Migration Guide

1.6.0 → 1.7.0: Voyager ER Diagram 关系字段重构

Voyager ER diagram 的关系展示方式从「FK 字段出发」改为「relationship name 字段出发」。

变更说明

项目	旧行为	新行为
Node 中的关系字段	显示 FK 字段（如 `user_id`），标记为 `is_object`	显示 relationship name + 目标类型（如 `owner: User`）
边的起点	从 FK 字段（如 `user_id`）出发	从 relationship 字段（如 `owner`）出发
Toggle "Object fields"	显示 FK 字段	显示 relationship 字段

影响

仅影响 ErDiagramDotBuilder（Voyager 可视化）
ErDiagram（Mermaid 生成器）不受影响
公共 API 无变更，无需迁移代码

rpc → use_case Refactor

The RPC module has been fully refactored into the UseCase pattern. Key changes:

Old Name	New Name
`RpcService`	`UseCaseService`
`create_rpc_mcp_server`	`create_use_case_mcp_server`
`create_rpc_voyager`	`create_use_case_voyager`
`RpcVoyager`	`UseCaseVoyager`

MCP Tool Changes

Changed from three layers to four layers, adding list_apps layer for multi-app management:

Old Tool	New Tool
`list_services()`	`list_apps()` → `list_services(app_name)`
`describe_service(service_name)`	`describe_service(app_name, service_name)`
`call_rpc(service_name, method_name, params)`	`call_use_case(app_name, service_name, method_name, params)`

Code Migration

# Before (rpc)
from sqlmodel_nexus.rpc import RpcService, create_rpc_mcp_server

class SprintService(RpcService):
    ...

mcp = create_rpc_mcp_server(
    services=[SprintService, TaskService],
    name="Project API",
)

# After (use_case)
from sqlmodel_nexus.use_case import UseCaseService, UseCaseAppConfig, create_use_case_mcp_server

class SprintService(UseCaseService):
    ...

mcp = create_use_case_mcp_server(
    apps=[
        UseCaseAppConfig(
            name="project",
            services=[SprintService, TaskService],
            description="Project management",
        ),
    ],
    name="Project UseCase API",
)

New Features

Multi-app management: Organize multiple apps via UseCaseAppConfig
FromContext: Support parameter injection from MCP context
Case-insensitive lookup: app_name lookup is case-insensitive

1.3.x → 1.4.0: RpcServiceConfig Removal (Historical)

create_rpc_mcp_server and create_rpc_voyager no longer accept RpcServiceConfig configuration dicts — pass RpcService subclass lists directly.

# Before (1.3.x)
from sqlmodel_nexus import RpcServiceConfig, create_rpc_mcp_server

mcp = create_rpc_mcp_server(
    services=[
        RpcServiceConfig(name="task", service=TaskService, description="..."),
        RpcServiceConfig(name="sprint", service=SprintService, description="..."),
    ],
)

# After (1.4.0)
from sqlmodel_nexus import create_rpc_mcp_server

mcp = create_rpc_mcp_server(
    services=[TaskService, SprintService],
)

1.3.2 → 1.3.3: Loader(str) Removal

The Loader('relationship_name') string lookup pattern has been removed.

# Before (1.3.2)
def resolve_owner(self, loader=Loader("owner")):
    return loader.load(self.owner_id)

# After (1.3.3) — use DataLoader class or async function
def resolve_owner(self, loader=Loader(UserLoader)):
    return loader.load(self.owner_id)

Note: Implicit auto-loading already covers common scenarios. When the field name matches a relationship and the type is compatible, you don't need to write resolve_* methods.

class TaskDTO(DefineSubset):
    __subset__ = (Task, ("id", "title", "owner_id"))
    owner: UserDTO | None = None   # Auto-loaded, no resolve_* needed