fix(proxy): fail fast on non-PostgreSQL DATABASE_URL instead of hanging on startup (#30366)

* fix(proxy): fail fast on non-PostgreSQL DATABASE_URL instead of hanging on startup

LiteLLM's Prisma datasource is pinned to provider = 'postgresql', so a sqlite:// or mysql:// DATABASE_URL can never connect.

Today that surfaces as an opaque startup stall where the port never binds, and a separate 'DB not connected' 500 on /key/generate when no DATABASE_URL is set at all leaves operators guessing what to configure.

Validate the DATABASE_URL / DIRECT_URL scheme in run_server before any Prisma call and exit with an actionable message naming the unsupported scheme.

Also reword CommonProxyErrors.db_not_connected_error to tell the operator to set DATABASE_URL to a postgresql:// connection string.

Add regression tests covering postgres acceptance and sqlite/mysql/mssql rejection.

* fix: resolve CI failures and proxy DB URL typing issue

litellm/proxy/_types.py

@@ -3336,7 +3336,9 @@ class ProxyException(Exception):
 
 class CommonProxyErrors(str, enum.Enum):
     db_not_connected_error = (
-        "DB not connected. See https://docs.litellm.ai/docs/proxy/virtual_keys"
+        "DB not connected. This endpoint needs a database; set DATABASE_URL to a "
+        "PostgreSQL connection string (postgresql://...) to enable it. "
+        "See https://docs.litellm.ai/docs/proxy/virtual_keys"
     )
     no_llm_router = "No models configured on proxy"
     not_allowed_access = "Admin-only endpoint. Not allowed to access this."

litellm/proxy/db/db_url_settings.py

@@ -32,7 +32,7 @@ password when their ``*_READ_REPLICA`` counterpart is unset.
 
 import os
 import urllib.parse
-from typing import Optional, cast
+from typing import Final, Optional, cast
 
 from pydantic import AliasChoices, Field
 from pydantic_settings import BaseSettings, SettingsConfigDict
@@ -44,6 +44,41 @@ from litellm.proxy.auth import rds_iam_token
 _IAM_ENV_KEY = "IAM_TOKEN_DB_AUTH"
 _DEFAULT_PG_PORT = "5432"
 
+# schema.prisma pins `provider = "postgresql"`, so these are the only schemes
+# Prisma can actually connect with.
+SUPPORTED_DB_SCHEMES: Final[frozenset[str]] = frozenset({"postgresql", "postgres"})
+_MISSING_SCHEME = "<missing scheme>"
+
+
+def unsupported_db_scheme(database_url: str) -> Optional[str]:
+    """Return the connection URL scheme when it is not PostgreSQL, else None.
+
+    A `sqlite://` / `mysql://` URL can never connect against the
+    postgresql-only datasource, but the resulting Prisma failure is opaque and
+    version-dependent (a confusing migration error, or a startup that never
+    binds). Callers use this to reject the URL up front with an actionable
+    error instead.
+
+    A schemeless value (e.g. a malformed DSN like ``user:pass@host/db``) yields
+    the ``_MISSING_SCHEME`` placeholder rather than the raw URL, so callers that
+    log the return value never echo embedded credentials.
+    """
+    scheme = urllib.parse.urlsplit(database_url).scheme.lower()
+    if scheme in SUPPORTED_DB_SCHEMES:
+        return None
+    return scheme or _MISSING_SCHEME
+
+
+def unsupported_db_scheme_message(env_var: str, scheme: str) -> str:
+    """Operator-facing message naming the offending env var and scheme."""
+    return (
+        f"{env_var} uses unsupported scheme '{scheme}'. LiteLLM's database "
+        "features (virtual keys, store_model_in_db, spend tracking) require "
+        "PostgreSQL; use a 'postgresql://' connection string. SQLite and other "
+        "engines are not supported. "
+        "See https://docs.litellm.ai/docs/proxy/virtual_keys"
+    )
+
 
 class DatabaseURLSettings(BaseSettings):
     """Discrete ``DATABASE_*`` env vars, loaded once at process start.
@@ -239,6 +274,24 @@ class DatabaseURLSettings(BaseSettings):
             url += f"?schema={schema}"
         return url
 
