Fix merging dicts for duplicate dotted keys

CHANGELOG.md

@@ -1,5 +1,9 @@
 # Changelog
 
+## Unreleased
+
+* Fix for duplicate dotted keys ([#46])
+
 ## 1.0.0 (2021-02-08)
 
 * Remove "beta" designation

ecs_logging/_structlog.py

@@ -36,7 +36,7 @@ def __call__(self, _, name, event_dict):
 
     def format_to_ecs(self, event_dict):
         # type: (Dict[str, Any]) -> Dict[str, Any]
-        event_dict["message"] = event_dict.pop("event")
+        event_dict["message"] = str(event_dict.pop("event"))
         if "@timestamp" not in event_dict:
             event_dict["@timestamp"] = (
                 datetime.datetime.utcfromtimestamp(time.time()).strftime(

ecs_logging/_utils.py

@@ -111,8 +111,8 @@ def merge_dicts(from_, into):
     When called has side-effects within 'destination'.
     """
     for key, value in from_.items():
-        if isinstance(value, dict):
-            merge_dicts(value, into.setdefault(key, {}))
+        if isinstance(value, dict) and isinstance(into.setdefault(key, {}), dict):
+            merge_dicts(value, into[key])
         else:
             into[key] = value
     return into

tests/conftest.py

@@ -19,6 +19,7 @@
 import json
 import os
 import collections
+import sys
 
 import pytest
 
@@ -27,6 +28,10 @@ class ValidationError(Exception):
     pass
 
 
+if sys.version_info[0] >= 3:
+    basestring = str
+
+
 @pytest.fixture
 def spec_validator():
     with open(

tests/test_structlog_formatter.py

@@ -22,7 +22,12 @@
 
 
 def make_event_dict():
-    return {"event": "test message", "log.logger": "logger-name"}
+    return {
+        "event": "test message",
+        "log.logger": "logger-name",
+        "foo": "bar",
+        "foo.dataset": "baz",
+    }
 
 
 @mock.patch("time.time")
@@ -33,6 +38,7 @@ def test_event_dict_formatted(time, spec_validator):
     assert spec_validator(formatter(None, "debug", make_event_dict())) == (
         '{"@timestamp":"2020-03-20T16:16:37.187Z","log.level":"debug",'
         '"message":"test message","ecs":{"version":"1.6.0"},'
+        '"foo":{"dataset":"baz"},'
         '"log":{"logger":"logger-name"}}'
     )