fix(dogpile.cache): parse argument from both args and kwargs (#2734) (#2739)

* Add regression test case

The issue is easily reproduced when only providing kwargs to
get_or_create.

* fix(dogpile.cache): use get_argument_value for extracting args

* Add words

Co-authored-by: Nicolas Vivet <[email protected]>
(cherry picked from commit bcbe3a3)

Co-authored-by: Kyle Verhoog <[email protected]>

Author: mergify[bot]

ddtrace/contrib/dogpile_cache/region.py

@@ -4,14 +4,15 @@
 
 from ...constants import SPAN_MEASURED_KEY
 from ...pin import Pin
+from ...utils import get_argument_value
 
 
 def _wrap_get_create(func, instance, args, kwargs):
     pin = Pin.get_from(dogpile.cache)
     if not pin or not pin.enabled():
         return func(*args, **kwargs)
 
-    key = args[0]
+    key = get_argument_value(args, kwargs, 0, "key")
     with pin.tracer.trace("dogpile.cache", resource="get_or_create", span_type=SpanTypes.CACHE) as span:
         span.set_tag(SPAN_MEASURED_KEY)
         span.set_tag("key", key)
@@ -25,7 +26,7 @@ def _wrap_get_create_multi(func, instance, args, kwargs):
     if not pin or not pin.enabled():
         return func(*args, **kwargs)
 
-    keys = args[0]
+    keys = get_argument_value(args, kwargs, 0, "keys")
     with pin.tracer.trace("dogpile.cache", resource="get_or_create_multi", span_type="cache") as span:
         span.set_tag(SPAN_MEASURED_KEY)
         span.set_tag("keys", keys)

docs/spelling_wordlist.txt

@@ -15,6 +15,7 @@ agentless
 analytics
 api
 app
+args
 asgi
 asyncio
 attrs
@@ -43,6 +44,7 @@ ddtrace
 deprecations
 django
 dogpile
+dogpile.cache
 dogstatsd
 elasticsearch
 elasticsearch1
@@ -70,6 +72,7 @@ js
 kombu
 kubernetes
 kwarg
+kwargs
 lifecycle
 lookups
 mako

releasenotes/notes/dogpile.cache-1d03e088872ca747.yaml

@@ -0,0 +1,5 @@
+---
+fixes:
+  - |
+    dogpile.cache: handle both kwargs and args in the wrapper functions (using
+      only kwargs would result in an IndexError.

tests/contrib/dogpile_cache/test_tracing.py

@@ -26,7 +26,7 @@ def region(tracer):
     patch()
     # Setup a simple dogpile cache region for testing.
     # The backend is trivial so we can use memory to simplify test setup.
-    test_region = dogpile.cache.make_region(name="TestRegion")
+    test_region = dogpile.cache.make_region(name="TestRegion", key_mangler=lambda x: x)
     test_region.configure("dogpile.cache.memory")
     Pin.override(dogpile.cache, tracer=tracer)
     return test_region
@@ -205,3 +205,12 @@ def test_calls_inner_functions_correctly(self, region, mocker):
         spy_multi_cache.reset_mock()
         assert [6, 10] == multi_cache(3, 5)
         assert spy_single_cache.call_count == 0
+
+
+def test_get_or_create_kwarg_only(region):
+    """
+    When get_or_create is called with only kwargs
+        The arguments should be handled correctly
+    """
+    assert region.get_or_create(key="key", creator=lambda: 3) == 3
+    assert region.get_or_create_multi(keys="keys", creator=lambda *args: [1, 2])