+    def _raise_for_unsupported_scheme(self) -> None:
+        """Reject an operator-pinned non-PostgreSQL writer/reader URL.
+
+        The componentized entrypoints (gateway / backend / migrations) call
+        ``apply_to_env`` and then hand the URL straight to Prisma, bypassing
+        the CLI's own guard. A pinned URL flows through untouched, so validate
+        it here too rather than letting Prisma stall on an unusable scheme.
+        """
+        for env_var, url in (
+            ("DATABASE_URL", self.database_url),
+            ("DATABASE_URL_READ_REPLICA", self.database_url_read_replica),
+        ):
+            if not url:
+                continue
+            bad_scheme = unsupported_db_scheme(url)
+            if bad_scheme is not None:
+                raise RuntimeError(unsupported_db_scheme_message(env_var, bad_scheme))
+
     def apply_to_env(self) -> bool:
         """Write the assembled URL(s) into ``os.environ``.
 
@@ -246,6 +299,7 @@ class DatabaseURLSettings(BaseSettings):
         password auth that assembled a fresh URL). False means there was
         nothing to do — an operator-pinned URL, or no discrete fields.
         """
+        self._raise_for_unsupported_scheme()
         wrote_writer = False
         writer_url = self.build_writer_url()
         if writer_url is not None:

litellm/proxy/proxy_cli.py

@@ -1195,6 +1195,25 @@ def run_server(
             os.getenv("DATABASE_URL", None) is not None
             or os.getenv("DIRECT_URL", None) is not None
         ):
+            from litellm.proxy.db.db_url_settings import (
+                unsupported_db_scheme,
+                unsupported_db_scheme_message,
+            )
+
+            for _db_env in ("DATABASE_URL", "DIRECT_URL"):
+                _candidate_url = os.getenv(_db_env)
+                if _candidate_url is None:
+                    continue
+                _bad_scheme = unsupported_db_scheme(_candidate_url)
+                if _bad_scheme is not None:
+                    print(  # noqa
+                        f"\033[1;31mLiteLLM Proxy: "
+                        f"{unsupported_db_scheme_message(_db_env, _bad_scheme)}"
+                        "\033[0m",
+                        file=sys.stderr,
+                        flush=True,
+                    )
+                    sys.exit(1)
             try:
                 from litellm.secret_managers.main import get_secret
 

tests/test_litellm/proxy/db/test_db_url_settings.py

@@ -16,7 +16,11 @@ from unittest.mock import patch
 
 import pytest
 
-from litellm.proxy.db.db_url_settings import DatabaseURLSettings
+from litellm.proxy.db.db_url_settings import (
+    DatabaseURLSettings,
+    unsupported_db_scheme,
+    unsupported_db_scheme_message,
+)
 
