more tests for tagging serializer

utils/tag_serializers.py

@@ -1,4 +1,11 @@
+import traceback
+
 from rest_framework import serializers
+from rest_framework.fields import CharField, ListField
+from rest_framework.serializers import raise_errors_on_nested_writes
+from rest_framework.utils import model_meta
+
+from tagulous.models.descriptors import FakeTagRelatedManager
 
 from taggit_serializer.serializers import TagListSerializerField, TaggitSerializer
 
@@ -40,14 +47,67 @@ class SingleTagSerializerField(serializers.Field):
         return value
 
 
-class CustomTagSerializer(serializers.Serializer):
+class CustomTagSerializer(serializers.ModelSerializer):
+    """
+    Differentiate between tags and single-tags
+    """
+
+    def __init__(self, instance=None, data='', **kwargs):
+        self.serializer_field_mapping[SingleTagSerializerField] = CharField
+        self.serializer_field_mapping[TagListSerializerField] = ListField
+        super(CustomTagSerializer, self).__init__(instance, data, **kwargs)
 
     def create(self, validated_data):
         to_be_tagged, validated_data = self._pop_tags(validated_data)
 
-        tag_object = super(CustomTagSerializer, self).create(validated_data)
+        # tag_object = super(CustomTagSerializer, self).create(validated_data)
+        raise_errors_on_nested_writes('create', self, validated_data)
 
-        return self._save_tags(tag_object, to_be_tagged)
+        ModelClass = self.Meta.model
+
+        # Remove many-to-many relationships from validated_data.
+        # They are not valid arguments to the default `.create()` method,
+        # as they require that the instance has already been saved.
+        info = model_meta.get_field_info(ModelClass)
+        many_to_many = {}
+        for field_name, relation_info in info.relations.items():
+            if relation_info.to_many and (field_name in validated_data):
+                many_to_many[field_name] = validated_data.pop(field_name)
+
+        try:
+            instance = ModelClass._default_manager.create(**validated_data)
+        except TypeError:
+            tb = traceback.format_exc()
+            msg = (
+                'Got a `TypeError` when calling `%s.%s.create()`. '
+                'This may be because you have a writable field on the '
+                'serializer class that is not a valid argument to '
+                '`%s.%s.create()`. You may need to make the field '
+                'read-only, or override the %s.create() method to handle '
+                'this correctly.\nOriginal exception was:\n %s' %
+                (
+                    ModelClass.__name__,
+                    ModelClass._default_manager.name,
+                    ModelClass.__name__,
+                    ModelClass._default_manager.name,
+                    self.__class__.__name__,
+                    tb
+                )
+            )
+            raise TypeError(msg)
+
+        # Save many-to-many relationships after the instance is created.
+        if many_to_many:
+            for field_name, value in many_to_many.items():
+                field = getattr(instance, field_name)
+                import ipdb; ipdb.set_trace()
+                if type(field) == "<class 'tagulous.models.descriptors.TagRelatedManager'>":
+                    for item in value:
+                        field.set(item)
+                else:
+                    field.set(value)
+
+        return self._save_tags(instance, to_be_tagged)
 
     def update(self, instance, validated_data):
         to_be_tagged, validated_data = self._pop_tags(validated_data)
@@ -66,12 +126,10 @@ class CustomTagSerializer(serializers.Serializer):
 
     def _pop_tags(self, validated_data):
         to_be_tagged = {}
-        import ipdb; ipdb.set_trace()
-        for key in self.fields.keys():
-            field = self.fields[key]
+        for key in self.serializer_field_mapping.keys():
+            field = self.serializer_field_mapping[key]
             if isinstance(field, TagListSerializerField):
                 if key in validated_data:
                     to_be_tagged[key] = validated_data.pop(key)
 
         return (to_be_tagged, validated_data)
-