.. _data:

Metadata manipulation
=====================

There are two possible ways to manipulate extra metadata in geonode:

- via Metadata Editor (Wizard and advanced)
- via Rest API


Metadata Editor (wizard/advanced):
----------------------------------

The metadata section is placed under the OPTIONAL METADATA section available for all the GeoNode resources.

The metadata must follow two specific rules to save to the resource:

- Must always be a list of JSON. This permits to add of more than one metadata for each resource
- The JSON must follow the schema defined in the `settings.py` for the selected resource.

For example, for my document resource, I can have something like the following:

.. figure:: img/wizard.png
     :align: center

     *Advanced edit wizard menù*

After pressing the save button, the system will perform the following checks:

- Check if the text provided is a valid JSON. In case of wrong format input, the following error is shown:

.. figure:: img/invalid_json.png
     :align: center

     *invalid JSON error*

- Check if the metadata schema is provided for the resource if not will raise the following error

.. figure:: img/missing_schema.png
     :align: center

     *missing schema error*

- Check if the metadata schema is coherent with the schema defined in the settings. In case of wrong format input, the error will print the missing JSON keys

.. figure:: img/invalid_schema.png
     :align: center

     *invalid schema error*

Facet Filtering
---------------

Automatically the web interface will create dynamically the facets if there is at least 1 metadata defined for the resource.

Suppose that a resource heve the following metadata:

.. code-block:: json

     [
          {
               "field_name": "bike",
               "field_label": "KTM",
               "field_value": "ktm",
               "filter_header": "Sports Parameters"
          },
          {
               "field_name": "mountain",
               "field_label": "Monte bianco",
               "field_value": "monte_bianco",
               "filter_header": "Italian Mountains"
          }
     ]

By default GeoNode will convert this metadata info in facets available for the resource

The facet will convert:
- `filter_header`: used as the header filter
- `field_value`: used to perform the search
- `field_name`: used for calculate the unique values (along with `field_value`)

After says that, the facet will be the follow:

.. figure:: img/facet.png
     :align: center