Added customization of export/import data via user defined functions (#…

…20)

README.rst

@@ -57,6 +57,52 @@ For a manual install:
 * run ``python manage.py migrate djangocms_transfer``
 
 
+Customization
+-------------
+
+Following settings are available:
+
+* **DJANGOCMS_TRANSFER_PROCESS_EXPORT_PLUGIN_DATA**:
+
+  Enables processing of plugin instances prior to serialization, e.g.
+  ``myapp.module.function``.
+
+* **DJANGOCMS_TRANSFER_PROCESS_IMPORT_PLUGIN_DATA**:
+
+  Enables processing of plugin instances prior to saving, e.g.
+  ``myapp.module.function``.
+  For example: set default-values for ForeignKeys (images for django_filer, ..)
+
+As an example the combination of ``_PROCESS_EXPORT_PLUGIN_DATA`` and
+``_PROCESS_IMPORT_PLUGIN_DATA`` lets you export and import the data between
+different systems while setting the contents as you need it::
+
+    # settings.py
+    .._PROCESS_EXPORT_PLUGIN_DATA = "myapp.some.module.export_function"
+    .._PROCESS_IMPORT_PLUGIN_DATA = "myapp.some.module.import_function"
+
+    # custom functions
+    def export_function(plugin, plugin_data):
+        # remove child-plugins which can't be handled
+        if plugin.parent_id and plugin.parent.plugin_type == "SomeParentPlugin":
+            return None
+        # change data
+        if plugin.plugin_type == "SomePlugin":
+            plugin_data["data"].update({
+                "some_field": "TODO: change me",
+            })
+        return plugin_data
+
+    def import_function(deserialized_object):
+        some_related_object = MyModel.objects.first()
+        for field in deserialized_object.object._meta.fields:
+            # example of setting a default value for a related field
+            if isinstance(field, ForeignKey):
+                value = getattr(deserialized_object.object, field.attname)
+                if field.related_model == MyModel and value is not None:
+                    setattr(deserialized_object.object, field.name, some_related_object)
+
+
 Running Tests
 -------------
 

djangocms_transfer/datastructures.py

@@ -1,6 +1,7 @@
 from collections import namedtuple
 
 from django.core.serializers import deserialize
+from django.conf import settings
 from django.db import transaction
 from django.utils.encoding import force_str
 from django.utils.functional import cached_property
@@ -55,6 +56,13 @@ def restore(self, placeholder, language, parent=None, with_data=True):
             _d_instance.object._no_reorder = True
             _d_instance.object.cmsplugin_ptr = plugin
             plugin.set_base_attr(_d_instance.object)
+
+            # customize plugin-data on import with configured function
+            pps = getattr(settings, "DJANGOCMS_TRANSFER_PROCESS_IMPORT_PLUGIN_DATA", None)
+            if pps:
+                module, function = pps.rsplit(".", 1)
+                getattr(__import__(module, fromlist=[""]), function)(_d_instance)
+
             _d_instance.save()
             return _d_instance.object
         return plugin

djangocms_transfer/helpers.py

@@ -1,6 +1,7 @@
 from collections import defaultdict
 
 from django.core import serializers
+from django.conf import settings
 
 from . import get_serializer_name
 from .utils import get_plugin_fields, get_plugin_model
@@ -53,4 +54,10 @@ def get_plugin_data(plugin, only_meta=False):
         'parent_id': plugin.parent_id,
         'data': custom_data,
     }
-    return plugin_data
+
+    gpd = getattr(settings, "DJANGOCMS_TRANSFER_PROCESS_EXPORT_PLUGIN_DATA", None)
+    if gpd:
+        module, function = gpd.rsplit(".", 1)
+        return getattr(__import__(module, fromlist=[""]), function)(plugin, plugin_data)
+    else:
+        return plugin_data

djangocms_transfer/importer.py

@@ -20,6 +20,11 @@ def import_plugins(plugins, placeholder, language, root_plugin_id=None):
     tree_order = placeholder.get_plugin_tree_order(language, parent_id=root_plugin_id)
 
     for archived_plugin in plugins:
+        # custom handling via "get_plugin_data" can lead to "null"-values
+        # instead of plugin-dictionaries. We skip those here.
+        if archived_plugin is None:
+            continue
+
         if archived_plugin.parent_id:
             parent = source_map[archived_plugin.parent_id]
         else: