NAME¶
Net::Amazon - Framework for accessing amazon.com via REST
SYNOPSIS¶
use Net::Amazon;
my $ua = Net::Amazon->new(
associate_tag => 'YOUR_AMZN_ASSOCIATE_TAG',
token => 'YOUR_AMZN_TOKEN',
secret_key => 'YOUR_AMZN_SECRET_KEY');
# Get a request object
my $response = $ua->search(asin => '0201360683');
if($response->is_success()) {
print $response->as_string(), "\n";
} else {
print "Error: ", $response->message(), "\n";
}
ABSTRACT¶
Net::Amazon provides an object-oriented interface to amazon.com's
REST interface. This way it's possible to create applications
using Amazon's vast amount of data via a functional interface, without
having to worry about the underlying communication mechanism.
DESCRIPTION¶
"Net::Amazon" works very much like "LWP": First you define a
useragent like
my $ua = Net::Amazon->new(
associate_tag => 'YOUR_AMZN_ASSOCIATE_TAG',
token => 'YOUR_AMZN_TOKEN',
secret_key => 'YOUR_AMZN_SECRET_KEY',
max_pages => 3,
);
which you pass your personal amazon developer's token (can be obtained from
<
http://amazon.com/soap>) and (optionally) the maximum number of result
pages the agent is going to request from Amazon in case all results don't fit
on a single page (typically holding 20 items). Note that each new page
requires a minimum delay of 1 second to comply with Amazon's
one-query-per-second policy.
According to the different search methods on Amazon, there's a bunch of
different request types in "Net::Amazon". The user agent's
convenience method "search()" triggers different request objects,
depending on which parameters you pass to it:
- "$ua->search(asin => "0201360683")"
- The "asin" parameter has Net::Amazon search for an item with the
specified ASIN. If the specified value is an arrayref instead of a single
scalar, like in
$ua->search(asin => ["0201360683", "0596005083"])
then a search for multiple ASINs is performed, returning a list of
results.
- "$ua->search(actor => "Adam Sandler")"
- The "actor" parameter has the user agent search for items
created by the specified actor. Can return many results.
- "$ua->search(artist => "Rolling Stones")"
- The "artist" parameter has the user agent search for items
created by the specified artist. Can return many results.
- "$ua->search(author => "Robert Jordan")"
- The "author" parameter has the user agent search for items
created by the specified author. Can return many results.
- "$ua->search(browsenode=>"4025",
mode=>"books" [, keywords=>"perl"])"
- Returns a list of items by category ID (node). For example node
"4025" is the CGI books category. You can add a keywords
parameter to filter the results by that keyword.
- "$ua->search(exchange => 'Y04Y3424291Y2398445')"
- Returns an item offered by a third-party seller. The item is referenced by
the so-called exchange ID.
- "$ua->search(keyword => "perl xml", mode =>
"books")"
- Search by keyword, mandatory parameters "keyword" and
"mode". Can return many results.
DETAILS Net::Amazon is based on Amazon Web Services version 4, and uses WSDL version 2011-08-01.¶
CACHING¶
Responses returned by Amazon's web service can be cached locally.
"Net::Amazon"'s "new" method accepts a reference to a
"Cache" object. "Cache" (or one of its companions like
"Cache::Memory", "Cache::File", etc.) can be downloaded
from CPAN, please check their documentation for details. In fact, any other
type of cache implementation will do as well, see the requirements below.
Here's an example utilizing a file cache which causes "Net::Amazon" to
cache responses for 30 minutes:
use Cache::File;
my $cache = Cache::File->new(
cache_root => '/tmp/mycache',
default_expires => '30 min',
);
my $ua = Net::Amazon->new(
token => 'YOUR_AMZN_TOKEN',
secret_key => 'YOUR_AMZN_SECRET_KEY',
cache => $cache,
);
"Net::Amazon" uses
positive caching only, errors won't be
cached. Erroneous requests will be sent to Amazon every time. Positive cache
entries are keyed by the full URL used internally by requests submitted to
Amazon.
Caching isn't limited to the "Cache" class. Any cache object which
adheres to the following interface can be used:
# Set a cache value
$cache->set($key, $value);
# Return a cached value, 'undef' if it doesn't exist
$cache->get($key);
COMPRESSION¶
By default "Net::Amazon" will attempt to use HTTP compression if the
Compress::Zlib module is available. Pass "compress => 0" to
"->new()" to disable this feature.
