feat(BA-5830): add /v2/app-configs REST endpoints (merged view, BEP-1052 §5)

Mounts the merged-view `AppConfig` surface as REST v2 under
`/v2/app-configs/...`. Shares v2 DTOs and the adapter with the
GraphQL layer added in BA-5829 (#11285). Handler reuses the Fragment
adapter because the merged-view methods live on
`AppConfigFragmentAdapter`.

Endpoints:
- `GET  /v2/app-configs/my/{name}`          — auth (self-service single)
- `POST /v2/app-configs/my/search`          — auth (self-service paginated)
- `POST /v2/app-configs/search`             — superadmin (cross-user)
- `GET  /v2/app-configs/{user_id}/{name}`   — superadmin (read one user's view)

Adds:
- `api/rest/v2/app_config/handler.V2AppConfigHandler` with `my_get` /
  `my_search` / `admin_get` / `admin_search`.
- `api/rest/v2/app_config/registry.register_v2_app_config_routes`.
- `AppConfigMyNamePathParam` + `AppConfigUserNamePathParam` in the
  shared path-params module.
- Handler instantiation + sub-registry wiring in `rest/v2/tree.py`
  (handler takes `adapters.app_config_fragment` — annotated for the
  reviewer).

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

Author: jopemachine

src/ai/backend/manager/api/rest/v2/app_config/__init__.py

@@ -0,0 +1,74 @@
+"""REST v2 handler for the AppConfig merged-view domain (BEP-1052 §5)."""
+
+from __future__ import annotations
+
+import logging
+from http import HTTPStatus
+from typing import TYPE_CHECKING, Final
+
+from ai.backend.common.api_handlers import APIResponse, BodyParam, PathParam
+from ai.backend.common.dto.manager.v2.app_config.request import (
+    GetUserAppConfigInput,
+    SearchAppConfigsInput,
+    SearchMyAppConfigsInput,
+)
+from ai.backend.logging import BraceStyleAdapter
+from ai.backend.manager.api.rest.v2.path_params import (
+    AppConfigMyNamePathParam,
+    AppConfigUserNamePathParam,
+)
+
+if TYPE_CHECKING:
+    from ai.backend.manager.api.adapters.app_config_fragment import AppConfigFragmentAdapter
+
+log: Final = BraceStyleAdapter(logging.getLogger(__spec__.name))
+
+
+class V2AppConfigHandler:
+    """REST v2 handler for the merged-view `AppConfig` surface.
+
+    Mounted at `/v2/app-configs/...`. The adapter lives on the Fragment
+    domain (`app_config_fragment`) because the merged view is computed
+    from fragment rows joined against `app_config_policies`.
+    """
+
+    def __init__(self, *, adapter: AppConfigFragmentAdapter) -> None:
+        self._adapter = adapter
+
+    # ── My (self-service) ────────────────────────────────────────
+
+    async def my_get(
+        self,
+        path: PathParam[AppConfigMyNamePathParam],
+    ) -> APIResponse:
+        """Read the caller's own merged AppConfig for `name`."""
+        result = await self._adapter.my_app_config(path.parsed.name)
+        return APIResponse.build(status_code=HTTPStatus.OK, response_model=result)
+
+    async def my_search(
+        self,
+        body: BodyParam[SearchMyAppConfigsInput],
+    ) -> APIResponse:
+        """Paginated merged-view search over the caller's own AppConfigs."""
+        result = await self._adapter.my_search_app_configs(body.parsed)
+        return APIResponse.build(status_code=HTTPStatus.OK, response_model=result)
+
+    # ── Admin ────────────────────────────────────────────────────
+
+    async def admin_get(
+        self,
+        path: PathParam[AppConfigUserNamePathParam],
+    ) -> APIResponse:
+        """Read a specific user's merged AppConfig (admin only)."""
+        result = await self._adapter.admin_get_user_app_config(
+            GetUserAppConfigInput(user_id=path.parsed.user_id, name=path.parsed.name)
+        )
+        return APIResponse.build(status_code=HTTPStatus.OK, response_model=result)
+
+    async def admin_search(
+        self,
+        body: BodyParam[SearchAppConfigsInput],
+    ) -> APIResponse:
+        """Cross-user merged-view search (admin only)."""
+        result = await self._adapter.admin_search_app_configs(body.parsed)
+        return APIResponse.build(status_code=HTTPStatus.OK, response_model=result)

