From be4f02335fb35d40a763d07b2d4e880b90083e53 Mon Sep 17 00:00:00 2001
From: Simon Willison <swillison@gmail.com>
Date: Thu, 1 Feb 2024 15:33:33 -0800
Subject: [PATCH] Treat plugins in metadata as if they were in config, closes
 #2248

---
 datasette/app.py            |  6 +++++
 datasette/utils/__init__.py | 40 +++++++++++++++++++++++++++++
 tests/test_plugins.py       | 51 +++++++++++++++++++++++++++++++++++++
 3 files changed, 97 insertions(+)

diff --git a/datasette/app.py b/datasette/app.py
index 0143223a..634283ff 100644
--- a/datasette/app.py
+++ b/datasette/app.py
@@ -74,6 +74,7 @@ from .utils import (
     find_spatialite,
     format_bytes,
     module_from_path,
+    move_plugins,
     parse_metadata,
     resolve_env_secrets,
     resolve_routes,
@@ -341,6 +342,11 @@ class Datasette:
             with config_files[0].open() as fp:
                 config = parse_metadata(fp.read())
 
+        # Move any "plugins" settings from metadata to config - updates them in place
+        metadata = metadata or {}
+        config = config or {}
+        move_plugins(metadata, config)
+
         self._metadata_local = metadata or {}
         self.sqlite_extensions = []
         for extension in sqlite_extensions or []:
diff --git a/datasette/utils/__init__.py b/datasette/utils/__init__.py
index 75f1c2f4..cc175b01 100644
--- a/datasette/utils/__init__.py
+++ b/datasette/utils/__init__.py
@@ -1287,3 +1287,43 @@ def make_slot_function(name, datasette, request, **kwargs):
         return markupsafe.Markup("".join(html_bits))
 
     return inner
+
+
+def move_plugins(source, destination):
+    """
+    Move 'plugins' keys from source to destination dictionary. Creates hierarchy in destination if needed.
+    After moving, recursively remove any keys in the source that are left empty.
+    """
+
+    def recursive_move(src, dest, path=None):
+        if path is None:
+            path = []
+        for key, value in list(src.items()):
+            new_path = path + [key]
+            if key == "plugins":
+                # Navigate and create the hierarchy in destination if needed
+                d = dest
+                for step in path:
+                    d = d.setdefault(step, {})
+                # Move the plugins
+                d[key] = value
+                # Remove the plugins from source
+                src.pop(key, None)
+            elif isinstance(value, dict):
+                recursive_move(value, dest, new_path)
+                # After moving, check if the current dictionary is empty and remove it if so
+                if not value:
+                    src.pop(key, None)
+
+    def prune_empty_dicts(d):
+        """
+        Recursively prune all empty dictionaries from a given dictionary.
+        """
+        for key, value in list(d.items()):
+            if isinstance(value, dict):
+                prune_empty_dicts(value)
+                if value == {}:
+                    d.pop(key, None)
+
+    recursive_move(source, destination)
+    prune_empty_dicts(source)
diff --git a/tests/test_plugins.py b/tests/test_plugins.py
index f26e3652..a53fc118 100644
--- a/tests/test_plugins.py
+++ b/tests/test_plugins.py
@@ -1458,3 +1458,54 @@ async def test_hook_register_events():
     datasette = Datasette(memory=True)
     await datasette.invoke_startup()
     assert any(k.__name__ == "OneEvent" for k in datasette.event_classes)
+
+
+@pytest.mark.parametrize(
+    "metadata,config,expected_metadata,expected_config",
+    (
+        (
+            # Instance level
+            {"plugins": {"datasette-foo": "bar"}},
+            {},
+            {},
+            {"plugins": {"datasette-foo": "bar"}},
+        ),
+        (
+            # Database level
+            {"databases": {"foo": {"plugins": {"datasette-foo": "bar"}}}},
+            {},
+            {},
+            {"databases": {"foo": {"plugins": {"datasette-foo": "bar"}}}},
+        ),
+        (
+            # Table level
+            {
+                "databases": {
+                    "foo": {"tables": {"bar": {"plugins": {"datasette-foo": "bar"}}}}
+                }
+            },
+            {},
+            {},
+            {
+                "databases": {
+                    "foo": {"tables": {"bar": {"plugins": {"datasette-foo": "bar"}}}}
+                }
+            },
+        ),
+        (
+            # Keep other keys
+            {"plugins": {"datasette-foo": "bar"}, "other": "key"},
+            {"original_config": "original"},
+            {"other": "key"},
+            {"original_config": "original", "plugins": {"datasette-foo": "bar"}},
+        ),
+    ),
+)
+def test_metadata_plugin_config_treated_as_config(
+    metadata, config, expected_metadata, expected_config
+):
+    ds = Datasette(metadata=metadata, config=config)
+    actual_metadata = ds.metadata()
+    assert "plugins" not in actual_metadata
+    assert actual_metadata == expected_metadata
+    assert ds.config == expected_config