feat(tenancy): harden shared cloud runtime boundaries

src/langbot/pkg/persistence/databases/postgresql.py

@@ -1,8 +1,10 @@
 from __future__ import annotations
 
+import sqlalchemy
 import sqlalchemy.ext.asyncio as sqlalchemy_asyncio
 
 from .. import database
+from ..postgresql_url import normalize_asyncpg_url
 
 
 @database.manager_class('postgresql')
@@ -10,12 +12,29 @@ class PostgreSQLDatabaseManager(database.BaseDatabaseManager):
     """PostgreSQL database manager"""
 
     async def initialize(self) -> None:
-        postgresql_config = self.ap.instance_config.data.get('database', {}).get('postgresql', {})
-
-        host = postgresql_config.get('host', '127.0.0.1')
-        port = postgresql_config.get('port', 5432)
-        user = postgresql_config.get('user', 'postgres')
-        password = postgresql_config.get('password', 'postgres')
-        database = postgresql_config.get('database', 'postgres')
-        engine_url = f'postgresql+asyncpg://{user}:{password}@{host}:{port}/{database}'
+        if self.url_override is not None:
+            engine_url = self.url_override
+        else:
+            postgresql_config = self.ap.instance_config.data.get('database', {}).get('postgresql', {})
+            explicit_url = postgresql_config.get('url')
+            if explicit_url:
+                if not isinstance(explicit_url, str):
+                    raise ValueError('database.postgresql.url must be a string')
+                try:
+                    engine_url = sqlalchemy.engine.make_url(explicit_url)
+                except Exception:
+                    raise ValueError('database.postgresql.url is invalid') from None
+                try:
+                    engine_url = normalize_asyncpg_url(engine_url)
+                except ValueError:
+                    raise ValueError('database.postgresql.url must use valid PostgreSQL asyncpg options') from None
+            else:
+                engine_url = sqlalchemy.URL.create(
+                    'postgresql+asyncpg',
+                    username=postgresql_config.get('user', 'postgres'),
+                    password=postgresql_config.get('password', 'postgres'),
+                    host=postgresql_config.get('host', '127.0.0.1'),
+                    port=postgresql_config.get('port', 5432),
+                    database=postgresql_config.get('database', 'postgres'),
+                )
         self.engine = sqlalchemy_asyncio.create_async_engine(engine_url)