Provided by: libxml-atom-perl_0.42-2_all 
NAME
XML::Atom::Server - A server for the Atom API
SYNOPSIS
package My::Server;
use base qw( XML::Atom::Server );
sub handle_request {
my $server = shift;
$server->authenticate or return;
my $method = $server->request_method;
if ($method eq 'POST') {
return $server->new_post;
}
...
}
my %Passwords;
sub password_for_user {
my $server = shift;
my($username) = @_;
$Passwords{$username};
}
sub new_post {
my $server = shift;
my $entry = $server->atom_body or return;
## $entry is an XML::Atom::Entry object.
## ... Save the new entry ...
}
package main;
my $server = My::Server->new;
$server->run;
DESCRIPTION
XML::Atom::Server provides a base class for Atom API servers. It handles all core server
processing, both the SOAP and REST formats of the protocol, and WSSE authentication. It
can also run as either a mod_perl handler or as part of a CGI program.
It does not provide functions specific to any particular implementation, such as posting
an entry, retrieving a list of entries, deleting an entry, etc. Implementations should
subclass XML::Atom::Server, overriding the handle_request method, and handle all functions
such as this themselves.
SUBCLASSING
Request Handling
Subclasses of XML::Atom::Server must override the handle_request method to perform all
request processing. The implementation must set all response headers, including the
response code and any relevant HTTP headers, and should return a scalar representing the
response body to be sent back to the client.
For example:
sub handle_request {
my $server = shift;
my $method = $server->request_method;
if ($method eq 'POST') {
return $server->new_post;
}
## ... handle GET, PUT, etc
}
sub new_post {
my $server = shift;
my $entry = $server->atom_body or return;
my $id = save_this_entry($entry); ## Implementation-specific
$server->response_header(Location => $server->uri . '/entry_id=' . $id);
$server->response_code(201);
$server->response_content_type('application/x.atom+xml');
return serialize_entry($entry); ## Implementation-specific
}
Authentication
Servers that require authentication for posting or retrieving entries or feeds should
override the password_for_user method. Given a username (from the WSSE header),
password_for_user should return that user's password in plaintext. This will then be
combined with the nonce and the creation time to generate the digest, which will be
compared with the digest sent in the WSSE header. If the supplied username doesn't exist
in your user database or alike, just return "undef".
For example:
my %Passwords = ( foo => 'bar' ); ## The password for "foo" is "bar".
sub password_for_user {
my $server = shift;
my($username) = @_;
$Passwords{$username};
}
METHODS
XML::Atom::Server provides a variety of methods to be used by subclasses for retrieving
headers, content, and other request information, and for setting the same on the response.
Client Request Parameters
• $server->uri
Returns the URI of the Atom server implementation.
• $server->request_method
Returns the name of the request method sent to the server from the client (for
example, "GET", "POST", etc). Note that if the client sent the request in a SOAP
envelope, the method is obtained from the SOAPAction HTTP header.
• $server->request_header($header)
Retrieves the value of the HTTP request header $header.
• $server->request_content
Returns a scalar containing the contents of a POST or PUT request from the client.
• $server->request_param($param)
XML::Atom::Server automatically parses the PATH_INFO sent in the request and breaks it
up into key-value pairs. This can be used to pass parameters. For example, in the URI
http://localhost/atom-server/entry_id=1
the entry_id parameter would be set to 1.
request_param returns the value of the value of the parameter $param.
Setting up the Response
• $server->response_header($header, $value)
Sets the value of the HTTP response header $header to $value.
• $server->response_code([ $code ])
Returns the current response code to be sent back to the client, and if $code is
given, sets the response code.
• $server->response_content_type([ $type ])
Returns the current Content-Type header to be sent back to the client, and $type is
given, sets the value for that header.
Processing the Request
• $server->authenticate
Attempts to authenticate the request based on the authentication information present
in the request (currently just WSSE). This will call the password_for_user method in
the subclass to obtain the cleartext password for the username given in the request.
• $server->atom_body
Returns an XML::Atom::Entry object containing the entry sent in the request.
USAGE
Once you have defined your server subclass, you can set it up either as a CGI program or
as a mod_perl handler.
A simple CGI program would look something like this:
#!/usr/bin/perl -w
use strict;
use My::Server;
my $server = My::Server->new;
$server->run;
A simple mod_perl handler configuration would look something like this:
PerlModule My::Server
<Location /atom-server>
SetHandler perl-script
PerlHandler My::Server
</Location>
ERROR HANDLING
If you wish to return an error from handle_request, you can use the built-in error method:
sub handle_request {
my $server = shift;
...
return $server->error(500, "Something went wrong");
}
This will be returned to the client with a response code of 500 and an error string of
"Something went wrong". Errors are automatically serialized into SOAP faults if the
incoming request is enclosed in a SOAP envelope.
AUTHOR & COPYRIGHT
Please see the XML::Atom manpage for author, copyright, and license information.