Improve RelatedField and callable default handling

- callable default values will now be properly called 
  - PrimaryKeyRelatedField and SlugRelatedField will now return an appropriate type based on the relation model's Field
  - mock views now have a request object bound even when public is True

testproj/articles/migrations/0001_initial.py

@@ -1,6 +1,8 @@
-# Generated by Django 2.0 on 2017-12-05 04:05
+# Generated by Django 2.0 on 2017-12-23 09:07
 
+from django.conf import settings
 from django.db import migrations, models
+import django.db.models.deletion
 
 
 class Migration(migrations.Migration):
@@ -8,6 +10,7 @@ class Migration(migrations.Migration):
     initial = True
 
     dependencies = [
+        migrations.swappable_dependency(settings.AUTH_USER_MODEL),
     ]
 
     operations = [
@@ -15,12 +18,13 @@ class Migration(migrations.Migration):
             name='Article',
             fields=[
                 ('id', models.AutoField(auto_created=True, primary_key=True, serialize=False, verbose_name='ID')),
-                ('title', models.CharField(help_text='Main article headline', max_length=255, unique=True)),
-                ('body', models.TextField(help_text='Article content', max_length=5000)),
-                ('slug', models.SlugField(blank=True, help_text='Unique URL slug identifying the article', unique=True)),
+                ('title', models.CharField(help_text='title model help_text', max_length=255, unique=True)),
+                ('body', models.TextField(help_text='article model help_text', max_length=5000)),
+                ('slug', models.SlugField(blank=True, help_text='slug model help_text', unique=True)),
                 ('date_created', models.DateTimeField(auto_now_add=True)),
                 ('date_modified', models.DateTimeField(auto_now=True)),
                 ('cover', models.ImageField(blank=True, upload_to='article/original/')),
+                ('author', models.ForeignKey(on_delete=django.db.models.deletion.CASCADE, related_name='articles', to=settings.AUTH_USER_MODEL)),
             ],
         ),
     ]

testproj/articles/migrations/0002_auto_20171221_1635.py

@@ -1,28 +0,0 @@
-# Generated by Django 2.0 on 2017-12-21 15:35
-
-from django.db import migrations, models
-
-
-class Migration(migrations.Migration):
-
-    dependencies = [
-        ('articles', '0001_initial'),
-    ]
-
-    operations = [
-        migrations.AlterField(
-            model_name='article',
-            name='body',
-            field=models.TextField(help_text='article model help_text', max_length=5000),
-        ),
-        migrations.AlterField(
-            model_name='article',
-            name='slug',
-            field=models.SlugField(blank=True, help_text='slug model help_text', unique=True),
-        ),
-        migrations.AlterField(
-            model_name='article',
-            name='title',
-            field=models.CharField(help_text='title model help_text', max_length=255, unique=True),
-        ),
-    ]

testproj/articles/models.py

@@ -7,5 +7,6 @@ class Article(models.Model):
     slug = models.SlugField(help_text="slug model help_text", unique=True, blank=True)
     date_created = models.DateTimeField(auto_now_add=True)
     date_modified = models.DateTimeField(auto_now=True)
+    author = models.ForeignKey('auth.User', related_name='articles', on_delete=models.CASCADE)
 
     cover = models.ImageField(upload_to='article/original/', blank=True)

testproj/articles/serializers.py

@@ -14,12 +14,19 @@ class ArticleSerializer(serializers.ModelSerializer):
 
     class Meta:
         model = Article
-        fields = ('title', 'body', 'slug', 'date_created', 'date_modified',
+        fields = ('title', 'author', 'body', 'slug', 'date_created', 'date_modified',
                   'references', 'uuid', 'cover', 'cover_name')
         read_only_fields = ('date_created', 'date_modified',
                             'references', 'uuid', 'cover_name')
         lookup_field = 'slug'
-        extra_kwargs = {'body': {'help_text': 'body serializer help_text'}}
+        extra_kwargs = {
+            'body': {'help_text': 'body serializer help_text'},
+            'author': {
+                'default': serializers.CurrentUserDefault(),
+                'help_text': "The ID of the user that created this article; if none is provided, "
+                             "defaults to the currently logged in user."
+            },
+        }
 
 
 class ImageUploadSerializer(serializers.Serializer):

testproj/articles/views.py

@@ -20,6 +20,11 @@ class NoPagingAutoSchema(SwaggerAutoSchema):
         return False
 
 
+class ArticlePagination(LimitOffsetPagination):
+    default_limit = 5
+    max_limit = 25
+
+
 @method_decorator(name='list', decorator=swagger_auto_schema(
     operation_description="description from swagger_auto_schema via method_decorator"
 ))
@@ -41,8 +46,7 @@ class ArticleViewSet(viewsets.ModelViewSet):
     lookup_value_regex = r'[a-z0-9]+(?:-[a-z0-9]+)'
     serializer_class = serializers.ArticleSerializer
 
-    pagination_class = LimitOffsetPagination
-    max_page_size = 5
+    pagination_class = ArticlePagination
     filter_backends = (DjangoFilterBackend, OrderingFilter)
     filter_fields = ('title',)
     ordering_fields = ('date_modified','date_created')