PROXY SETTINGS¶
"Net::Amazon" uses "LWP::UserAgent" under the hood to send
web requests to Amazon's web site. If you're in an environment where all Web
traffic goes through a proxy, there's two ways to configure that.
First, "Net::Amazon" picks up proxy settings from environment
variables:
export http_proxy=http://proxy.my.place:8080
in the surrounding shell or setting
$ENV{http_proxy} = "http://proxy.my.place:8080";
in your Perl script will route all requests through the specified proxy.
Secondly, you can pass a user agent instance to Net::Amazon's constructor:
use Net::Amazon;
use LWP::UserAgent;
my $ua = LWP::UserAgent->new();
my $na = Net::Amazon->new(
ua => $ua,
associate_tag => 'YOUR_AMZN_ASSOCIATE_TAG',
token => 'YOUR_AMZN_TOKEN',
secret_key => 'YOUR_AMZN_SECRET_KEY',
);
# ...
This way, you can configure $ua up front before Net::Amazon will use it.
DEBUGGING¶
If something's going wrong and you want more verbosity, just bump up
"Net::Amazon"'s logging level. "Net::Amazon" comes with
"Log::Log4perl" statements embedded, which are disabled by default.
However, if you initialize "Log::Log4perl", e.g. like
use Net::Amazon;
use Log::Log4perl qw(:easy);
Log::Log4perl->easy_init($DEBUG);
my Net::Amazon->new();
# ...
you'll see what's going on behind the scenes, what URLs the module is requesting
from Amazon and so forth. Log::Log4perl allows all kinds of fancy stuff, like
writing to a file or enabling verbosity in certain parts only -- check
http://log4perl.sourceforge.net for details.
LIVE TESTING¶
Results returned by Amazon can be incomplete or simply wrong at times, due to
their "best effort" design of the service. This is why the test
suite that comes with this module has been changed to perform its test cases
against canned data. If you want to perform the tests against the live Amazon
servers instead, just set the environment variable
NET_AMAZON_LIVE_TESTS=1
WHY ISN'T THERE SUPPORT FOR METHOD XYZ?¶
Because nobody wrote it yet. If Net::Amazon doesn't yet support a method
advertised on Amazon's web service, you could help us out. Net::Amazon has
been designed to be expanded over time, usually it only takes a couple of
lines to support a new method, the rest is done via inheritance within
Net::Amazon.
Here's the basic plot:
- •
- Get Net::Amazon from CVS. Use
# (Just hit enter when prompted for a password)
cvs -d:pserver:anonymous@cvs.net-amazon.sourceforge.net:/cvsroot/net-amazon login
cvs -z3 -d:pserver:anonymous@cvs.net-amazon.sourceforge.net:/cvsroot/net-amazon co Net-Amazon
If this doesn't work, just use the latest distribution from
net-amazon.sourceforge.net.
- •
- Write a new Net::Amazon::Request::XYZ package, start with this template
######################################
package Net::Amazon::Request::XYZ;
######################################
use base qw(Net::Amazon::Request);
######################################
sub new {
######################################
my($class, %options) = @_;
if(!exists $options{XYZ_option}) {
die "Mandatory parameter 'XYZ_option' not defined";
}
my $self = $class->SUPER::new(%options);
bless $self, $class; # reconsecrate
}
and add documentation. Then, create a new Net::Amazon::Response::XYZ module:
##############################
package Net::Amazon::Response;
##############################
use base qw(Net::Amazon::Response);
use Net::Amazon::Property;
##############################
sub new {
##############################
my($class, %options) = @_;
my $self = $class->SUPER::new(%options);
bless $self, $class; # reconsecrate
}
and also add documentation to it. Then, add the line
use Net::Amazon::Request::XYZ;
to Net/Amazon.pm.
And that's it! Again, don't forget the
add documentation part. Modules
without documentation are of no use to anybody but yourself.
Check out the different Net::Amazon::Request::* and Net::Amazon::Response
modules in the distribution if you need to adapt your new module to fulfil any
special needs, like a different Amazon URL or a different way to handle the
as_string() method. Also, post and problems you might encounter to the
mailing list, we're gonna help you out.
If possible, provide a test case for your extension. When finished, send a patch
to the mailing list at
net-amazon-devel@lists.sourceforge.net
and if it works, I'll accept it and will work it into the main distribution.
Your name will show up in the contributor's list below (unless you tell me
otherwise).
