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 WebService::RTMAgent - UserAgent for the RememberTheMilk API


 $ua = WebService::RTMAgent->new;
 $url = $ua->get_auth_url;  # then do something with the URL
 $res = $ua->tasks_getList('filter=status:incomplete');



WebService::RTMAgent is a Perl implementation of the API.

Calling API methods

All API methods documented at can be called as methods, changing dots for underscores and optionnaly taking off the leading 'rtm': $ua->auth_checkToken, $ua->tasks_add, etc.

Parameters should be given as a list of strings, e.g.:

 $ua->tasks_complete("list_id=4231233", "taskseries_id=124233", "task_id=1234");

Refer to the API documentation for each method's parameters.

Return values are the XML response, parsed through XML::Simple. Please refer to XML::Simple for more information (and Data::Dumper, to see what the values look like) and the sample rtm script for examples.

If the method call was not successful, undef is returned, and an error message is set which can be accessed with the error method:

 $res = $ua->tasks_getList;
 die $ua->error unless defined $res;

Please note that at this stage, I am not very sure that this is the best way to implement the API. "It works for me," but:

  • Parameters may turn to hashes at some point

  • Output values may turn to something more abstract and useful, as I gain experience with API usage.

Authentication and authorisation

Before using the API, you need to authenticate it. If you are going to be building a desktop application, you should get an API key and shared secret from the people at (see for rationale) and provide them to with the api_key and api_secret methods.

You then need to proceed through the authentication cycle: create a useragent, call the get_auth_url method and direct a Web browser to the URL it returns. There RememberTheMilk will present you with an authorisation page: you can authorise the API to access your account.

At that stage, the API will get a token which identifies the API/user authorisation. RTMAgent saves the token in a file, so you should never need to do the authentication again.

Proxy and other strange things

The object returned by new is also a LWP::UserAgent. This means you can configure it the same way, in particular to cross proxy servers:

 $ua = new WebService::RTMAgent;
 $ua->proxy('http', 'http://proxy:8080');
 $list = $ua->tasks_getList;

Incidentally, this is the reason why the init method exists: init needs to access the network, so its work cannot be done in new as that would leave no opportunity to configure the LWP UserAgent.


$ua = WebService::RTMAgent->new;

Creates a new agent.


Set the API key and secret. These are obtained from the people are

$ua->verbose('netin netout');

Sets what type of traces the module should print. You can use 'netout' to print all the outgoing messages, 'netin' to print all the incoming messages.

$err = $ua->error;

Get a message describing the last error that happened.


Performs authentication with RTM and various other book-keeping initialisations.


Performs the beginning of the authentication: this returns a URL to which the user must then go to allow RTMAgent to access his or her account.

This mecanism is slightly contrieved and designed so that users do not have to give their username and password to third party software (like this one).

@undo = $ua->get_undoable;

Returns the transactions which we know how to undo (unless data has been lost, that's all the undo-able transaction that go with the timeline that is saved in the state file).

The value returned is a list of { id, op, [ params ] } with id the transaction id, op the API method that was called, and params the API parameters that were called.


Removes an undo entry.


Don't use those and we'll stay friends.


Returns the md5 signature for signing parameters. See RTM Web site for details. This should only be useful for the module, don't use it.

$ua->rtm_request("rtm.tasks.getList", "list_id=234", "taskseries_id=2"..)

Signs the parameters, performs the request, returns a parsed XML::Simple object.



XML file containing runtime data: frob, timeline, authentication token. This file is overwritten on exit, which means you should only have one instance of RTMAgent (this should be corrected in a future version).


rtm, example command-line script. LWP. XML::Simple.


Written by Yves Rutschle <>


This software is free software; you may redistribute it and/or modify it under the same terms as Perl itself.