Parsing ASP files

thewebsi has asked for the wisdom of the Perl Monks concerning the following question:

I am looking to parse web site files to enable some simple manipulations (wrapping certain bits of plain text in custom tags). HTML::Parser is sufficient for this (HTML::TreeBuilder is probably overkill). However, some of the web site files contain an embedded tag language (eg, ASP, JSP, PHP). HTML::Parser does not recognize these tags (<% ... %>, etc), and produces some unfavourable results in these cases (I'd like it to treat them like regular tags and just ignore them). I don't see a way to extend HTML::Parser to handle such files.

Is there: A way to extend HTML::Parser? Another module I could use? Should I build my own parser with regex? I found these postings, and they both suggest I build my own parser for this: 1, 2, but thought I'd double-check in case there is a better way.

In case more detail is needed, I include my naive test script below:

#!/usr/bin/perl

use HTML::PullParser;

my $doc = <<'EOF'; my %options = ();
<input value="abc" /> abc &nbsp; abc
<% abc ( '<input value="abc" /> abc &nbsp; abc <span> %>', $abc ); %>
EOF

foreach ( qw{ start end comment declaration default process text } )
  { $options{$_} = "\"$_\", text"; }
my $p = HTML::PullParser->new ( doc => $doc, %options );

my $output = "";
print "DEBUG ---------------------------------------------------------
+-----\n";
while ( my $token = $p->get_token() )
{ 
  print "$token->[0]: '$token->[1]'\n";
  my $text = $token->[1];
  $text =~ s|abc|<b>abc</b>|g if $token->[0] eq 'text';
  $output .= $text;
}
print "---------------------------------------------------------------
+-----\n";

print $output;
[download]

Desired output:

<input value="abc" /> <b>abc</b> &nbsp; <b>abc</b>
<% abc ( '<input value="abc" /> abc &nbsp; abc <span> %>', $abc ); %>
[download]

Actual output:

<input value="abc" /> <b>abc</b> &nbsp; <b>abc</b>
<% <b>abc</b> ( '<input value="abc" /> <b>abc</b> &nbsp; <b>abc</b> <s
+pan> %>', $<b>abc</b> ); %>
[download]

Arnon Weinberg Back2Front - The Web Site People

Comment on Parsing ASP files Select or Download Code

Replies are listed 'Best First'.
Re: Parsing ASP files by Anonymous Monk on Jan 24, 2012 at 21:52 UTC
Yup, i'm pretty sure you'll have to preprocess You can glean some regexes from http://search.cpan.org/~johnd/ASP4-1.073/ http://cpansearch.perl.org/src/JOHND/ASP4-1.073/lib/ASP4/PageParser.pm #!/usr/bin/perl -- use strict; use warnings; my $asp = <<'__HTML__'; <input value="abc" /> abc   abc <% abc ( '<input value="abc" /> abc   abc <span> %>', $abc ); %> __HTML__ use HTML::Tree; my $t = 'HTML::TreeBuilder'->new; $t->ignore_unknown(0); $t->parse( $asp ); $t->dump; print "\n\n"; $asp =~ s{ <% ((?: '[^']+' \| "[^"]+' \| \$?[\w\s;,]+ \| [^%]+ )+) %> }{ my $content = $1; HTML::Entities::encode_entities( $content ); qq'<yoASP content="$content">' }gsex; $t->parse( $asp ); $t->dump; print "\n\n"; #~ and reverse it $asp =~ s/<yoASP content="([^"]+)">/ my $content = $1; HTML::Entities::decode_entities( $content ); $content; /gsei; print "$asp\n\n"; __END__ <html> @0 (IMPLICIT) <head> @0.0 (IMPLICIT) <body> @0.1 (IMPLICIT) <input value="abc" /> @0.1.0 " abc á abc <% abc ( '" <input value="abc" /> @0.1.2 " abc á abc " <span> @0.1.4 " %>', $abc ); %>" <html> @0 (IMPLICIT) <head> @0.0 (IMPLICIT) <body> @0.1 (IMPLICIT) <input value="abc" /> @0.1.0 " abc á abc <% abc ( '" <input value="abc" /> @0.1.2 " abc á abc " <span> @0.1.4 " %>', $abc ); %> " <input value="abc" /> @0.1.4.1 " abc á abc " <yoasp content=" abc ( '<input value="abc" /&gt +; abc &nbsp; abc <span> %>', $abc ); "> @0.1.4.3 <input value="abc" /> abc   abc abc ( '<input value="abc" /> abc   abc <span> %>', $abc ); [download]	[reply] [d/l]
Re^2: Parsing ASP files by thewebsi (Scribe) on Jan 26, 2012 at 04:57 UTC
Awesome! The test script is now working great: #!/usr/bin/perl use HTML::PullParser; use HTML::Entities; my $doc = <<'EOF'; my %options = (); <input value="abc" /> abc   abc <% abc ( '<input value="abc" /> abc   abc <span> %>', $abc ); %> EOF $doc =~ s{ <% ((?: '[^']+' \| "[^"]+' \| \$?[\w\s;,]+ \| [^%]+ )+) %> }{ my $content = $1; HTML::Entities::encode_entities ( $content ); qq'<asp_pp content="$content">' }gsex; foreach ( qw{ start text default } ) { $options{$_} = "'$_', text, tagname, attr"; } my $p = HTML::PullParser->new ( doc => $doc, %options ); my $output = ""; while ( my $token = $p->get_token() ) { my $text = $token->[1]; $text =~ s\|abc\|<b>abc</b>\|g if $token->[0] eq 'text'; $text = "<%$token->[3]->{content}%>" if $token->[0] eq 'start' and $token->[2] eq 'asp_pp'; $output .= $text; } print $output; [download] Arnon Weinberg Back2Front - The Web Site People	[reply] [d/l]
Re^3: Parsing ASP files by thewebsi (Scribe) on Apr 05, 2012 at 03:47 UTC
Looks like I spoke too soon. For anyone else attempting something similar, the above code had a flaw illustrated by the last line I added to the $doc test string below. The solution I came up with essentially amounts to using a more benign format for the temporary replacement string used to hide ASP code from HTML::Parser: #!/usr/bin/perl use HTML::PullParser; use HTML::Entities; my $doc = <<'EOF'; my %options = (); <input value="abc" /> abc   abc <% abc ( '<input value="abc" /> abc   abc <span> %\>', $abc ); %> <input value="<%= $abc %>" abc /> EOF $doc =~ s/<%(.*?)%>/ my $content = $1; HTML::Entities::encode_entities ( $content ); qq'[[asp_pp"$content"asp_pp]]' /gsex; foreach ( qw{ text default } ) { $options{$_} = "event, text, is_cdata"; } my $p = HTML::PullParser->new ( doc => $doc, %options ); my $output = ""; while ( my $token = $p->get_token() ) { my $text = $token->[1]; $text =~ s/(\[\[asp_pp"[^"]+"asp_pp\]\])\|(abc)/$1?$1:"<b>$2<\/b>"/gs +e if $token->[0] eq 'text' and ! $token->[2]; $output .= $text; } $output =~ s/\[\[asp_pp"([^"]+)"asp_pp\]\]/ "<%" . HTML::Entities::decode_entities ( $1 ) . "%>"/gse; print $output; [download] Output: `<input value="abc" /> <b>abc</b>   <b>abc</b> <% abc ( '<input value="abc" /> abc   abc <span> %>', $abc ); %> <input value="<%= $abc %>" abc />` [download] Arnon Weinberg Back2Front - The Web Site People	[reply] [d/l] [select]