SAMPLE SCRIPTS¶
There's a number of useful scripts in the distribution's eg/ directory. Take
"power" for example, written by Martin Streicher
<martin.streicher@apress.com>: I lets you perform a
power search
using Amazon's query language. To search for all books written by Randal
Schwartz about Perl, call this from the command line:
power 'author: schwartz subject: perl'
Note that you need to quote the query string to pass it as one argument to
"power". If a power search returns more results than you want to
process at a time, just limit the number of pages, telling "power"
which page to start at ("-s") and which one to finish with
("-f"). Here's a search for all books on the subject
"computer", limited to the first 10 pages:
power -s 1 -f 10 'subject: computer'
Check out the script "power" in eg/ for more options.
HOW TO SEND ME PATCHES¶
If you want me to include your modification or enhancement in the distribution
of Net::Amazon, please do the following:
- •
- Work off the latest CVS version. Here's the steps to get it:
CVSROOT=:pserver:anonymous@cvs.net-amazon.sourceforge.net:/cvsroot/net-amazon
export CVSROOT
cvs login (just hit Enter)
cvs co Net-Amazon
This will create a new "Net-Amazon" directory with the latest
development version of "Net::Amazon" on your local machine.
- •
- Apply your changes to this development tree.
- •
- Run a diff between the tree and your changes it in this way:
cd Net-Amazon
cvs diff -Nau >patch_to_christopher.txt
- •
- Email me "patch_to_christopher.txt". If your patch works (and
you've included test cases and documentation), I'll apply it on the
spot.
INSTALLATION¶
"Net::Amazon" depends on Log::Log4perl, which can be pulled from CPAN
by simply saying
perl -MCPAN -eshell 'install Log::Log4perl'
Also, it needs LWP::UserAgent and XML::Simple 2.x, which can be obtained in a
similar way.
Once all dependencies have been resolved, "Net::Amazon" installs with
the typical sequence
perl Makefile.PL
make
make test
make install
Make sure you're connected to the Internet while running "make test"
because it will actually contact amazon.com and run a couple of live tests.
The module's distribution tarball and documentation are available at
http://perlmeister.com/devel/#amzn
and on CPAN.
SEE ALSO¶
The following modules play well within the "Net::Amazon" framework:
- "Net::Amazon::RemoteCart"
- by David Emery <dave@skiddlydee.com> provides a complete API for
creating Amazon shopping carts on a local site, managing them and finally
submitting them to Amazon for checkout. It is available on CPAN.
The "Net::Amazon" project's home page is hosted on
http://net-amazon.sourceforge.net
where you can find documentation, news and the latest development and stable
releases for download. If you have questions about how to use
"Net::Amazon", want to report a bug or just participate in its
development, please send a message to the mailing list
net-amazon-devel@lists.sourceforge.net
The source code has moved from sourceforge.net to github.com. The git URL is
git://github.com/boumenot/p5-Net-Amazon.git
The hope is that github.com makes collaboration much easier, and git is a much
more modern SCM tool.
AUTHOR¶
Mike Schilli, <na@perlmeister.com> (Please contact me via the mailing
list: net-amazon-devel@lists.sourceforge.net )
Maintainers: Christopher Boumenot, <boumenot+na@gmail.com>
Contributors (thanks y'all!):
Andy Grundman <andy@hybridized.org>
Barnaby Claydon <bclaydon@perseus.com>
Batara Kesuma <bkesuma@gaijinweb.com>
Bill Fitzpatrick
Brian <brianbrian@gmail.com>
Brian Hirt <bhirt@mobygames.com>
Dan Kreft <dan@kreft.net>
Dan Sully <daniel@electricrain.com>
Dave Cardwell <http://davecardwell.co.uk/>
Jackie Hamilton <kira@cgi101.com>
Konstantin Gredeskoul <kig@get.topica.com>
Lance Cleveland <lancec@proactivewm.com>
Martha Greenberg <marthag@mit.edu>
Martin Streicher <martin.streicher@apress.com>
Mike Evron <evronm@dtcinc.net>
Padraic Renaghan <padraic@renaghan.com>
rayg <rayg@varchars.com>
Robert Graff <rgraff@workingdemo.com>
Robert Rothenberg <wlkngowl@i-2000.com>
Steve Rushe <steve@deeden.co.uk>
Tatsuhiko Miyagawa <miyagawa@livedoor.jp>
Tony Bowden <tony@kasei.com>
Vince Veselosky
COPYRIGHT AND LICENSE¶
Copyright 2003, 2004 by Mike Schilli <na@perlmeister.com> Copyright
2007-2009 by Christopher Boumenot <boumenot+na@gmail.com>
This library is free software; you can redistribute it and/or modify it under
the same terms as Perl itself.