reorganize API

src/c3nav/api/serializers.py

@@ -0,0 +1,46 @@
+from collections import Iterable
+
+from django.db.models.manager import BaseManager
+from rest_framework import serializers
+
+
+class PkField(serializers.DictField):
+    """
+    give primary key
+    """
+    def to_representation(self, obj):
+        if hasattr(obj, 'pk'):
+            return obj.pk
+        elif isinstance(obj, Iterable):
+            return tuple(self.to_representation(elem) for elem in obj)
+        elif isinstance(obj, BaseManager):
+            return tuple(self.to_representation(elem) for elem in obj.all())
+        return None
+
+
+class RecursiveSerializerMixin(serializers.Serializer):
+    def __init__(self, *args, **kwargs):
+        super().__init__(*args, **kwargs)
+
+        request = self.context.get('request')
+        request_sparse = self.context['request_sparse'] = request is not None and request.GET.get('sparse')
+        sparse = self.context['sparse'] = request_sparse or self.context.get('sparse')
+
+        if sparse:
+            for name in getattr(self.Meta, 'sparse_exclude', ()):
+                value = self.fields.get(name)
+                if value is not None and isinstance(value, serializers.Serializer):
+                    self.fields[name] = PkField()
+
+            if request_sparse:
+                for name in tuple(self.fields):
+                    if name == 'url' or name.endswith('_url'):
+                        self.fields.pop(name)
+
+    def sparse_context(self):
+        return {'request': self.context.get('request'), 'sparse': True}
+
+    def recursive_value(self, serializer, obj, *args, **kwargs):
+        if self.context.get('sparse'):
+            return PkField().to_representation(obj)
+        return serializer(obj, *args, **kwargs, context=self.sparse_context()).data

src/c3nav/api/templates/rest_framework/api.html

@@ -29,5 +29,6 @@
 {% block description %}
 {% if breadcrumblist|length == 1 %}
 <p>Welcome to the c3nav RESTful API.</p>
+<p><small><em>Add <code>?sparse=1</code> to any request to flatten its result.</em></small></p>
 {% else %}{{ description }}{% endif %}
 {% endblock %}