External API
============

.. sectionauthor:: Tom Needham <tom@owncloud.com>

Introduction
------------
The external API inside ownCloud allows third party developers to access data
provided by ownCloud apps. ownCloud follows the `OCS v1.7
specification <http://www.freedesktop.org/wiki/Specifications/open-collaboration-services-1.7>`_ (draft).

Usage
-----

Registering Methods
~~~~~~~~~~~~~~~~~~~
Methods are registered inside the :file:`appinfo/routes.php` using :php:class:`OCP\\API`

.. code-block:: php

  <?php

  \OCP\API::register(
      'get', 
      '/apps/yourapp/url', 
      function($urlParameters) {
      	return new \OC_OCS_Result($data);
      },
      'yourapp', 
      \OC_API::ADMIN_AUTH
  );

Returning Data
~~~~~~~~~~~~~~
Once the API backend has matched your URL, your callable function as defined in
**$action** will be executed. This method is passed as array of parameters that you defined in **$url**. To return data back the the client, you should return an instance of :php:class:`OC_OCS_Result`. The API backend will then use this to construct the XML or JSON response.

Authentication & Basics
~~~~~~~~~~~~~~~~~~~~~~~
Because REST is stateless you have to send user and password each time you access the API. Therefore running ownCloud **with SSL is highly recommended** otherwise **everyone in your network can log your credentials**::

    https://user:password@yourowncloud.com/ocs/v1.php/apps/yourapp


Output
~~~~~~
The output defaults to XML. If you want to get JSON append this to the URL::
    
    ?format=json

Output from the application is wrapped inside a **data** element:

**XML**:

.. code-block:: xml

    <?xml version="1.0"?>
    <ocs>
     <meta>
      <status>ok</status>
      <statuscode>100</statuscode>
      <message/>
     </meta>
     <data>
       <!-- data here -->
     </data>
    </ocs>


**JSON**:

.. code-block:: js

    {
      "ocs": {
        "meta": {
          "status": "ok",
          "statuscode": 100,
          "message": null
        },
        "data": {
          // data here
        }
      }
    }

Statuscodes
~~~~~~~~~~~
The statuscode can be any of the following numbers:

* **100** - successful
* **996** - server error
* **997** - not authorized
* **998** - not found
* **999** - unknown error
