refactor: ConfigReader

Signed-off-by: Paulo Vital <[email protected]>

Author: pvital

src/instana/util/config_reader.py

@@ -1,22 +1,27 @@
 # (c) Copyright IBM Corp. 2025
 
-from typing import Union
-from instana.log import logger
 import yaml
 
+from instana.log import logger
+
 
 class ConfigReader:
-    def __init__(self, file_path: Union[str]) -> None:
+    def __init__(self, file_path: str) -> None:
         self.file_path = file_path
-        self.data = None
-        self.load_file()
+        self.data = {}
+        if file_path:
+            self.load_file()
+        else:
+            logger.warning("ConfigReader: No configuration file specified")
 
     def load_file(self) -> None:
         """Loads and parses the YAML file"""
         try:
             with open(self.file_path, "r") as file:
                 self.data = yaml.safe_load(file)
         except FileNotFoundError:
-            logger.error(f"Configuration file has not found: {self.file_path}")
+            logger.error(
+                f"ConfigReader: Configuration file has not found: {self.file_path}"
+            )
         except yaml.YAMLError as e:
-            logger.error(f"Error parsing YAML file: {e}")
+            logger.error(f"ConfigReader: Error parsing YAML file: {e}")

tests/util/test_config_reader.py

@@ -2,19 +2,77 @@
 
 import logging
 import os
+from typing import TYPE_CHECKING, Generator
 
 import pytest
+from yaml import YAMLError
 
 from instana.util.config import (
     get_disable_trace_configurations_from_yaml,
     parse_ignored_endpoints_from_yaml,
 )
+from instana.util.config_reader import ConfigReader
+
+if TYPE_CHECKING:
+    from pytest import LogCaptureFixture
+    from pytest_mock import MockerFixture
 
 
 class TestConfigReader:
-    def test_load_configuration_with_tracing(
-        self, caplog: pytest.LogCaptureFixture
+    @pytest.fixture(autouse=True)
+    def _resource(
+        self,
+        caplog: "LogCaptureFixture",
+    ) -> Generator[None, None, None]:
+        yield
+        caplog.clear()
+        if "INSTANA_CONFIG_PATH" in os.environ:
+            os.environ.pop("INSTANA_CONFIG_PATH")
+
+    def test_config_reader_null(self, caplog: "LogCaptureFixture") -> None:
+        config_reader = ConfigReader(os.environ.get("INSTANA_CONFIG_PATH", ""))
+        assert config_reader.file_path == ""
+        assert config_reader.data == {}
+        assert "ConfigReader: No configuration file specified" in caplog.messages
+
+    def test_config_reader_default(self) -> None:
+        filename = "tests/util/test_configuration-1.yaml"
+        os.environ["INSTANA_CONFIG_PATH"] = filename
+        config_reader = ConfigReader(os.environ.get("INSTANA_CONFIG_PATH", ""))
+        assert config_reader.file_path == filename
+        assert "tracing" in config_reader.data
+        assert len(config_reader.data["tracing"]) == 2
+
+    def test_config_reader_file_not_found_error(
+        self, caplog: "LogCaptureFixture"
     ) -> None:
+        filename = "tests/util/test_configuration-3.yaml"
+        os.environ["INSTANA_CONFIG_PATH"] = filename
+        config_reader = ConfigReader(os.environ.get("INSTANA_CONFIG_PATH", ""))
+        assert config_reader.file_path == filename
+        assert config_reader.data == {}
+        assert (
+            f"ConfigReader: Configuration file has not found: {filename}"
+            in caplog.messages
+        )
+
+    def test_config_reader_yaml_error(
+        self, caplog: "LogCaptureFixture", mocker: "MockerFixture"
+    ) -> None:
+        filename = "tests/util/test_configuration-1.yaml"
+        exception_message = "BLAH"
+        mocker.patch(
+            "instana.util.config_reader.yaml.safe_load",
+            side_effect=YAMLError(exception_message),
+        )
+
+        config_reader = ConfigReader(filename)  # noqa: F841
+        assert (
+            f"ConfigReader: Error parsing YAML file: {exception_message}"
+            in caplog.messages
+        )
+
+    def test_load_configuration_with_tracing(self, caplog: "LogCaptureFixture") -> None:
         caplog.set_level(logging.DEBUG, logger="instana")
 
         ignore_endpoints = parse_ignored_endpoints_from_yaml(
@@ -49,7 +107,7 @@ def test_load_configuration_with_tracing(
             not in caplog.messages
         )
 
-    def test_load_configuration_legacy(self, caplog: pytest.LogCaptureFixture) -> None:
+    def test_load_configuration_legacy(self, caplog: "LogCaptureFixture") -> None:
         caplog.set_level(logging.DEBUG, logger="instana")
 
         ignore_endpoints = parse_ignored_endpoints_from_yaml(