avoid return-value warning when the runtime version is not python3.7 (#263)

* avoid return-value warning when the runtime version is not python3.7

Co-authored-by: CircleCI <[email protected]>

Author: saartochner-lumigo

.pre-commit-config.yaml

@@ -19,13 +19,15 @@ repos:
     hooks:
     -   id: flake8
         args: ["--ignore","E501,W503","--exclude","src/lumigo_tracer/libs/*"]
+        additional_dependencies: ['importlib-metadata==4.13.0']
 
 -   repo: https://github.com/PyCQA/bandit
     rev: '1.7.0'
     hooks:
     -   id: bandit
         exclude: ^src/test/
         args: ["-lll"]
+        additional_dependencies: ['importlib-metadata==4.13.0']
 
 -   repo: https://github.com/Yelp/detect-secrets
     rev: v1.2.0

.secrets.baseline

@@ -184,7 +184,7 @@
         "filename": "src/test/unit/test_lumigo_utils.py",
         "hashed_secret": "f32b67c7e26342af42efabc674d441dca0a281c5",
         "is_verified": false,
-        "line_number": 262
+        "line_number": 263
       }
     ],
     "src/test/unit/test_tracer.py": [
@@ -193,21 +193,21 @@
         "filename": "src/test/unit/test_tracer.py",
         "hashed_secret": "9b55630d152a6501889a2378eb53fe4b260fb91f",
         "is_verified": false,
-        "line_number": 58
+        "line_number": 60
       },
       {
         "type": "Secret Keyword",
         "filename": "src/test/unit/test_tracer.py",
         "hashed_secret": "f13de0da12f8375756b1bc56b248cc8e62e0c302",
         "is_verified": false,
-        "line_number": 395
+        "line_number": 397
       },
       {
         "type": "Secret Keyword",
         "filename": "src/test/unit/test_tracer.py",
         "hashed_secret": "dabe695c9892b5cb937379817679c0fb0be6a3df",
         "is_verified": false,
-        "line_number": 478
+        "line_number": 502
       }
     ],
     "src/test/unit/wrappers/http/test_http_parser.py": [
@@ -220,5 +220,5 @@
       }
     ]
   },
-  "generated_at": "2022-09-01T11:44:39Z"
+  "generated_at": "2022-10-12T08:37:22Z"
 }

src/lumigo_tracer/lumigo_utils.py

@@ -844,6 +844,10 @@ def get_stacktrace(exception: Exception) -> str:
     return "".join(filter(lambda line: STACKTRACE_LINE_TO_DROP not in line, original_traceback))
 
 
+def is_python_37() -> bool:
+    return os.environ.get("AWS_EXECUTION_ENV") == "AWS_Lambda_python3.7"
+
+
 try:
     # Try to establish the connection in initialization
     if (

src/lumigo_tracer/spans_container.py

@@ -26,6 +26,7 @@
     should_use_tracer_extension,
     MANUAL_TRACES_KEY,
     lumigo_safe_execute,
+    is_python_37,
 )
 from lumigo_tracer import lumigo_utils
 from lumigo_tracer.event.event_dumper import EventDumper
@@ -292,13 +293,18 @@ def end(self, ret_val=None, event: Optional[dict] = None, context=None) -> Optio
                 if ret_val is not None:
                     parsed_ret_val = lumigo_dumps(ret_val, enforce_jsonify=True, decimal_safe=True)
             except Exception as err:
-                suffix = ""
-                if err.args:
-                    suffix = f'Original message: "{err.args[0]}"'
-                self.function_span["error"] = self._create_exception_event(
-                    "ReturnValueError",
-                    "The lambda will probably fail due to bad return value. " + suffix,
-                )
+                if is_python_37():
+                    suffix = ""
+                    if err.args:
+                        suffix = f'Original message: "{err.args[0]}"'
+                    self.function_span["error"] = self._create_exception_event(
+                        "ReturnValueError",
+                        "The lambda will probably fail due to bad return value. " + suffix,
+                    )
+                else:
+                    get_logger().exception(
+                        "Could not serialize the return value of the lambda", exc_info=True
+                    )
         self.function_span.update({"return_value": parsed_ret_val})
         if _is_span_has_error(self.function_span):
             self._set_error_extra_data(event)

src/test/unit/test_lumigo_utils.py

@@ -51,6 +51,7 @@
     TRUNCATE_SUFFIX,
     DEFAULT_AUTO_TAG_KEY,
     lumigo_safe_execute,
+    is_python_37,
 )
 import json
 
@@ -686,3 +687,20 @@ def test_lumigo_safe_execute_with_level(severity, caplog):
     with lumigo_safe_execute("test", severity=severity):
         raise ValueError("Failing")
     assert caplog.records[-1].levelno == severity
+
+
+@pytest.mark.parametrize(
+    "env_value, expected",
+    [
+        ("AWS_Lambda_python3.8", False),
+        ("AWS_Lambda_python3.7", True),
+    ],
+)
+def test_is_python_37(monkeypatch, env_value, expected):
+    monkeypatch.setenv("AWS_EXECUTION_ENV", env_value)
+    assert is_python_37() == expected
+
+
+def test_is_python_37_without_env(monkeypatch):
+    monkeypatch.delenv("AWS_EXECUTION_ENV", raising=False)
+    assert is_python_37() is False

src/test/unit/test_tracer.py

@@ -1,3 +1,5 @@
+import logging
+
 import datetime
 import json
 import re
@@ -453,7 +455,9 @@ def lambda_test_function(event, context):
     assert enrichment_spans[0][EXECUTION_TAGS_KEY] == [{"key": key, "value": "my_value"}]
 
 
-def test_not_jsonable_return(monkeypatch, context):
+def test_not_jsonable_return_value_python37(monkeypatch, context):
+    monkeypatch.setenv("AWS_EXECUTION_ENV", "AWS_Lambda_python3.7")
+
     @lumigo_tracer()
     def lambda_test_function(event, context):
         return {"a": datetime.datetime.now()}
@@ -468,6 +472,26 @@ def lambda_test_function(event, context):
     assert function_span["error"]["message"] == expected_message
 
 
+def test_not_jsonable_return_value_non_python37(monkeypatch, context, caplog):
+    monkeypatch.setenv("AWS_EXECUTION_ENV", "AWS_Lambda_python3.8")
+
+    @lumigo_tracer()
+    def lambda_test_function(event, context):
+        return {"a": datetime.datetime.now()}
+
+    lambda_test_function({}, context)
+
+    function_span = SpansContainer.get_span().function_span
+    assert function_span["return_value"] is None
+    assert "error" not in function_span
+    assert next(
+        log
+        for log in caplog.records
+        if log.levelno == logging.ERROR
+        and "Could not serialize the return value of the lambda" in log.message
+    )
+
+
 @mock_kinesis
 def test_china(context, reporter_mock, monkeypatch):
     china_region_for_test = "ap-east-1"  # Moto doesn't work for China