Bad Cookie

#!/usr/bin/perl # # $Id: graph.png,v 1.25 2003/10/15 21:08:39 matthew Exp $ # # Copyright Michigan State University Board of Trustees # # This file is part of the LearningOnline Network with CAPA (LON-CAPA). # # LON-CAPA 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. # # LON-CAPA 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 LON-CAPA; if not, write to the Free Software # Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA # # /home/httpd/cgi-bin/graph.gif # # http://www.lon-capa.org/ # # The LearningOnline Network with CAPA # # A CGI script that dynamically outputs a graphical chart for lonstatistics. # #### =pod =head1 NAME graph.png =head1 SYNOPSIS produces plots based on input =head1 DESCRIPTION graph.png is a cgi-bin script which produces plots based on input data. The query string is expected to be as follows (without whitespace): escape(Plot title) & escape(X label)& escape(Y label) & Maximum Y value & Number of bars & $data1 & $data2 $data1 and $data2 are expected to be comma seperated lists of numbers. escape( value ) means the values must be run through lonnet::escape. =cut use strict; use lib '/home/httpd/lib/perl'; use GD::Graph::bars; use GD::Graph::colour; use GD::Graph::Data; use LONCAPA::loncgi(); sub unescape { my $str=shift; $str =~ s/%([a-fA-F0-9][a-fA-F0-9])/pack("C",hex($1))/eg; return $str; } if (! &LONCAPA::loncgi::check_cookie_and_load_env()) { print < Bad Cookie Your cookie information is incorrect. What\'s up with that? END return; } $|=1; # Autoflush after each print/write my $identifier = $ENV{'QUERY_STRING'}; my $Title = &unescape($ENV{$identifier.'.title'}); my $xlabel = &unescape($ENV{$identifier.'.xlabel'}); my $ylabel = &unescape($ENV{$identifier.'.ylabel'}); my $Max = $ENV{$identifier.'.Max'}; my $NumBars = $ENV{$identifier.'.NumBars'}; my $NumSets = $ENV{$identifier.'.NumSets'}; my @Colors = split(',',$ENV{$identifier.'.Colors'}); # # Labels are always digits my @xlabels; for (my $nIdx=0; $nIdx<$NumBars; $nIdx++ ) { $xlabels[$nIdx]=$nIdx+1; } my @data; # stores the data for the graph push(@data,\@xlabels); for (my $i=1;$i<=$NumSets;$i++) { push(@data,[split(',',$ENV{$identifier.'.data.'.$i})]); } my $skip_x = 1; my $bar_width=10; # # Customize graph based on the my $width; my $height = 200; if ($NumBars < 10) { $width = 120+$NumBars*15; $skip_x = 1; $bar_width = 15; } elsif ($NumBars <= 25) { $width = 120+$NumBars*11; $skip_x = 5; $bar_width = 8; } elsif ($NumBars <= 50) { $width = 120+$NumBars*8; $skip_x = 5; $bar_width = 4; } else { $width = 120+$NumBars*8; $skip_x = 5; $bar_width = 4; } my $x_tick_offset = 0; if ($skip_x > 1) { $x_tick_offset = $skip_x - 1; } my $MyGraph = GD::Graph::bars->new($width,$height); my $error = ''; if (! $MyGraph->set( x_label => $xlabel, y_label => $ylabel, x_label_position => 0.5, long_ticks => 1, tick_length => 0, x_ticks => 0, title => $Title, y_max_value => $Max, x_label_skip => $skip_x, x_tick_offset => $x_tick_offset, # dclrs => \@Colors, bar_width => $bar_width, cumulate => 2, zero_axis => 1, fgclr => 'black', boxclr => 'white', accentclr => 'dblue', valuesclr => '#ffff77', l_margin => 10, b_margin => 10, r_margin => 10, t_margin => 10, # transparent => 0, )) { $error = $MyGraph->error; print <<"END"; Content-type: text/html Bad Graph

There was an error producing the graph you requested.

$error

END return; } my $plot = $MyGraph->plot(\@data); if (! defined($plot)) { print <<"END"; Content-type: text/html Bad Graph The system was unable to create the graph you requested. END return; } my $BinaryData=$plot->png; undef($MyGraph); undef($plot); if (! defined($BinaryData)) { print <<"END"; Content-type: text/html Bad Graph The system was unable to produce a png image of the graph you requested. END return; } # Tell the server we are sending a png graphic print </dev/null"; # convert into a gif image #print IMG $BinaryData; # output image #$|=1; # be sure to flush before closing #close IMG; print $BinaryData;