def inasafe_fields_for_the_layer(self):
        """Return a list of inasafe fields the current layer.

        :returns: A list where each value represents inasafe field.
        :rtype: list
        """
        if (self.parent.get_layer_geometry_key()
                == layer_geometry_raster['key']):
            return []
        # Get hazard or exposure value
        layer_purpose_key = self.parent.step_kw_purpose.selected_purpose()[
            'key']
        if layer_purpose_key != layer_purpose_aggregation['key']:
            subcategory_key = self.parent.step_kw_subcategory.\
                selected_subcategory()['key']
        else:
            subcategory_key = None
        # Get all fields with replace_null = False
        inasafe_fields = get_fields(
            layer_purpose_key,
            subcategory_key,
            replace_null=False,
            in_group=False)
        # remove compulsory field since it has been set in previous step
        try:
            inasafe_fields.remove(get_compulsory_fields(
                layer_purpose_key, subcategory_key))
        except ValueError:
            pass
        return inasafe_fields
Return a list of inasafe fields the current layer.

        :returns: A list where each value represents inasafe field.
        :rtype: list