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APIv3 Chaining

It is now possible to do two API calls at once with the first call feeding into the second. E.g. to create a contact with a contribution you can nest the contribution create into the contact create. Once the contact has been created it will action the contribution create using the id from the contact create as contact_id. Likewise you can ask for all activities or all contributions to be returned when you do a get.

See api/v3/examples within the core source code for a plethora of examples (from unit tests) that use chaining. To start, look at these examples:

Note that there are a few supported syntaxes:

civicrm_api('Contact', 'create', array(
  'version' => 3,
  'contact_type' => 'Individual',
  'display_name' => 'BA Baracus',
  'api.website.create' => array('url' => 'example.com'),
));

is the same as

civicrm_api('Contact', 'create', array(
  'version' => 3,
  'contact_type' => 'Individual',
  'display_name' => 'BA Baracus',
  'api.website' => array('url' => 'example.com'),
));

If you have 2 websites to create you can pass them as ids after the . or an array

civicrm_api('Contact', 'create', array(
  'version' => 3,
  'contact_type' => 'Individual',
  'display_name' => 'BA Baracus',
  'api.website.create' => array('url' => 'example.com'),
  'api.website.create.2' => array('url' => 'example.org'),
));

or

civicrm_api('Contact', 'create', array(
  'version' => 3,
  'contact_type' => 'Individual',
  'display_name' => 'BA Baracus',
  'api.website.create' => array(
    array('url' => 'example.com'),
    array('url' => 'example.org'),
  ),
));

The format you use on the way in will dictate the format on the way out.

Currently this supports any entity and it will convert to entity_id - i.e. a PledgePayment inside a contribution will receive the contribution_id from the outer call.