feat: add skip_reason to Plugin; improve PluginLoader init messaging

tests/test_plugin.py

@@ -0,0 +1,83 @@
+import asyncio
+import logging
+import textwrap
+
+from hbd.client.plugin import Plugin, PluginLoader, PluginRegistry
+
+
+def test_plugin_skip_reason_defaults_none(tmp_path):
+    plugin_code = textwrap.dedent("""
+        from hbd.client.plugin import MonitorPlugin
+
+        class MinimalPlugin(MonitorPlugin):
+            name = "minimal"
+            version = "1.0.0"
+            interval = 60
+
+            async def initialize(self):
+                return True
+
+            async def _collect_metrics(self):
+                return {}
+    """)
+    (tmp_path / "minimal.py").write_text(plugin_code)
+    registry = PluginRegistry()
+    loader = PluginLoader(registry)
+    asyncio.run(loader.load_from_directory(tmp_path))
+    plugin = registry.get("minimal")
+    assert plugin is not None
+    assert plugin.skip_reason is None
+
+
+def test_loader_logs_info_when_skip_reason_set(tmp_path, caplog):
+    plugin_code = textwrap.dedent("""
+        from hbd.client.plugin import MonitorPlugin
+
+        class SkippablePlugin(MonitorPlugin):
+            name = "skippable"
+            version = "1.0.0"
+            interval = 60
+
+            async def initialize(self):
+                self.skip_reason = "not configured in yaml"
+                return False
+
+            async def _collect_metrics(self):
+                return {}
+    """)
+    (tmp_path / "skippable.py").write_text(plugin_code)
+    registry = PluginRegistry()
+    loader = PluginLoader(registry)
+
+    with caplog.at_level(logging.INFO, logger="plugin.loader"):
+        count = asyncio.run(loader.load_from_directory(tmp_path))
+
+    assert count == 0
+    assert any("skipped: not configured in yaml" in r.message for r in caplog.records)
+    assert not any("failed initialization" in r.message for r in caplog.records)
+
+
+def test_loader_logs_warning_when_no_skip_reason(tmp_path, caplog):
+    plugin_code = textwrap.dedent("""
+        from hbd.client.plugin import MonitorPlugin
+
+        class FailPlugin(MonitorPlugin):
+            name = "fail"
+            version = "1.0.0"
+            interval = 60
+
+            async def initialize(self):
+                return False
+
+            async def _collect_metrics(self):
+                return {}
+    """)
+    (tmp_path / "fail_plugin.py").write_text(plugin_code)
+    registry = PluginRegistry()
+    loader = PluginLoader(registry)
+
+    with caplog.at_level(logging.WARNING, logger="plugin.loader"):
+        count = asyncio.run(loader.load_from_directory(tmp_path))
+
+    assert count == 0
+    assert any("failed initialization" in r.message for r in caplog.records)