fix(backup): restore finds plugin tables by path, as the app loads them (#5674)

Run 9075: the restore got through schema and data, then all_metadata's
`import plugins` failed in the image, where plugins/ is a directory the app
loads by path (PLUGIN_DIRS), not an installed package. It now loads each
plugin under the loader's own module name from the bootstrap's plugin
dirs, which `steward restore` passes. A plugin whose models are already
mapped under either name is skipped rather than mapped twice.

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

steward/backup/restore.py

@@ -36,26 +36,32 @@ class Restored:
     fixed: int                 # rows put right between data and constraints
 
 
-def all_metadata() -> MetaData:
-    """Steward's tables, every bundled plugin's included, without an app:
-    the restore runs before anything else would load them."""
+def all_metadata(plugin_dirs: list[Path] | None = None) -> MetaData:
+    """Steward's tables, every plugin's included, without an app: the
+    restore runs before anything else would load them. Plugins are found in
+    `plugin_dirs` (the bootstrap's, bundled first) and loaded by path under
+    the same module names the app gives them, so a plugin the app already
+    loaded isn't mapped twice. Without dirs: the repository's plugins/."""
     import importlib
-    import pkgutil
-
     import sys
 
-    import plugins
+    import steward
     import steward.models  # noqa: F401 — registers core tables
+    from steward.core.plugin_manager import _import_plugin, resolve_plugin_path
     from steward.models.base import Base
-    for info in pkgutil.iter_modules(plugins.__path__):
-        # A plugin the app already loaded is under the loader's name; its
-        # models imported a second time would map every table twice.
-        loaded = f"_steward_plugin_{info.name}"
-        package = loaded if loaded in sys.modules else f"plugins.{info.name}"
+
+    roots = [Path(d).resolve() for d in (plugin_dirs or [Path(steward.__file__).parent.parent / "plugins"])]
+    names = sorted({p.name for root in roots if root.is_dir() for p in root.iterdir()
+                    if (p / "__init__.py").exists() and (p / "models.py").exists()})
+    for name in names:
+        if f"plugins.{name}.models" in sys.modules or f"_steward_plugin_{name}.models" in sys.modules:
+            continue          # already mapped, under one name or the other
+        path = resolve_plugin_path(roots, name)
         try:
-            importlib.import_module(f"{package}.models")
-        except ImportError:       # no models, or an optional dependency missing
-            continue
+            package = _import_plugin(name, path)
+            importlib.import_module(f"{package.__name__}.models")
+        except Exception:     # a plugin that won't load: its tables are left as pg_restore put them
+            logger.warning("Restore: couldn't load plugin %r's tables", name, exc_info=True)
     return Base.metadata
 
 
@@ -167,7 +173,7 @@ async def _execute(database_url: str, statements: list[str]) -> int:
 
 
 async def restore(path: Path, database_url: str, *, wipe: bool = False,
-                  metadata: MetaData | None = None) -> Restored:
+                  metadata: MetaData | None = None, plugin_dirs: list[Path] | None = None) -> Restored:
     """Restore a backup file into the database at `database_url`. It must be
     empty unless `wipe`, which drops everything in its public schema first."""
     existing = await _tables(database_url)
@@ -182,6 +188,6 @@ async def restore(path: Path, database_url: str, *, wipe: bool = False,
         info, dump, key = await asyncio.to_thread(read_backup, path, Path(tmp))
         await _pg_restore(database_url, dump, "pre-data")
         await _pg_restore(database_url, dump, "data")
-        fixed = await _execute(database_url, dangling_fixes(metadata or all_metadata()))
+        fixed = await _execute(database_url, dangling_fixes(metadata or all_metadata(plugin_dirs)))
         await _pg_restore(database_url, dump, "post-data")
     return Restored(info, key, fixed)

steward/cli.py

@@ -96,7 +96,8 @@ def restore_command(ctx: click.Context, backup_file: Path, wipe: bool) -> None:
 
     boot = load_bootstrap(Path(ctx.obj["config"]))
     try:
-        done = asyncio.run(restore(backup_file, boot["database_url"], wipe=wipe))
+        done = asyncio.run(restore(backup_file, boot["database_url"], wipe=wipe,
+                                   plugin_dirs=[Path(d) for d in boot["plugin_dirs"]]))
     except BackupError as exc:
         raise click.ClickException(str(exc)) from None
     made = done.manifest.get("created_at", "?")