Dear monks,

I'm trying to parse an ATOM feed and only want a few of the data in certain fields (updated, georss:point, which = the location in +/- format, and the time of the occurrence, which is in a CDATA field).

I was thinking to use XML::Rules to parse out the georss:point field and from there decide how to extract and parse the CDATA Time stamp but I can't get past the initial run - I get a:

"not well-formed (invalid token) at line 1, column 25, byte 25 at quake_parsing_4a1.pl line 22" response when I add in the rules and try to parse the xml. What am I doing wrong?

I welcome suggestions on how to debug this. Thanks for your suggestions!

A snippet of the feed: 

<entry>
<id>urn:earthquake-usgs-gov:us:c000hkbe</id>
<title>M 4.9 - 71km SW of Paita, Peru</title>
<updated>2013-06-10T16:39:37.373Z</updated>
<link rel="alternate" type="text/html" href="http://earthquake.usgs.go
+v/earthquakes/eventpage/usc000hkbe"/>
<link rel="alternate" type="application/cap+xml" href="http://earthqua
+ke.usgs.gov/earthquakes/eventpage/usc000hkbe.cap"/>
<summary type="html">
<![CDATA[
<p class="quicksummary"><a href="http://earthquake.usgs.gov/earthquake
+s/eventpage/usc000hkbe#dyfi" class="mmi-I" title="Did You Feel It? ma
+ximum reported intensity (0 reports)">DYFI? - <strong class="roman">I
+</strong></a></p><dl><dt>Time</dt><dd>2013-06-10 14:21:17 UTC</dd><dd
+>2013-06-10 09:21:17 -05:00 at epicenter</dd><dt>Location</dt><dd>5.5
+45&deg;S 81.572&deg;W</dd><dt>Depth</dt><dd>47.92 km (29.78 mi)</dd><
+/dl>
]]>
</summary>
<georss:point>-5.5453 -81.5723</georss:point>
<georss:elev>-47920</georss:elev>
<category label="Age" term="Past Day"/>
<category label="Magnitude" term="Magnitude 4"/>
</entry>

[download]

and then my code: 

#!/usr/bin/perl -w

use XML::FeedPP;
use XML::LibXML;
use XML::Rules;
use LWP::Simple;
use strict;
use warnings;

# get the Atom feed from the USGS

my $source = 'http://earthquake.usgs.gov/earthquakes/feed/v1.0/summary
+/4.5_day.atom';
my $feed = XML::FeedPP->new( $source );

# Incorporating a rules section so that we can extract the information
+ from the CDATA section
# and any other specific fields we might need.  First attempt will be 
+to pull the 'Updated'
# field data from the Atom feed.  I tried to follow the example in the
+ CPAN summary but I'm
# clearly lost.  

my @rules = (
         _default => sub {$_[0] => $_[1]->{_content}},
         id => sub {$_[0] => $_[1]->{_content}},
         author => undef, # ignorning the author because I already kno
+w it's the USGS
         updated => sub {print "$_[1]->{updated}\n";
         },
);

my $parser = XML::Rules->new(rules => \@rules);
$parser->parse( $feed );

# This section extracts the title field, then performs string manipula
+tions to extract the
# long location data and the magnitude.  Funny that USGS does not have
+ a magnitude field
# in this feed.

foreach my $quake( $feed->get_item() ) {
    my $title = $quake->title();
    my $place = substr($title, 8);
    my $magnitude = substr($title, 2,3);
#    my $id = $quake->get( $id );   # note that my attempt to get fiel
+d data did not work.  
#    my $update = $quake->updated();
#    my $location = $quake->'georss:point'();
    print "Magnitude ", $magnitude, " about ", $place, "\n";
}

[download]

thoughts?

In reply to One more parsing ATOM question by mcoblentz

Title:
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