Fleshing out serializer fields

1 files changed, 72 insertions, 0 deletions

diff --git a/rest_framework/utils/representation.py b/rest_framework/utils/representation.py
new file mode 100644
index 00000000..1de21597
--- /dev/null
+++ b/rest_framework/utils/representation.py
@@ -0,0 +1,72 @@
+"""
+Helper functions for creating user-friendly representations
+of serializer classes and serializer fields.
+"""
+import re
+
+
+def smart_repr(value):
+    value = repr(value)
+
+    # Representations like u'help text'
+    # should simply be presented as 'help text'
+    if value.startswith("u'") and value.endswith("'"):
+        return value[1:]
+
+    # Representations like
+    # <django.core.validators.RegexValidator object at 0x1047af050>
+    # Should be presented as
+    # <django.core.validators.RegexValidator object>
+    value = re.sub(' at 0x[0-9a-f]{8,10}>', '>', value)
+
+    return value
+
+
+def field_repr(field, force_many=False):
+    kwargs = field._kwargs
+    if force_many:
+        kwargs = kwargs.copy()
+        kwargs['many'] = True
+        kwargs.pop('child', None)
+
+    arg_string = ', '.join([smart_repr(val) for val in field._args])
+    kwarg_string = ', '.join([
+        '%s=%s' % (key, smart_repr(val))
+        for key, val in sorted(kwargs.items())
+    ])
+    if arg_string and kwarg_string:
+        arg_string += ', '
+
+    if force_many:
+        class_name = force_many.__class__.__name__
+    else:
+        class_name = field.__class__.__name__
+
+    return "%s(%s%s)" % (class_name, arg_string, kwarg_string)
+
+
+def serializer_repr(serializer, indent, force_many=None):
+    ret = field_repr(serializer, force_many) + ':'
+    indent_str = '    ' * indent
+
+    if force_many:
+        fields = force_many.fields
+    else:
+        fields = serializer.fields
+
+    for field_name, field in fields.items():
+        ret += '\n' + indent_str + field_name + ' = '
+        if hasattr(field, 'fields'):
+            ret += serializer_repr(field, indent + 1)
+        elif hasattr(field, 'child'):
+            ret += list_repr(field, indent + 1)
+        else:
+            ret += field_repr(field)
+    return ret
+
+
+def list_repr(serializer, indent):
+    child = serializer.child
+    if hasattr(child, 'fields'):
+        return serializer_repr(serializer, indent, force_many=child)
+    return field_repr(serializer)