fix: remove serialize_as_any=False to fix EventContext validation error (partial fix)

[Copilot]

概述 / Overview

修复插件系统中 EventContext.event.message_chain 字段验证失败的问题（部分修复）。

When emitting events to plugins, model_dump(serialize_as_any=False) was used in connector.py. This can override the pydantic.SerializeAsAny annotation on the event field, causing subclass-specific fields like message_chain to be lost during serialization in certain Python/Pydantic version combinations.

Fix in LangBot: Remove the explicit serialize_as_any=False parameter to let Pydantic use default behavior respecting the SerializeAsAny annotation.

# Before
event_ctx.model_dump(serialize_as_any=False)

# After  
event_ctx.model_dump()

⚠️ 注意 / Note: 这是部分修复。完整修复需要在 langbot-plugin-sdk 仓库中进行，需要修复以下位置的 model_dump() 调用以确保子类字段被正确序列化：

• cli/run/handler.py 第 144 行
• runtime/plugin/mgr.py 第 511 行

This is a partial fix. The complete fix requires changes in the langbot-plugin-sdk repository to ensure model_dump() calls properly serialize subclass fields.

更改前后对比截图 / Screenshots

修改前 / Before:

ValidationError: 1 validation error for EventContext
event.message_chain
  Field required [type=missing, ...]

修改后 / After:
LangBot now correctly serializes event data when sending to plugins. However, the SDK-side serialization issue may still cause the error until the SDK is also fixed.

检查清单 / Checklist

PR 作者完成 / For PR author

• 阅读仓库贡献指引了吗？ / Have you read the contribution guide?
• 与项目所有者沟通过了吗？ / Have you communicated with the project maintainer?
• 我确定已自行测试所作的更改，确保功能符合预期。 / I have tested the changes and ensured they work as expected.

项目维护者完成 / For project maintainer

• 相关 issues 链接了吗？ / Have you linked the related issues?
• 配置项写好了吗？迁移写好了吗？生效了吗？ / Have you written the configuration items? Have you written the migration? Has it taken effect?
• 依赖加到 pyproject.toml 和 core/bootutils/deps.py 了吗 / Have you added the dependencies to pyproject.toml and core/bootutils/deps.py?
• 文档编写了吗？ / Have you written the documentation?

Original prompt

---

This section details on the original issue you should resolve

<issue_title>[Bug]: 1 validation error for EventContext event.message_chain Field required [type=missing, ...]</issue_title>
<issue_description>### Runtime environment

v4.5.4

Exception

详细报错信息：
[2025-11-29 20:29:27.597] handler.py (146) - [INFO] : [Action] emit_event
[11-29 20:29:27.598] process.py (39) - [INFO] : Processing request from group_cidgZaf+Yel/9rYcSF9/nKEow== (6): 你好
Traceback (most recent call last):
File "/Volumes/Disk-1tb/LangBot/.venv/lib/python3.11/site-packages/langbot_plugin/runtime/io/handler.py", line 121, in handle_message
response = await response
^^^^^^^^^^^^^^
File "/Volumes/Disk-1tb/LangBot/.venv/lib/python3.11/site-packages/langbot_plugin/runtime/io/handlers/control.py", line 175, in emit_event
emitted_plugins, event_context = await self.context.plugin_mgr.emit_event(
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/Volumes/Disk-1tb/LangBot/.venv/lib/python3.11/site-packages/langbot_plugin/runtime/plugin/mgr.py", line 519, in emit_event
event_context = EventContext.model_validate(resp["event_context"])
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/Volumes/Disk-1tb/LangBot/.venv/lib/python3.11/site-packages/pydantic/main.py", line 716, in model_validate
return cls.pydantic_validator.validate_python(
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
pydantic_core._pydantic_core.ValidationError: 1 validation error for EventContext
event.message_chain
Field required [type=missing, input_value={'reply_message_chain': N...er_message_alter': None}, input_type=dict]
For further information visit https://errors.pydantic.dev/2.12/v/missing
[2025-11-29 20:29:27.602] handler.py (146) - [INFO] : [Action] emit_event
[11-29 20:29:27.602] pipelinemgr.py (253) - [ERROR] : Error processing query 6 stage=MessageProcessor : ActionCallError: ValidationError: 1 validation error for EventContext
event.message_chain
Field required [type=missing, input_value={'reply_message_chain': N...er_message_alter': None}, input_type=dict]
For further information visit https://errors.pydantic.dev/2.12/v/missing
[11-29 20:29:27.603] pipelinemgr.py (254) - [ERROR] : Traceback: Traceback (most recent call last):
File "/Volumes/Disk-1tb/LangBot/.venv/lib/python3.11/site-packages/langbot_plugin/runtime/io/handler.py", line 175, in call_action
raise ActionCallError(f"{response.message}")
langbot_plugin.entities.io.errors.ActionCallError: ValidationError: 1 validation error for EventContext
event.message_chain
Field required [type=missing, input_value={'reply_message_chain': N...er_message_alter': None}, input_type=dict]
For further information visit https://errors.pydantic.dev/2.12/v/missing

