feat: add postgresql:// scheme as alias for asyncpg (#2154)

* feat: add postgresql:// scheme as alias for asyncpg

The official PostgreSQL documentation lists both postgres:// and postgresql://
as valid connection URIs. Previously only postgres:// worked; this adds
postgresql:// as a supported scheme alias.

Fixes #2147

* docs: add comment explaining the postgresql scheme alias

---------

Co-authored-by: Contributor <user@example.com>

Author: r266-tech

tests/backends/test_db_url.py

@@ -7,6 +7,7 @@
 
 _postgres_scheme_engines = {
     "postgres": "tortoise.backends.asyncpg",
+    "postgresql": "tortoise.backends.asyncpg",
     "asyncpg": "tortoise.backends.asyncpg",
     "psycopg": "tortoise.backends.psycopg",
 }

tortoise/backends/base/config_generator.py

@@ -9,6 +9,7 @@
 from tortoise.exceptions import ConfigurationError
 
 urlparse.uses_netloc.append("postgres")
+urlparse.uses_netloc.append("postgresql")
 urlparse.uses_netloc.append("asyncpg")
 urlparse.uses_netloc.append("psycopg")
 urlparse.uses_netloc.append("sqlite")
@@ -127,6 +128,8 @@
 }
 # Create an alias for backwards compatibility
 DB_LOOKUP["postgres"] = DB_LOOKUP["asyncpg"]
+# "postgresql" is the scheme accepted by libpq and pydantic's PostgresDsn
+DB_LOOKUP["postgresql"] = DB_LOOKUP["asyncpg"]
 
 
 def _quote_url_userinfo(db_url: str) -> str:
@@ -211,7 +214,7 @@ def expand_db_url(db_url: str, testing: bool = False) -> dict:
         # asyncpg accepts None for password, but aiomysql not
         params[vmap["password"]] = (
             None
-            if (not url.password and db_backend in {"postgres", "asyncpg", "psycopg"})
+            if (not url.password and db_backend in {"postgres", "postgresql", "asyncpg", "psycopg"})
             else urlparse.unquote(url.password or "")
         )