Raise a warning if multiple plugins exist with same name

CHANGELOG.md

@@ -10,6 +10,8 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - [#337](https://github.com/equinor/webviz-config/pull/337) - New generic plugin to
 generate a [Pivot table](https://en.wikipedia.org/wiki/Pivot_table) based on
 [Dash Pivottable](https://github.com/plotly/dash-pivottable).
+- [#333](https://github.com/equinor/webviz-config/pull/333) - Warning is now raised
+if more than one plugin project provides a plugin with the same name.
 
 ## [0.2.2] - 2020-11-16
 

tests/test_plugin_init.py

@@ -0,0 +1,60 @@
+import warnings
+
+import mock
+
+from webviz_config.plugins._utils import load_webviz_plugins_with_metadata
+
+
+class DistMock:
+    # pylint: disable=too-few-public-methods
+    def __init__(self, entry_points, name):
+        self.metadata = {"name": name}
+
+        self.entry_points = entry_points
+        self.version = "123"
+
+
+plugin_entrypoint_mock1 = mock.Mock()
+plugin_entrypoint_mock1.group = "webviz_config_plugins"
+plugin_entrypoint_mock1.name = "SomePlugin1"
+
+plugin_entrypoint_mock2 = mock.Mock()
+plugin_entrypoint_mock2.group = "webviz_config_plugins"
+plugin_entrypoint_mock2.name = "SomePlugin2"
+
+dist_mock1 = DistMock([plugin_entrypoint_mock1], "dist_mock1")
+dist_mock2 = DistMock([plugin_entrypoint_mock1], "dist_mock2")
+dist_mock3 = DistMock([plugin_entrypoint_mock2], "dist_mock3")
+
+
+def test_no_warning():
+    globals_mock = {}
+    with warnings.catch_warnings(record=True) as warn:
+        metadata = load_webviz_plugins_with_metadata(
+            [dist_mock1, dist_mock3], globals_mock
+        )
+        assert len(warn) == 0, "Too many warnings"
+
+    assert len(metadata) == 2, "Wrong number of items in metadata"
+    assert "SomePlugin1" in globals_mock
+    assert "SomePlugin2" in globals_mock
+
+
+def test_warning_multiple():
+    globals_mock = {}
+    with warnings.catch_warnings(record=True) as warn:
+        metadata = load_webviz_plugins_with_metadata(
+            [dist_mock1, dist_mock2], globals_mock
+        )
+
+        assert len(warn) == 1
+        assert issubclass(warn[-1].category, RuntimeWarning)
+        assert str(warn[-1].message) == (
+            "Multiple versions of plugin with name SomePlugin1. "
+            "Already loaded from project dist_mock1. "
+            "Overwriting using plugin with from project dist_mock2"
+        )
+
+    assert len(metadata) == 1, "Wrong number of items in metadata"
+    assert metadata["SomePlugin1"]["dist_name"] == "dist_mock2", "Wrong dist name"
+    assert "SomePlugin1" in globals_mock

webviz_config/plugins/__init__.py

@@ -2,45 +2,16 @@
 the utility itself.
 """
 
-import inspect
 from typing import Optional
 
 try:
     # Python 3.8+
-    # pylint: disable=ungrouped-imports
     from importlib.metadata import distributions  # type: ignore
-    from typing import TypedDict  # type: ignore
 except ModuleNotFoundError:
     # Python < 3.8
     from importlib_metadata import distributions  # type: ignore
-    from typing_extensions import TypedDict  # type: ignore
 
+from ._utils import load_webviz_plugins_with_metadata, PluginDistInfo
 
-class PluginDistInfo(TypedDict):
-    dist_name: str
-    dist_version: str
-    documentation_url: Optional[str]
-    download_url: Optional[str]
-    issue_url: Optional[str]
 
-
-metadata = {}
-
-for dist in distributions():
-    for entry_point in dist.entry_points:
-        if entry_point.group == "webviz_config_plugins":
-            project_urls = {
-                value.split(",")[0]: value.split(",")[1].strip()
-                for (key, value) in dist.metadata.items()
-                if key == "Project-URL"
-            }
-
-            metadata[entry_point.name] = {
-                "dist_name": dist.metadata["name"],
-                "dist_version": dist.version,
-                "documentation_url": project_urls.get("Documentation"),
-                "download_url": project_urls.get("Download"),
-                "tracker_url": project_urls.get("Tracker"),
-            }
-
-            globals()[entry_point.name] = entry_point.load()
+metadata = load_webviz_plugins_with_metadata(distributions(), globals())

webviz_config/plugins/_utils.py

@@ -0,0 +1,59 @@
+import warnings
+from typing import Any, Dict, Iterable, Optional
+
+try:
+    # Python 3.8+
+    # pylint: disable=ungrouped-imports
+    from typing import TypedDict  # type: ignore
+except ImportError:
+    # Python < 3.8
+    from typing_extensions import TypedDict  # type: ignore
+
+
+class PluginDistInfo(TypedDict):
+    dist_name: str
+    dist_version: str
+    documentation_url: Optional[str]
+    download_url: Optional[str]
+    tracker_url: Optional[str]
+
+
+def load_webviz_plugins_with_metadata(
+    distributions: Iterable, loaded_plugins: Dict[str, Any]
+) -> Dict[str, PluginDistInfo]:
+    """Loads the given distributions, finds entry points corresponding to webviz-config
+    plugins, and put them into the mutable input dictionary loaded_plugins
+    (key is plugin name string, value is reference to plugin class).
+    Also returns a dictionary of plugin metadata.
+    """
+
+    metadata: Dict[str, PluginDistInfo] = {}
+
+    for dist in distributions:
+        for entry_point in dist.entry_points:
+            if entry_point.group == "webviz_config_plugins":
+                project_urls = {
+                    value.split(",")[0]: value.split(",")[1].strip()
+                    for (key, value) in dist.metadata.items()
+                    if key == "Project-URL"
+                }
+
+                if entry_point.name in metadata:
+                    warnings.warn(
+                        f"Multiple versions of plugin with name {entry_point.name}. "
+                        f"Already loaded from project {metadata[entry_point.name]['dist_name']}. "
+                        f"Overwriting using plugin with from project {dist.metadata['name']}",
+                        RuntimeWarning,
+                    )
+
+                metadata[entry_point.name] = {
+                    "dist_name": dist.metadata["name"],
+                    "dist_version": dist.version,
+                    "documentation_url": project_urls.get("Documentation"),
+                    "download_url": project_urls.get("Download"),
+                    "tracker_url": project_urls.get("Tracker"),
+                }
+
+                loaded_plugins[entry_point.name] = entry_point.load()
+
+    return metadata