Set kwargs_to_list to force str/unicode to str when nested in a dic…

…t or list.

Closes cameronmaske#11

celery_once/helpers.py

@@ -34,6 +34,22 @@ def now_unix():
     return int(time())
 
 
+def force_string(kwargs):
+    """
+    Force key in dict or list to a string.
+    Fixes: https://github.com/TrackMaven/celery-once/issues/11
+    """
+    if isinstance(kwargs, dict):
+        return {
+            force_string(key): force_string(value) for key, value in six.iteritems(kwargs)}
+    elif isinstance(kwargs, list):
+        return [force_string(element) for element in kwargs]
+    elif isinstance(kwargs, str) or isinstance(kwargs, unicode):
+        return str(kwargs)
+    else:
+        return kwargs
+
+
 def kwargs_to_list(kwargs):
     """
     Turns {'a': 1, 'b': 2} into ["a-1", "b-2"]
@@ -42,7 +58,7 @@ def kwargs_to_list(kwargs):
     # Kwargs are sorted in alphabetic order.
     # Taken from http://www.saltycrane.com/blog/2007/09/how-to-sort-python-dictionary-by-keys/
     for k, v in sorted(six.iteritems(kwargs), key=lambda kv: (str(kv[0]), str(kv[1]))):
-        kwargs_list.append(str(k) + '-' + str(v))
+        kwargs_list.append(str(k) + '-' + str(force_string(v)))
     return kwargs_list
 
 

tests/unit/test_helpers.py

@@ -27,6 +27,12 @@ def test_kwargs_to_list_4():
     assert keys == ["boolean-True", "int-1", "list-[1, '2']", "str-abc"]
 
 
+def test_kwargs_to_list_5():
+    keys = kwargs_to_list(
+        {'a': {u'b': 'c'}, 'list': [u'a', 'b'], u'zzz': 1})
+    assert keys == ["a-{'b': 'c'}", "list-['a', 'b']", "zzz-1"]
+
+
 def test_queue_once_key():
     key = queue_once_key("example", {})
     assert key == "qo_example"
@@ -40,4 +46,3 @@ def test_queue_once_key_kwargs():
 def test_queue_once_key_kwargs_restrict_keys():
     key = queue_once_key("example", {'pk': 10, 'id': 10}, restrict_to=['pk'])
     assert key == "qo_example_pk-10"
-