src/ai/backend/manager/api/rest/v2/app_config/handler.py

@@ -0,0 +1,36 @@
+"""Route registration for v2 AppConfig merged-view endpoints (BEP-1052 §5)."""
+
+from __future__ import annotations
+
+from typing import TYPE_CHECKING
+
+from ai.backend.manager.api.rest.middleware.auth import auth_required, superadmin_required
+from ai.backend.manager.api.rest.routing import RouteRegistry
+
+from .handler import V2AppConfigHandler
+
+if TYPE_CHECKING:
+    from ai.backend.manager.api.rest.types import RouteDeps
+
+
+def register_v2_app_config_routes(
+    handler: V2AppConfigHandler,
+    route_deps: RouteDeps,
+) -> RouteRegistry:
+    """Register all v2 `/v2/app-configs/*` routes (BEP-1052 §4).
+
+    Read-only surface — writes go through `/v2/app-config-fragments/...`
+    (§4). Self-service routes land under the `/my/...` prefix so the
+    adapter can pin `(USER, current_user)` internally; admin routes
+    allow targeting any user id.
+    """
+    reg = RouteRegistry.create("app-configs", route_deps.cors_options)
+
+    # Self-service
+    reg.add("GET", "/my/{name}", handler.my_get, middlewares=[auth_required])
+    reg.add("POST", "/my/search", handler.my_search, middlewares=[auth_required])
+    # Admin
+    reg.add("POST", "/search", handler.admin_search, middlewares=[superadmin_required])
+    reg.add("GET", "/{user_id}/{name}", handler.admin_get, middlewares=[superadmin_required])
+
+    return reg

src/ai/backend/manager/api/rest/v2/app_config/registry.py

@@ -14,6 +14,15 @@ class AppConfigFragmentScopePathParam(BaseRequestModel):
     scope_id: str = Field(description="Scope id (domain name, user id, or `public`).")
 
 
+class AppConfigMyNamePathParam(BaseRequestModel):
+    name: str = Field(description="Policy / config name.")
+
+
+class AppConfigUserNamePathParam(BaseRequestModel):
+    user_id: UUID = Field(description="Target user's UUID (admin only).")
+    name: str = Field(description="Policy / config name.")
+
+
 class DomainNamePathParam(BaseRequestModel):
     domain_name: str = Field(description="Domain name")
 

src/ai/backend/manager/api/rest/v2/path_params.py

@@ -28,6 +28,8 @@ def build_v2_routes(
     # Lazy imports to avoid circular dependencies at module level
     from .agent.handler import V2AgentHandler
     from .agent.registry import register_v2_agent_routes
+    from .app_config.handler import V2AppConfigHandler
+    from .app_config.registry import register_v2_app_config_routes
     from .app_config_fragment.handler import V2AppConfigFragmentHandler
     from .app_config_fragment.registry import register_v2_app_config_fragment_routes
     from .artifact.handler import V2ArtifactHandler
@@ -113,6 +115,9 @@ def build_v2_routes(
 
     # Build all handlers (each takes its individual adapter)
     agent_handler = V2AgentHandler(adapter=adapters.agent)
+    # AppConfig merged-view handler reuses the Fragment adapter because the
+    # merged-view methods live on `AppConfigFragmentAdapter`.
+    app_config_handler = V2AppConfigHandler(adapter=adapters.app_config_fragment)
     app_config_fragment_handler = V2AppConfigFragmentHandler(adapter=adapters.app_config_fragment)
     artifact_handler = V2ArtifactHandler(adapter=adapters.artifact)
     artifact_registry_handler = V2ArtifactRegistryHandler(adapter=adapters.artifact_registry)
@@ -168,6 +173,7 @@ def build_v2_routes(
 
     # Add all domain sub-registries
     v2_reg.add_subregistry(register_v2_agent_routes(agent_handler, route_deps))
+    v2_reg.add_subregistry(register_v2_app_config_routes(app_config_handler, route_deps))
     v2_reg.add_subregistry(
         register_v2_app_config_fragment_routes(app_config_fragment_handler, route_deps)
     )