From decbdc534644384c18a603dc35650b044d0b5a0a Mon Sep 17 00:00:00 2001
From: Ismael Carnales <icarnales@gmail.com>
Date: Mon, 24 Aug 2009 17:16:18 -0300
Subject: [PATCH] added DjangoItem item class

---
 scrapy/contrib_exp/djangoitem.py         | 37 ++++++++++++++++
 scrapy/item.py                           |  9 ++--
 scrapy/tests/test_djangoitem/__init__.py | 56 ++++++++++++++++++++++++
 scrapy/tests/test_djangoitem/models.py   | 10 +++++
 scrapy/tests/test_djangoitem/settings.py |  2 +
 5 files changed, 111 insertions(+), 3 deletions(-)
 create mode 100644 scrapy/contrib_exp/djangoitem.py
 create mode 100644 scrapy/tests/test_djangoitem/__init__.py
 create mode 100644 scrapy/tests/test_djangoitem/models.py
 create mode 100644 scrapy/tests/test_djangoitem/settings.py

diff --git a/scrapy/contrib_exp/djangoitem.py b/scrapy/contrib_exp/djangoitem.py
new file mode 100644
index 000000000..22a23af14
--- /dev/null
+++ b/scrapy/contrib_exp/djangoitem.py
@@ -0,0 +1,37 @@
+from scrapy.item import DictItem, Field
+
+
+class DjangoItemMeta(type):
+
+    def  __new__(mcs, class_name, bases, attrs):
+        cls = super(DjangoItemMeta, mcs).__new__(mcs, class_name, bases, attrs)
+        cls.fields = cls.fields.copy()
+
+        if cls.django_model:
+            cls._model_fields = []
+            cls._model_meta = cls.django_model._meta
+            for model_field in cls._model_meta.fields:
+                # XXX: for now we're treating each PK as autogenerated field
+                if model_field != cls._model_meta.pk:
+                    cls.fields[model_field.name] = Field()
+                    cls._model_fields.append(model_field.name)
+            # add declared fields
+            for n, v in attrs.iteritems():
+                if isinstance(v, Field):
+                    cls.fields[n] = v
+        return cls
+
+
+class DjangoItem(DictItem):
+
+    __metaclass__ = DjangoItemMeta
+
+    django_model = None
+
+    def save(self, commit=True):
+        modelargs = dict((f, self.get(f, None)) for f in self._model_fields)
+        model = self.django_model(**modelargs)
+        if commit:
+            model.save()
+        return model
+
diff --git a/scrapy/item.py b/scrapy/item.py
index 20f52d72d..f51ac35db 100644
--- a/scrapy/item.py
+++ b/scrapy/item.py
@@ -34,9 +34,7 @@ class _ItemMeta(type):
         return cls
 
 
-class Item(DictMixin, BaseItem):
-
-    __metaclass__ = _ItemMeta
+class DictItem(DictMixin, BaseItem):
 
     fields = {}
 
@@ -81,6 +79,11 @@ class Item(DictMixin, BaseItem):
         return "%s(%s)" % (self.__class__.__name__, values)
 
 
+class Item(DictItem):
+
+    __metaclass__ = _ItemMeta
+
+
 class ScrapedItem(BaseItem):
 
     def __init__(self, data=None):
diff --git a/scrapy/tests/test_djangoitem/__init__.py b/scrapy/tests/test_djangoitem/__init__.py
new file mode 100644
index 000000000..7a0a3ca8f
--- /dev/null
+++ b/scrapy/tests/test_djangoitem/__init__.py
@@ -0,0 +1,56 @@
+import os
+from twisted.trial import unittest
+
+from scrapy.contrib_exp.djangoitem import DjangoItem, Field
+
+os.environ['DJANGO_SETTINGS_MODULE'] = 'scrapy.tests.test_djangoitem.settings'
+
+try:
+    from models import Person
+    django = True
+except ImportError:
+    django = False
+
+
+class BasePersonItem(DjangoItem):
+    django_model = Person
+
+
+class NewFieldPersonItem(BasePersonItem):
+    other = Field()
+
+
+class OverrideFieldPersonItem(BasePersonItem):
+    age = Field(default=1)
+
+
+class DjangoItemTest(TestCase):
+    
+    def setUp(
+        if not django:
+            raise unittest.SkipTest("Django is not available")
+
+    def test_base(self):
+        i = BasePersonItem()
+        self.assertEqual(i.fields.keys(), ['age', 'name'])
+
+    def test_new_fields(self):
+        i = NewFieldPersonItem()
+        self.assertEqual(i.fields.keys(), ['age', 'other', 'name'])
+
+    def test_override_field(self):
+        i = OverrideFieldPersonItem()
+        self.assertEqual(i.fields.keys(), ['age', 'name'])
+        self.assertEqual(i.fields['age'], {'default': 1})
+
+    def test_save(self):
+        i = BasePersonItem()
+        self.assertEqual(i.fields.keys(), ['age', 'name'])
+
+        i['name'] = 'John'
+        i['age'] = '22'
+        person = i.save(commit=False)
+
+        self.assertEqual(person.name, 'John')
+        self.assertEqual(person.age, '22')
+
diff --git a/scrapy/tests/test_djangoitem/models.py b/scrapy/tests/test_djangoitem/models.py
new file mode 100644
index 000000000..57a8d648d
--- /dev/null
+++ b/scrapy/tests/test_djangoitem/models.py
@@ -0,0 +1,10 @@
+from django.db import models
+
+
+class Person(models.Model):
+    name = models.CharField(max_length=255)
+    age = models.IntegerField()
+
+    class Meta:
+        app_label = 'test_djangoitem'
+
diff --git a/scrapy/tests/test_djangoitem/settings.py b/scrapy/tests/test_djangoitem/settings.py
new file mode 100644
index 000000000..6ece9ee7a
--- /dev/null
+++ b/scrapy/tests/test_djangoitem/settings.py
@@ -0,0 +1,2 @@
+DATABASE_ENGINE = 'sqlite3'
+DATABASE_NAME = ':memory:'