feat: add system health diagnostics

backend/app/system_health/application.py

@@ -0,0 +1,42 @@
+"""Startup-cached, non-secret application metadata."""
+
+from dataclasses import dataclass
+from pathlib import Path
+
+from alembic.config import Config
+from alembic.script import ScriptDirectory
+
+from app.config import settings
+
+
+def _clean_build_value(value: str | None) -> str | None:
+    if value is None:
+        return None
+    cleaned = value.strip()
+    return cleaned[:128] if cleaned else None
+
+
+def _expected_migration_head() -> str | None:
+    try:
+        backend_root = Path(__file__).resolve().parents[2]
+        config = Config(str(backend_root / "alembic.ini"))
+        config.set_main_option("script_location", str(backend_root / "alembic"))
+        return ScriptDirectory.from_config(config).get_current_head()
+    except Exception:
+        return None
+
+
+@dataclass(frozen=True)
+class ApplicationMetadata:
+    environment: str
+    build_commit: str | None
+    build_version: str | None
+    expected_migration_head: str | None
+
+
+APPLICATION_METADATA = ApplicationMetadata(
+    environment=settings.app_env,
+    build_commit=_clean_build_value(settings.minerops_build_commit),
+    build_version=_clean_build_value(settings.minerops_build_version),
+    expected_migration_head=_expected_migration_head(),
+)