fix(web): preserve dotted schema keys when saving plugin config (#370)

The plugin config form posts form-data with dot-notation paths
(e.g. "leagues.fifa.world.enabled"). _get_schema_property and
_set_nested_value split those paths on every dot, so a schema key that
itself contains a dot (soccer league keys like "fifa.world", "eng.1")
was mistaken for nested "fifa" -> "world" objects. Per-league edits
(enable, favorite_teams, nested booleans) were written to a fabricated
"leagues.fifa.world" branch while the real league object was never
updated, so saves silently dropped the change and produced a
byte-identical config.

Both helpers now greedily match the longest path segment that exists in
the schema (_get_schema_property) or the config being updated
(_set_nested_value), mirroring the frontend's dotted-key handling.

Adds regression tests covering schema lookup, value typing, and writes
under dotted league keys, plus a guard that plain nested paths still work.

Co-authored-by: Claude Opus 4.8 <noreply@anthropic.com>

test/web_interface/test_dotted_league_keys.py

@@ -0,0 +1,93 @@
+"""
+Regression test for saving plugin config fields whose schema keys contain dots
+(e.g. soccer league keys like "fifa.world", "eng.1", "usa.1").
+
+Bug: the web config form posts form-data with dotted paths such as
+"leagues.fifa.world.enabled". The helpers that resolve those paths split on every
+dot, so the dotted league key "fifa.world" was mistaken for nested "fifa" ->
+"world" objects. Per-league edits (enable, favorite_teams, nested booleans) were
+written to a fabricated "leagues.fifa.world" branch while the real league object
+was never updated, so the save silently dropped the change and the saved config
+came out byte-identical.
+"""
+
+import unittest
+
+from web_interface.blueprints.api_v3 import (
+    _get_schema_property,
+    _set_nested_value,
+    _parse_form_value_with_schema,
+)
+
+
+SCHEMA = {
+    "type": "object",
+    "properties": {
+        "leagues": {
+            "type": "object",
+            "properties": {
+                "fifa.world": {
+                    "type": "object",
+                    "properties": {
+                        "enabled": {"type": "boolean"},
+                        "favorite_teams": {
+                            "type": "array",
+                            "items": {"type": "string"},
+                        },
+                        "display_modes": {
+                            "type": "object",
+                            "properties": {"live": {"type": "boolean"}},
+                        },
+                    },
+                }
+            },
+        }
+    },
+}
+
+
+class TestDottedLeagueKeys(unittest.TestCase):
+    def test_schema_lookup_resolves_dotted_league_key(self):
+        prop = _get_schema_property(SCHEMA, "leagues.fifa.world.favorite_teams")
+        self.assertIsNotNone(prop, "dotted league key path should resolve")
+        self.assertEqual(prop.get("type"), "array")
+
+    def test_schema_lookup_resolves_nested_object_beneath_dotted_key(self):
+        live = _get_schema_property(SCHEMA, "leagues.fifa.world.display_modes.live")
+        self.assertIsNotNone(live)
+        self.assertEqual(live.get("type"), "boolean")
+
+    def test_parse_typed_value_for_dotted_key(self):
+        # Comma-separated text input "USA" must become an array, not the raw string.
+        parsed = _parse_form_value_with_schema(
+            "USA", "leagues.fifa.world.favorite_teams", SCHEMA
+        )
+        self.assertEqual(parsed, ["USA"])
+
+    def test_set_value_updates_real_league_not_fabricated_branch(self):
+        config = {"leagues": {"fifa.world": {"enabled": False, "favorite_teams": []}}}
+        _set_nested_value(config, "leagues.fifa.world.enabled", True)
+        _set_nested_value(config, "leagues.fifa.world.favorite_teams", ["USA"])
+
+        self.assertTrue(config["leagues"]["fifa.world"]["enabled"])
+        self.assertEqual(config["leagues"]["fifa.world"]["favorite_teams"], ["USA"])
+        # The real league must be updated and no fabricated "fifa" branch created.
+        self.assertNotIn("fifa", config["leagues"])
+
+    def test_set_value_into_missing_leaf_lands_in_real_league(self):
+        # A leaf that does not exist yet still resolves into the real dotted league.
+        config = {"leagues": {"fifa.world": {"enabled": False}}}
+        _set_nested_value(config, "leagues.fifa.world.display_modes.live", True)
+        self.assertTrue(
+            config["leagues"]["fifa.world"]["display_modes"]["live"]
+        )
+        self.assertNotIn("fifa", config["leagues"])
+
+    def test_plain_nested_paths_still_work(self):
+        config = {}
+        _set_nested_value(config, "customization.text.font", "small")
+        self.assertEqual(config["customization"]["text"]["font"], "small")
+
+
+if __name__ == "__main__":
+    unittest.main()