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/Volumes/Disk-1tb/LangBot/src/langbot/pkg/pipeline/pipelinemgr.py", line 250, in process_query
await self._execute_from_stage(0, query)
File "/Volumes/Disk-1tb/LangBot/src/langbot/pkg/pipeline/pipelinemgr.py", line 206, in _execute_from_stage
async for sub_result in result:
File "/Volumes/Disk-1tb/LangBot/src/langbot/pkg/pipeline/process/process.py", line 52, in generator
async for result in handler_to_use.handle(query):
File "/Volumes/Disk-1tb/LangBot/src/langbot/pkg/pipeline/process/handlers/chat.py", line 49, in handle
event_ctx = await self.ap.plugin_connector.emit_event(event, bound_plugins)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/Volumes/Disk-1tb/LangBot/src/langbot/pkg/plugin/connector.py", line 376, in emit_event
event_ctx_result = await self.handler.emit_event(
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/Volumes/Disk-1tb/LangBot/src/langbot/pkg/plugin/handler.py", line 560, in emit_event
result = await self.call_action(
^^^^^^^^^^^^^^^^^^^^^^^
File "/Volumes/Disk-1tb/LangBot/.venv/lib/python3.11/site-packages/langbot_plugin/runtime/io/handler.py", line 180, in call_action
raise ActionCallError(f"{e.class.name}: {str(e)}")
langbot_plugin.entities.io.errors.ActionCallError: ActionCallError: ValidationError: 1 validation error for EventContext
event.message_chain
Field required [type=missing, input_value={'reply_message_chain': N...er_message_alter': None}, input_type=dict]
For further information visit https://errors.pydantic.dev/2.12/v/missing

启用的插件：https://github.com/langbot-app/langbot-plugin-demo/tree/main/AIImagePlugin
使用的平台：钉钉
关闭插件后是正常的

Reproduction steps

No response

Enabled plugins

No response</issue_description>

<agent_instructions>中文交流，深度研究 LangBot本体代码、插件代码、插件 SDK 代码以明确准确问题所在</agent_instructions>

Comments on the Issue (you are @copilot in this section)

• Fixes [Bug]: 1 validation error for EventContext event.message_chain Field required [type=missing, ...] #1817

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[the-lazy-me]

@copilot 还是同样报错，可能是插件 sdk 或者是插件https://github.com/langbot-app/langbot-plugin-demo/tree/main/AIImagePlugin的问题

[Copilot]

@copilot 还是同样报错，可能是插件 sdk 或者是插件https://github.com/langbot-app/langbot-plugin-demo/tree/main/AIImagePlugin的问题

经过深入分析，您说得对。问题确实不在 LangBot 本体代码中，而是在插件 SDK (langbot-plugin-sdk) 中。

具体问题位置在 SDK 的以下文件：

1. cli/run/handler.py 第 144 行：event_context.model_dump()
2. runtime/plugin/mgr.py 第 511 行：event_context.model_dump()

这些地方在序列化时可能丢失了子类特有的字段（如 message_chain）。

我的修改 (cd22952) 移除了 serialize_as_any=False 只是确保 LangBot 端发送时数据完整，但如果 SDK 端在处理过程中丢失了数据，问题仍然会存在。

建议在 langbot-plugin-sdk 仓库中修复这个问题，需要确保 model_dump() 调用时子类字段被正确序列化。