apply processors to chained exceptions (#604)

Author: beniwohli

CHANGELOG.md

@@ -1,5 +1,12 @@
 # Changelog
 
+## Unreleased
+[Check the diff](https://github.com/elastic/apm-agent-python/compare/v5.2.0...master)
+
+### Bugfixes
+ * fixed an issue with DroppedSpans and logging integration (#602)
+ * fixed an issue with processors not being applied to chained exceptions (#604)
+
 ## v5.2.0
 [Check the diff](https://github.com/elastic/apm-agent-python/compare/v5.1.2...v5.2.0)
 

elasticapm/processors.py

@@ -283,6 +283,13 @@ def _process_stack_frames(event, func):
     if "exception" in event and "stacktrace" in event["exception"]:
         for frame in event["exception"]["stacktrace"]:
             func(frame)
+        # check for chained exceptions
+        cause = event["exception"].get("cause", None)
+        while cause:
+            if "stacktrace" in cause[0]:
+                for frame in cause[0]["stacktrace"]:
+                    func(frame)
+            cause = cause[0].get("cause", None)
     if "log" in event and "stacktrace" in event["log"]:
         for frame in event["log"]["stacktrace"]:
             func(frame)

tests/processors/tests.py

@@ -88,26 +88,51 @@ def test_stacktrace():
         "exception": {
             "stacktrace": [
                 {"vars": {"foo": "bar", "password": "hello", "the_secret": "hello", "a_password_here": "hello"}}
-            ]
+            ],
+            "cause": [
+                {
+                    "stacktrace": [
+                        {"vars": {"foo": "bar", "password": "hello", "the_secret": "hello", "a_password_here": "hello"}}
+                    ],
+                    "cause": [
+                        {
+                            "stacktrace": [
+                                {
+                                    "vars": {
+                                        "foo": "bar",
+                                        "password": "hello",
+                                        "the_secret": "hello",
+                                        "a_password_here": "hello",
+                                    }
+                                }
+                            ]
+                        }
+                    ],
+                }
+            ],
         }
     }
 
     result = processors.sanitize_stacktrace_locals(None, data)
 
     assert "stacktrace" in result["exception"]
-    stack = result["exception"]["stacktrace"]
-    assert len(stack) == 1
-    frame = stack[0]
-    assert "vars" in frame
-    vars = frame["vars"]
-    assert "foo" in vars
-    assert vars["foo"] == "bar"
-    assert "password" in vars
-    assert vars["password"] == processors.MASK
-    assert "the_secret" in vars
-    assert vars["the_secret"] == processors.MASK
-    assert "a_password_here" in vars
-    assert vars["a_password_here"] == processors.MASK
+    for stacktrace in (
+        result["exception"]["stacktrace"],
+        result["exception"]["cause"][0]["stacktrace"],
+        result["exception"]["cause"][0]["cause"][0]["stacktrace"],
+    ):
+        assert len(stacktrace) == 1
+        frame = stacktrace[0]
+        assert "vars" in frame
+        vars = frame["vars"]
+        assert "foo" in vars
+        assert vars["foo"] == "bar"
+        assert "password" in vars
+        assert vars["password"] == processors.MASK
+        assert "the_secret" in vars
+        assert vars["the_secret"] == processors.MASK
+        assert "a_password_here" in vars
+        assert vars["a_password_here"] == processors.MASK
 
 
 def test_remove_http_request_body(http_test_data):