web_interface/blueprints/api_v3.py

@@ -3558,21 +3558,29 @@ def _get_schema_property(schema, key_path):
 
     parts = key_path.split('.')
     current = schema['properties']
+    i = 0
 
-    for i, part in enumerate(parts):
+    while i < len(parts):
-        if part not in current:
+        # Try progressively longer candidates, longest first, so schema keys that
-            return None
+        # themselves contain dots (e.g. league keys like "fifa.world") are matched
-
+        # instead of being mistaken for nested "fifa" -> "world" objects.
-        prop = current[part]
+        matched = False
-
+        for j in range(len(parts), i, -1):
-        # If this is the last part, return the property
+            candidate = '.'.join(parts[i:j])
-        if i == len(parts) - 1:
+            if isinstance(current, dict) and candidate in current:
-            return prop
+                prop = current[candidate]
-
+                # Consumed all remaining parts — this is the target property.
-        # If this is an object with properties, navigate deeper
+                if j == len(parts):
-        if isinstance(prop, dict) and 'properties' in prop:
+                    return prop
-            current = prop['properties']
+                # Navigate deeper through an object with properties.
-        else:
+                if isinstance(prop, dict) and 'properties' in prop:
+                    current = prop['properties']
+                    i = j
+                    matched = True
+                    break
+                # Matched a non-object before consuming the path — can't go deeper.
+                return None
+        if not matched:
             return None
 
     return None
@@ -3745,10 +3753,45 @@ def _parse_form_value_with_schema(value, key_path, schema):
     return value
 
 
+def _resolve_key_segments(key_path, config):
+    """Split a dot-notation path into segments, greedily preserving keys that
+    themselves contain dots (e.g. league keys like "fifa.world").
+
+    At each level the longest candidate that matches a key already present in the
+    config wins; otherwise the path splits on the next dot (the normal
+    nested-create case). Because dotted keys such as ``leagues."fifa.world"``
+    always exist in the saved config being updated, this routes the value to the
+    real league object instead of fabricating a ``leagues.fifa.world`` tree.
+    """
+    parts = key_path.split('.')
+    segments = []
+    node = config
+    i = 0
+    while i < len(parts):
+        matched = False
+        if isinstance(node, dict):
+            for j in range(len(parts), i, -1):
+                candidate = '.'.join(parts[i:j])
+                if candidate in node:
+                    segments.append(candidate)
+                    node = node[candidate]
+                    i = j
+                    matched = True
+                    break
+        if not matched:
+            part = parts[i]
+            segments.append(part)
+            node = node.get(part) if isinstance(node, dict) else None
+            i += 1
+    return segments
+
+
 def _set_nested_value(config, key_path, value):
     """
     Set a value in a nested dict using dot notation path.
     Handles existing nested dicts correctly by merging instead of replacing.
+    Keys containing dots (e.g. league keys like "fifa.world") are preserved when
+    they already exist in the config rather than being split into nested objects.
 
     Args:
         config: The config dict to modify
@@ -3758,22 +3801,22 @@ def _set_nested_value(config, key_path, value):
     # Skip setting if value is the sentinel
     if value is _SKIP_FIELD:
         return
-    
+
-    parts = key_path.split('.')
+    segments = _resolve_key_segments(key_path, config)
     current = config
 
     # Navigate/create intermediate dicts
-    for i, part in enumerate(parts[:-1]):
+    for seg in segments[:-1]:
-        if part not in current:
+        if seg not in current:
-            current[part] = {}
+            current[seg] = {}
-        elif not isinstance(current[part], dict):
+        elif not isinstance(current[seg], dict):
             # If the existing value is not a dict, replace it with a dict
-            current[part] = {}
+            current[seg] = {}
-        current = current[part]
+        current = current[seg]
 
     # Set the final value (don't overwrite with empty dict if value is None and we want to preserve structure)
-    if value is not None or parts[-1] not in current:
+    if value is not None or segments[-1] not in current:
-        current[parts[-1]] = value
+        current[segments[-1]] = value
 
 
 def _set_missing_booleans_to_false(config, schema_props, form_keys, prefix='', config_node=None):