 
 def _apply() -> bool:
@@ -287,3 +291,77 @@ def test_password_reader_uses_own_credentials(monkeypatch):
         os.environ["DATABASE_URL_READ_REPLICA"]
         == "postgresql://litellm_ro:ro_pw@reader.example.com:5432/litellm_db"
     )
+
+
+@pytest.mark.parametrize(
+    "url",
+    [
+        "postgresql://u:p@host:5432/db",
+        "postgres://u:p@host:5432/db",
+        "POSTGRESQL://u:p@host:5432/db",
+        "postgresql://host/db?schema=public",
+    ],
+)
+def test_unsupported_db_scheme_accepts_postgres(url):
+    assert unsupported_db_scheme(url) is None
+
+
+@pytest.mark.parametrize(
+    "url,scheme",
+    [
+        ("sqlite:///data/litellm.db", "sqlite"),
+        ("sqlite:///./local.db", "sqlite"),
+        ("mysql://u:p@host:3306/db", "mysql"),
+        ("mssql://host/db", "mssql"),
+    ],
+)
+def test_unsupported_db_scheme_rejects_non_postgres(url, scheme):
+    assert unsupported_db_scheme(url) == scheme
+
+
+def test_unsupported_db_scheme_does_not_echo_schemeless_credentials():
+    """A malformed schemeless DSN must not leak its embedded credentials
+    through the return value (which callers log)."""
+    leaky = "litellm:s3cr3t_password@db.internal:5432/litellm"
+
+    result = unsupported_db_scheme(leaky)
+
+    assert result is not None
+    assert "s3cr3t_password" not in result
+    assert "db.internal" not in result
+
+
+def test_apply_to_env_rejects_pinned_sqlite_writer(monkeypatch):
+    """Componentized entrypoints pin DATABASE_URL and call apply_to_env; a
+    sqlite writer must raise here rather than reach Prisma."""
+    monkeypatch.setenv("DATABASE_URL", "sqlite:///data/litellm.db")
+
+    with pytest.raises(RuntimeError, match="sqlite"):
+        _apply()
+
+    # The bad URL must not have been propagated as a usable connection string.
+    assert os.environ["DATABASE_URL"] == "sqlite:///data/litellm.db"
+
+
+def test_apply_to_env_rejects_pinned_non_postgres_reader(monkeypatch):
+    monkeypatch.setenv("DATABASE_URL", "postgresql://u:p@writer.example.com:5432/db")
+    monkeypatch.setenv(
+        "DATABASE_URL_READ_REPLICA", "mysql://u:p@reader.example.com:3306/db"
+    )
+
+    with pytest.raises(RuntimeError, match="DATABASE_URL_READ_REPLICA.*mysql"):
+        _apply()
+
+
+def test_apply_to_env_accepts_pinned_postgres(monkeypatch):
+    monkeypatch.setenv("DATABASE_URL", "postgresql://u:p@host:5432/db")
+
+    # Operator-pinned URL: nothing reassembled, no error.
+    assert _apply() is False
+
+
+def test_unsupported_db_scheme_message_names_var_and_scheme():
+    msg = unsupported_db_scheme_message("DIRECT_URL", "sqlite")
+    assert "DIRECT_URL" in msg
+    assert "sqlite" in msg
+    assert "postgresql://" in msg

tests/test_litellm/proxy/test_proxy_cli.py

@@ -1708,6 +1708,57 @@ class TestRunServerDbSetup:
                 use_migrate=True, use_v2_resolver=False
             )
 
+    @patch("subprocess.run")
+    @patch("atexit.register")
+    @patch("litellm.proxy.db.prisma_client.PrismaManager.setup_database")
+    @patch("litellm.proxy.db.check_migration.check_prisma_schema_diff")
+    @patch("litellm.proxy.db.prisma_client.should_update_prisma_schema")
+    def test_startup_exits_on_non_postgres_database_url(
+        self,
+        mock_should_update_schema,
+        mock_check_schema_diff,
+        mock_setup_database,
+        mock_atexit_register,
+        mock_subprocess_run,
+    ):
+        """A sqlite DATABASE_URL must exit immediately, before any prisma call,
+        instead of stalling on a migration against the postgresql-only schema."""
+        from litellm.proxy.proxy_cli import run_server
+
+        mock_subprocess_run.return_value = MagicMock(returncode=0)
+        mock_should_update_schema.return_value = True
+
+        mock_proxy_module = MagicMock(
+            app=MagicMock(),
+            ProxyConfig=MagicMock(),
+            KeyManagementSettings=MagicMock(),
+            save_worker_config=MagicMock(),
+        )
+
+        clean_env = {
+            k: v
+            for k, v in os.environ.items()
+            if k not in ("DATABASE_URL", "DIRECT_URL")
+        }
+        clean_env["DATABASE_URL"] = "sqlite:///data/litellm.db"
+
+        with (
+            patch.dict(os.environ, clean_env, clear=True),
+            patch.dict(
+                "sys.modules",
+                {
+                    "proxy_server": mock_proxy_module,
+                    "litellm.proxy.proxy_server": mock_proxy_module,
+                },
+            ),
+        ):
+            with pytest.raises(SystemExit) as exc_info:
+                run_server.main(
+                    ["--local", "--skip_server_startup"], standalone_mode=False
+                )
+            assert exc_info.value.code == 1
+            mock_setup_database.assert_not_called()
+
 
 # --- Module-level helpers for worker startup hook tests ---