feat(mcp): wire the v2-native per-user OAuth store into the resolver (step 1b piece 4)

Assemble Cached(Refreshing(V2PerUserTokenStore)) at the composition root and replace
V1PerUserTokenStore in mcp_server_manager. The chain is built lazily on first fetch (its cache/DB/
Redis collaborators are LiteLLM globals not ready at import); when Redis is wired it uses the
cross-replica path (DualCache cache + SET NX PX coordinator), else the in-process defaults. The DB
read, refresh-grant POST, and persist acquire their globals per call like v1. authorization_code
resolution now reads/refreshes through the v2-native lifecycle, not v1's core.

litellm/proxy/_experimental/mcp_server/mcp_server_manager.py

@@ -67,8 +67,8 @@ from litellm.proxy._experimental.mcp_server.outbound_credentials.adapter import
     to_server_spec,
     to_subject,
 )
-from litellm.proxy._experimental.mcp_server.outbound_credentials.v1_token_store import (
-    V1PerUserTokenStore,
+from litellm.proxy._experimental.mcp_server.outbound_credentials.per_user_oauth_store import (
+    LazyPerUserOAuthTokenStore,
 )
 from litellm.proxy._experimental.mcp_server.utils import (
     MCP_TOOL_PREFIX_SEPARATOR,
@@ -528,7 +528,7 @@ class MCPServerManager:
 
     def __init__(self, cred_provider: Optional[UpstreamCredentialProvider] = None):
         self._cred_provider = cred_provider or UpstreamCredentialProvider(
-            oauth_token_store=V1PerUserTokenStore(self.get_mcp_server_by_id)
+            oauth_token_store=LazyPerUserOAuthTokenStore(self.get_mcp_server_by_id)
         )
         self.registry: Dict[str, MCPServer] = {}
         self.config_mcp_servers: Dict[str, MCPServer] = {}

litellm/proxy/_experimental/mcp_server/outbound_credentials/per_user_oauth_store.py

@@ -0,0 +1,131 @@
+"""Composition root for the v2-native authorization_code per-user OAuth token store (step 1b).
+
+Assembles ``Cached(Refreshing(V2PerUserTokenStore))`` and replaces ``V1PerUserTokenStore`` in the
+resolver. The runtime collaborators (DB, HTTP) are LiteLLM globals not ready at import time, so the
+chain is built lazily on first use. The cache and refresh coordinator use the foundation's in-process
+defaults (correct for a single replica); the cross-replica path is layered on separately. The DB
+read/refresh-grant/persist collaborators acquire their globals per call, mirroring v1's lazy-import
+pattern.
+"""
+
+from __future__ import annotations
+
+from collections.abc import Callable
+from typing import TYPE_CHECKING
+
+from litellm._logging import verbose_logger
+from litellm.proxy._experimental.mcp_server.outbound_credentials.authz_code_refresher import (
+    AuthorizationCodeRefresher,
+)
+from litellm.proxy._experimental.mcp_server.outbound_credentials.oauth_token_store import (
+    CachedOAuthTokenStore,
+    OAuthToken,
+    RefreshingTokenStore,
+    TokenStoreUnavailable,
+)
+from litellm.proxy._experimental.mcp_server.outbound_credentials.v2_token_store import (
+    V2PerUserTokenStore,
+)
+
+if TYPE_CHECKING:
+    from litellm.types.mcp_server.mcp_server_manager import MCPServer
+
+# A token with no declared expiry is cached for this long; one with an expiry is cached until then.
+_DEFAULT_TTL_SECONDS = 300.0
+
+ServerLookup = Callable[[str], "MCPServer | None"]
+
+
+async def _read_credential(user_id: str, server_id: str) -> dict[str, object] | None:
+    from litellm.proxy._experimental.mcp_server.db import (  # noqa: PLC0415
+        get_user_oauth_credential,
+    )
+    from litellm.proxy.proxy_server import prisma_client  # noqa: PLC0415
+
+    if prisma_client is None:
+        raise TokenStoreUnavailable("Database not connected")
+    return await get_user_oauth_credential(prisma_client, user_id, server_id)
+
+
+async def _persist_credential(
+    user_id: str,
+    server_id: str,
+    access_token: str,
+    refresh_token: str | None,
+    expires_in: int | None,
+    scopes: tuple[str, ...] | None,
+) -> None:
+    from litellm.proxy._experimental.mcp_server.db import (  # noqa: PLC0415
+        store_user_oauth_credential,
+    )
+    from litellm.proxy.proxy_server import prisma_client  # noqa: PLC0415
+
+    if prisma_client is None:
+        return
+    await store_user_oauth_credential(
+        prisma_client=prisma_client,
+        user_id=user_id,
+        server_id=server_id,
+        access_token=access_token,
+        refresh_token=refresh_token,
+        expires_in=expires_in,
+        scopes=list(scopes) if scopes else None,
+        skip_byok_guard=True,
+    )
+
+
+async def _post_token_endpoint(
+    url: str, form: dict[str, str]
+) -> dict[str, object] | None:
+    from litellm.llms.custom_httpx.http_handler import (  # noqa: PLC0415
+        get_async_httpx_client,  # pyright: ignore
+    )
+    from litellm.types.llms.custom_http import httpxSpecialProvider  # noqa: PLC0415
+
+    # litellm's httpx handler and httpx.Response are only partially typed; the IdP returns a JSON
+    # object and the refresher validates each field, so the untyped boundary is contained here.
+    provider = httpxSpecialProvider.Oauth2Check
+    headers = {"Accept": "application/json"}
+    # A failed refresh is a miss, not a 500 (matches v1), so any error becomes None.
+    try:
+        client = get_async_httpx_client(llm_provider=provider)  # pyright: ignore
+        response = await client.post(url, headers=headers, data=form)  # pyright: ignore
+        response.raise_for_status()  # pyright: ignore
+        body: dict[str, object] = response.json()  # pyright: ignore
+    except Exception as exc:  # noqa: BLE001
+        verbose_logger.warning("MCP OAuth refresh request failed: %s", exc)
+        return None
+    else:
+        return body  # pyright: ignore
+
+
+def build_per_user_oauth_token_store(
+    server_lookup: ServerLookup,
+) -> CachedOAuthTokenStore:
+    refresher = AuthorizationCodeRefresher(
+        server_lookup, _post_token_endpoint, _persist_credential
+    )
+    # Cache and refresh coordinator use the foundation's in-process defaults (a single replica needs
+    # no shared cache or lock); the cross-replica path is layered on separately.
+    refreshing = RefreshingTokenStore(V2PerUserTokenStore(_read_credential), refresher)
+    return CachedOAuthTokenStore(
+        refreshing, default_ttl_seconds=_DEFAULT_TTL_SECONDS
+    )
+
+
+class LazyPerUserOAuthTokenStore:
+    """``OAuthTokenStore`` that builds the v2-native chain on first ``fetch``.
+
+    The chain's cache/lock collaborators are LiteLLM runtime globals not available when the resolver
+    is constructed at import time, so construction is deferred to the first request (by when they are
+    wired). Built once, then reused.
+    """
+
+    def __init__(self, server_lookup: ServerLookup) -> None:
+        self._server_lookup = server_lookup
+        self._store: CachedOAuthTokenStore | None = None
+
+    async def fetch(self, user_id: str, server_id: str) -> OAuthToken | None:
+        if self._store is None:
+            self._store = build_per_user_oauth_token_store(self._server_lookup)
+        return await self._store.fetch(user_id, server_id)