cache_dir " .$self->{'url'};

    #print STDOUT "\n@@@@ RUNNING WGET CMD: $cmdWget\n\n";
    
    # Download the web pages
    # print "Start download from $self->{'url'}...\n";
    print STDERR "<<Undefined Maximum>>\n";
    
    if ($ENV{'GSDLOS'} eq "windows") {
    my $strResponse = $self->useWget($cmdWget,1);
    } else {
    my $strResponse = $self->useWget($cmdWget,1,$hashGeneralOptions->{"cache_dir"} );
    
    }
    
    # if ($strResponse ne ""){print "$strResponse\n";}
     print STDERR "Finish download from $self->{'url'}\n";

    print STDERR "<<Finished>>\n";
  
    return 1;
}

sub generateOptionsString
{
    my ($self) = @_;
    my $strOptions;

    (defined $self) || &error("generateOptionsString","No \$self is defined!!\n");
    (defined $self->{'depth'})|| &error("generateOptionsString","No depth is defined!!\n");
    
   
    if($self->{'depth'} == 0)
    {
    $strOptions .= " ";
    }
    elsif($self->{'depth'} > 0)
    {
    $strOptions .= "-r -l ".$self->{'depth'}." ";
    }
    else
    {
    $self->error("setupOptions","Incorrect Depth is defined!!\n");
    }

    if($self->{'below'})
    {
    $strOptions .="-np ";
    }

     if($self->{'html_only'})
    {
    $strOptions .="-A .html,.htm,.shm,.shtml,.asp,.php,.cgi,*?*=* ";
    }
    else{

    $strOptions .="-p ";
    }

    if (!$self->{'within'}){
    $strOptions .="-H ";
    }

    return $strOptions;
  
}

sub url_information
{
    my ($self) = shift (@_);

    my $strOptions = $self->getWgetOptions();

    my $strBaseCMD = $strOptions." --tries=2 -q -O - \"$self->{'url'}\"";

  
    my $strIdentifyText = $self->useWget($strBaseCMD);
    
    if (!defined $strIdentifyText or $strIdentifyText eq ""  ){
        print STDERR "Server information is unavailable.\n";            
        if ($self->{'proxy_on'} && $self->{'proxy_host'} && $self->{'proxy_port'}) { # if proxying set, the settings may be wrong
            print STDERR "Current proxy settings are:\n";
            print STDERR "- host=$self->{'proxy_host'}\n";
            print STDERR "- port=$self->{'proxy_port'}\n";
        } else { # else no proxy set, the user may need proxy settings
            print STDERR "The external server might not be responding, or you might need to switch on proxy settings.\n";
        }
        print STDERR "<<Finished>>\n";
         return;  
    }

    while ($strIdentifyText =~ m/^(.*)<title>(.*?)<\/title>(.*)$/si)
    {
    $strIdentifyText = $1.$3;
    print STDERR "Page Title: $2\n";
    }
  
    while ($strIdentifyText =~ m/^(.*)<meta (.*?)>(.*)$/si)
    {
    $strIdentifyText = $1.$3;
    my $strTempString = $2;
    print STDERR "\n";

    while($strTempString =~ m/(.*?)=[\"|\'](.*?)[\"|\'](.*?)$/si)
    {
        # Store the infromation in to variable, since next time when we do 
        # regular expression, we will lost all the $1, $2, $X....
        $strTempString = $3;
        my $strMetaName = $1;
        my $strMetaContain = $2;
        
        # Take out the extra space in the beginning of the string.
        $strMetaName =~ s/^([" "])+//m;
        $strMetaContain =~ s/^([" "])+//m;
              
        print STDERR "$strMetaName: $strMetaContain\n\n";
           
    }

    }

    print STDERR "<<Finished>>\n";

}


sub error
{
    my ($strFunctionName,$strError) = @_;
    {
    print "Error occoured in WebDownload.pm\n".
        "In Function:".$strFunctionName."\n".
        "Error Message:".$strError."\n";
    exit(-1);
    }
}

1;