feat: Read plugin version from distribution, with fallback to package

singer_sdk/helpers/_compat.py

@@ -1,4 +1,7 @@
 """Compatibility helpers."""
+from __future__ import annotations
+
+import pathlib
 
 try:
     from typing import final
@@ -12,4 +15,31 @@
     # Running on pre-3.8 Python; use importlib-metadata package
     import importlib_metadata as metadata  # type: ignore
 
-__all__ = ["metadata", "final"]
+
+# Future: replace with `importlib.metadata.packages_distributions()` introduced in 3.10
+def get_project_distribution(file_path=None) -> metadata.Distribution | None:
+    """Get project distribution.
+
+    This walks each distribution on `sys.path` looking for one whose installed paths
+    include the given path.
+
+    Args:
+        file_path: File path to find distribution for.
+
+    Returns:
+        A discovered Distribution or None.
+    """
+    for dist in metadata.distributions():
+        try:
+            relative = pathlib.Path(file_path or __file__).relative_to(
+                dist.locate_file("")
+            )
+        except ValueError:
+            pass
+        else:
+            if dist.files and relative in dist.files:
+                return dist
+    return None
+
+
+__all__ = ["metadata", "get_project_distribution", "final"]

singer_sdk/plugin_base.py

@@ -27,7 +27,7 @@
 from singer_sdk.configuration._dict_config import parse_environment_config
 from singer_sdk.exceptions import ConfigValidationError
 from singer_sdk.helpers._classproperty import classproperty
-from singer_sdk.helpers._compat import metadata
+from singer_sdk.helpers._compat import get_project_distribution, metadata
 from singer_sdk.helpers._secrets import SecretString, is_common_secret_key
 from singer_sdk.helpers._util import read_json_file
 from singer_sdk.helpers.capabilities import (
@@ -162,10 +162,14 @@ def plugin_version(cls) -> str:
         Returns:
             The package version number.
         """
-        try:
-            version = metadata.version(cls.name)
-        except metadata.PackageNotFoundError:
-            version = "[could not be detected]"
+        distribution = get_project_distribution(__file__)
+        if distribution:
+            version = str(distribution.metadata["Version"])
+        else:
+            try:
+                version = metadata.version(cls.name)
+            except metadata.PackageNotFoundError:
+                version = "[could not be detected]"
         return version
 
     @classproperty

tests/core/test_helpers.py

@@ -0,0 +1,26 @@
+import platform
+import site
+from pathlib import Path
+
+import pytest
+
+from singer_sdk.helpers._compat import get_project_distribution, metadata
+
+
+def test_get_project_distribution():
+    """Test `get_project_distribution()`.
+
+    click is a representative example of a distributed package from our dependency tree.
+    Any similar singer_sdk dependency could be used in stead.
+    """
+    if platform.system() == "Windows":
+        pytest.xfail("Doesn't pass on windows.")
+
+    site_package_paths = site.getsitepackages()
+    site_package_path = next(
+        pth for pth in site_package_paths if Path(pth).parts[-1] == "site-packages"
+    )
+    singer_sdk_dependency_path = Path(site_package_path) / "click" / "__init__.py"
+    discovered_dst = get_project_distribution(singer_sdk_dependency_path)
+    assert discovered_dst
+    assert discovered_dst.name == "click"