cgi-bin/scraps/test.pl

   1 use CXGN::Page;
   2 use CXGN::Scrap;
   3 use Carp;
   4
   5
   6 ## Everything a scrap does should be enclosed in an eval{} statement to catch errors.
   7 eval {
   8
   9 my $scrap = CXGN::Scrap->new();
  10
  11 my %args = $scrap->get_all_encoded_arguments();
  12
  13 print<<HTML;
  14
  15 <html>
  16         <head><title>Scrap Test</title></head>
  17 <body style='font-family:arial, sans-serif'>
  18 This page is a scrap. It uses <b>CXGN::Scrap</b> as opposed to <b>CXGN::Page</b> to grab arguments.  This reduces overhead for things we don't need, such as standard SGN/Secretary page headers and footers.
  19 <br><br>
  20 The purpose of scraps is to receive arguments and perform database-related actions behind the scenes.  Generally, a scrap receives it's request via an <b>AJAX</b> method in <b>Javascript</b>. It should return some kind of simple textual reply that can be parsed by Javascript, but it doesn't really have to print anything at all.
  21 <br><br>
  22 This page wouldn't be an ideal scrap for Javascript-parsing since it contains html tagging and a little css, but you get the idea.
  23 <br><br>
  24 Try the following link to make sure the argument-getting is working:
  25 <a href='test.pl?something=intheway&esta_bien=1&yadda=kostanza'>This page, w/ args</a>
  26 &nbsp;&nbsp;
  27 <a href='test.pl'>This page, no args</a>
  28 <br><br>
  29 Here is a list of arguments sent to this scrap:
  30 HTML
  31
  32 while(my($key, $value) = each %args) {
  33         print "<br><em>Key:</em> $key => <em>Value:</em> $value";
  34 }
  35
  36
  37
  38 print <<EOF;
  39 <br><br>
  40 Here is the code for this page.  Notice that all of the scrap methods are enclosed in eval{} tags, so that an AJAX request does not receive an SGN error page, but rather a more simple Error expression that is parse-able:
  41
  42 <pre>
  43 use CXGN::Page;
  44 use CXGN::Scrap;
  45 use Carp;
  46
  47 ## Everything a scrap does should be enclosed in an eval{} statement to catch errors.
  48 eval {
  49
  50 my \$scrap = CXGN::Scrap->new();
  51
  52 my \%args = \$scrap->get_all_encoded_arguments();
  53
  54 print\<\<HTML;
  55
  56 <html>
  57         <head><title>Scrap Test</title></head>
  58
  59 ... Everything you see above ...
  60
  61 Here is a list of arguments sent to this scrap:
  62 HTML
  63
  64 while(my(\$key, \$value) = each \%args) {
  65         print "Key: \$key => Value: \$value";
  66 }
  67
  68 print <<HTML;
  69 </body></html>
  70 HTML
  71
  72 ## This is the preferred method for scraps to generate errors.  The standard SGN error page will be very difficult for Javascript to parse, in case a die, confess, or croak gets called.
  73 if(\$@) {
  74         print "Error: \$@";
  75         ##Everytime a scrap messes up, the AJAX request will begin with "Error:".  This allows JS-side error-catching to be handled fairly easily.
  76 }
  77
  78 EOF
  79
  80 };
  81 ## This is the preferred method for scraps to generate errors.  The standard SGN error page will be very difficult for Javascript to parse, in case a die, confess, or croak gets called.
  82 if($@) {
  83         print "Error: $@";
  84         ##Everytime a scrap messes up, the AJAX request will begin with "Error:".  This allows JS-side error-catching to be handled fairly easily.
  85 }
  86