[#4396] Moved ObjectsAPI views and urls to contrib, added basic plugi…

…n structure

docs/configuration/prefill/index.rst

@@ -12,3 +12,4 @@ Prefill plugins
    kvk
    stuf_bg
    suwinet
+   objects_api

docs/configuration/prefill/objects_api.rst

@@ -0,0 +1,43 @@
+.. todo:: This feature is still in development and not ready for production yet.
+
+.. _configuration_prefill_objects_api:
+
+===========
+Objects API
+===========
+
+The `Objects API`_ stores data records of which the structure and shape are defined by a particular object type
+definition in the `Objecttypes API`_. These records can be used to pre-fill form fields if an object reference is
+passed when the form is started.
+
+.. note::
+
+   The service may contain sensitive data. It is advised to require DigiD/eHerkenning authentication on the form. You
+   should be careful with how you pass the object references to the customers and set up the object type in a way that
+   makes authentication checks possible (e.g. by storing the expected BSN or KVK number).
+
+.. _`Objects API`: https://objects-and-objecttypes-api.readthedocs.io/en/latest/
+.. _`Objecttypes API`: https://objects-and-objecttypes-api.readthedocs.io/en/latest/
+
+
+Configuration
+=============
+
+1. In Open Forms, navigate to: **Forms**
+2. Click **Add form**
+3. Define the necessary form details and add the desired components
+4. Navigate to: **Variables** tab
+5. Navigate to: **User defined** subtab
+6. Click **Add variable** and fill in the data from the available options:
+   * **Plugin**: Choose the *Objects API* plugin
+   * **API Group**: Select the appropriate API group. These API groups should be set up by an administrator, 
+   via **Admin** > **Configuration** > **Prefill plugins** > **Objects API** > **Manage API groups**
+   * **Objecttype**: Select the expected object type from the dropdown.
+   * **Mappings**: Configure which property from the Objects API record needs to be assigned to which form variable. 
+   For each form variable you want to pre-fill, add a new mapping. Then, on the left select the desired form variable, 
+   and on the right you can specify which property from the object type contains the value.
+
+7. Click **Save**
+8. Save the form
+
+The Objects API configuration is now complete.

docs/developers/plugins/prefill_plugins.rst

@@ -25,6 +25,9 @@ You can find an example implementation in :mod:`openforms.prefill.contrib.demo`.
 Implementation
 --------------
 
+Plugins must be added to the ``INSTALLED_APPS`` setting in :mod:`openforms.conf.base`. See the demo 
+app (:class:`openforms.prefill.contrib.demo.apps.DemoApp`) as an example.
+
 Plugins must implement the interface from :class:`openforms.prefill.base.BasePlugin`.
 It's safe to use this as a base class.