The Code

This script uses a regular expression to match the special linking format inside any post. If the pattern is found, it replaces asin:ASIN with the proper URL. Add the following code to a file called asin (no extension necessary).

# Blosxom Plugin: ASIN
# Author: Nelson Minar <nelson@monkey.org>
# Version: 20030301
# http://www.nelson.monkey.org/~nelson/weblog/
# License: Public Domain

# ASIN is a Blosxom plugin that simplifies linking into Amazon's catalog.
# The link format is not a guaranteed standard, in particular the 
# ref=nosim part. For the authority see
# https://associates.amazon.com/exec/panama/associates/resources/build-&return;
links/individual-item-link.html

# Installation:
#   Modify the $associateID (or don't :-)
#   Drop asin into your plugins directory

package asin;

$associateID = 'insert associate ID';

sub start {
    1;
}

sub rewriteASIN {
    my ($url) = @_;
    $url =~ s%"asin:(.+)"%"\"http://www.amazon.com/exec/obidos/ASIN/&return;
$1/ref=nosim/$associateID\""%ies;
    return $url;    
}

# Modify the body of stories by rewriting asin: URIs to real URLs
sub story {
    my($pkg, $path, $filename, $story_ref, $title_ref, $body_ref) = @_;
    # Rewrite any <a href="asin:..."> tag in the post body
    $$body_ref =~ s/(<a\s[^>]*href="asin:[^>]+>)/rewriteASIN($1)/geis;
    1;
}

1;