Fix package_version_utils.py logic (#689)

* Fix package_version_utils.py logic

Co-authored-by: Timothy Pansino <[email protected]>
Co-authored-by: Hannah Stepanek <[email protected]>
Co-authored-by: Uma Annamalai <[email protected]>

* Move description of func into func itself

* typecast lists into tuples

* Remove breakpoints

* Empty _test_package_version_utils.py

* Make changes to the test

Co-authored-by: Timothy Pansino <[email protected]>
Co-authored-by: Hannah Stepanek <[email protected]>
Co-authored-by: Uma Annamalai <[email protected]>

newrelic/common/package_version_utils.py

@@ -14,10 +14,57 @@
 
 import sys
 
+# Need to account for 4 possible variations of version declaration specified in (rejected) PEP 396
+VERSION_ATTRS = ("__version__", "version", "__version_tuple__", "version_tuple")  # nosec
+NULL_VERSIONS = frozenset((None, "", "0", "0.0", "0.0.0", "0.0.0.0", (0,), (0, 0), (0, 0, 0), (0, 0, 0, 0)))  # nosec
+
 
 def get_package_version(name):
-    # importlib was introduced into the standard library starting in Python3.8.
-    if "importlib" in sys.modules and hasattr(sys.modules["importlib"], "metadata"):
-        return sys.modules["importlib"].metadata.version(name)  # pylint: disable=E1101
-    elif "pkg_resources" in sys.modules:
-        return sys.modules["pkg_resources"].get_distribution(name).version
+    """Gets the version of the library.
+    :param name: The name of library.
+    :type name: str
+    :return: The version of the library. Returns None if can't determine version.
+    :type return: str or None
+
+    Usage::
+        >>> get_package_version("botocore")
+                "1.1.0"
+    """
+
+    def _get_package_version(name):
+        module = sys.modules.get(name, None)
+        version = None
+        for attr in VERSION_ATTRS:
+            try:
+                version = getattr(module, attr, None)
+                # Cast any version specified as a list into a tuple.
+                version = tuple(version) if isinstance(version, list) else version
+                if version not in NULL_VERSIONS:
+                    return version
+            except Exception:
+                pass
+
+        # importlib was introduced into the standard library starting in Python3.8.
+        if "importlib" in sys.modules and hasattr(sys.modules["importlib"], "metadata"):
+            try:
+                version = sys.modules["importlib"].metadata.version(name)  # pylint: disable=E1101
+                if version not in NULL_VERSIONS:
+                    return version
+            except Exception:
+                pass
+
+        if "pkg_resources" in sys.modules:
+            try:
+                version = sys.modules["pkg_resources"].get_distribution(name).version
+                if version not in NULL_VERSIONS:
+                    return version
+            except Exception:
+                pass
+
+    version = _get_package_version(name)
+
+    # Coerce iterables into a string
+    if isinstance(version, tuple):
+        version = ".".join(str(v) for v in version)
+
+    return version

tests/agent_unittests/test_package_version_utils.py

@@ -0,0 +1,71 @@
+# Copyright 2010 New Relic, Inc.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#      http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+import sys
+
+import pytest
+from testing_support.validators.validate_function_called import validate_function_called
+
+from newrelic.common.package_version_utils import (
+    NULL_VERSIONS,
+    VERSION_ATTRS,
+    get_package_version,
+)
+
+IS_PY38_PLUS = sys.version_info[:2] >= (3, 8)
+SKIP_IF_NOT_IMPORTLIB_METADATA = pytest.mark.skipif(not IS_PY38_PLUS, reason="importlib.metadata is not supported.")
+SKIP_IF_IMPORTLIB_METADATA = pytest.mark.skipif(
+    IS_PY38_PLUS, reason="importlib.metadata is preferred over pkg_resources."
+)
+
+
+@pytest.fixture(scope="function", autouse=True)
+def patched_pytest_module(monkeypatch):
+    for attr in VERSION_ATTRS:
+        if hasattr(pytest, attr):
+            monkeypatch.delattr(pytest, attr)
+
+    yield pytest
+
+
+@pytest.mark.parametrize(
+    "attr,value,expected_value",
+    (
+        ("version", "1.2.3.4", "1.2.3.4"),
+        ("__version__", "1.3.5rc2", "1.3.5rc2"),
+        ("__version_tuple__", (3, 5, 8), "3.5.8"),
+        ("version_tuple", [3, 1, "0b2"], "3.1.0b2"),
+    ),
+)
+def test_get_package_version(attr, value, expected_value):
+    # There is no file/module here, so we monkeypatch
+    # pytest instead for our purposes
+    setattr(pytest, attr, value)
+    version = get_package_version("pytest")
+    assert version == expected_value
+    delattr(pytest, attr)
+
+
+@SKIP_IF_NOT_IMPORTLIB_METADATA
+@validate_function_called("importlib.metadata", "version")
+def test_importlib_metadata():
+    version = get_package_version("pytest")
+    assert version not in NULL_VERSIONS, version
+
+
+@SKIP_IF_IMPORTLIB_METADATA
+@validate_function_called("pkg_resources", "get_distribution")
+def test_pkg_resources_metadata():
+    version = get_package_version("pytest")
+    assert version not in NULL_VERSIONS, version