[WIP] add agent run controllers

.gitignore

@@ -11,6 +11,7 @@ run
 .DS_Store
 .tmp
 .vscode
+.claude
 
 package-lock.json
 yarn.lock

plugin/langchain/app/controller/RunsController.ts

@@ -0,0 +1,129 @@
+import {
+  HTTPController,
+  HTTPMethod,
+  HTTPMethodEnum,
+  HTTPBody,
+  Context,
+  Middleware,
+} from '@eggjs/tegg';
+import type { EggContext } from '@eggjs/tegg';
+import type { RunCreateDTO } from './types';
+import { streamSSE } from '../../lib/sse';
+import { RunCreate } from './schemas';
+import { ZodErrorMiddleware } from '../middleware/ZodErrorMiddleware';
+
+/**
+ * LangGraph Runs Controller
+ * 处理 Run 相关的 HTTP 请求
+ */
+@HTTPController({
+  path: '/api',
+})
+@Middleware(ZodErrorMiddleware)
+export class RunsController {
+  /**
+   * POST /api/runs/stream
+   * 流式创建无状态 Run (SSE)
+   *
+   * 对应 LangGraph runs.mts 的 api.post("/runs/stream", ...) 端点
+   */
+  @HTTPMethod({
+    method: HTTPMethodEnum.POST,
+    path: '/runs/stream',
+  })
+  async streamStatelessRun(@Context() ctx: EggContext, @HTTPBody() payload: RunCreateDTO) {
+    const validated = RunCreate.parse(payload);
+    console.log('streamStatelessRun', validated);
+    // Mock: 生成一个假的 run_id
+    const runId = `run_${Date.now()}_${Math.random().toString(36).substring(7)}`;
+
+    // 设置 Content-Location header
+    ctx.set('Content-Location', `/runs/${runId}`);
+
+    // 类型断言帮助访问 input 中的 messages
+    const inputData = validated.input as { messages?: Array<{ role: string; content: string }> } | undefined;
+
+    // 使用 SSE 流式返回
+    return streamSSE(ctx, async (stream) => {
+      // 如果需要在断开连接时取消，创建 AbortSignal
+      // const cancelOnDisconnect = validated.on_disconnect === 'cancel'
+      //   ? getDisconnectAbortSignal(ctx, stream)
+      //   : undefined;
+
+      try {
+        // TODO: 调用 runs service 的 stream.join 方法获取运行结果
+        // for await (const { event, data } of runs().stream.join(
+        //   runId,
+        //   undefined,
+        //   {
+        //     cancelOnDisconnect,
+        //     lastEventId: validated.stream_resumable ? "-1" : undefined,
+        //     ignore404: true,
+        //   },
+        //   auth
+        // )) {
+        //   await stream.writeSSE({ data: JSON.stringify(data), event });
+        // }
+
+        // Mock 实现：模拟 SSE 流式响应
+        // 1. 发送 metadata 事件
+        await stream.writeSSE({
+          event: 'metadata',
+          data: JSON.stringify({
+            run_id: runId,
+            assistant_id: validated.assistant_id || 'mock_assistant',
+          }),
+        });
+
+        await stream.sleep(100);
+
+        // 2. 发送 values 事件 - 模拟开始处理
+        await stream.writeSSE({
+          event: 'values',
+          data: JSON.stringify({
+            messages: [
+              {
+                role: 'user',
+                content: inputData?.messages?.[0]?.content || 'Hello',
+              },
+            ],
+          }),
+        });
+
+        await stream.sleep(500);
+
+        // 3. 发送 values 事件 - 模拟 AI 响应
+        await stream.writeSSE({
+          event: 'values',
+          data: JSON.stringify({
+            messages: [
+              {
+                role: 'user',
+                content: inputData?.messages?.[0]?.content || 'Hello',
+              },
+              {
+                role: 'assistant',
+                content: `Mock response to: ${inputData?.messages?.[0]?.content || 'Hello'}`,
+              },
+            ],
+          }),
+        });
+
+        await stream.sleep(200);
+
+        // 4. 发送 end 事件
+        await stream.writeSSE({
+          event: 'end',
+          data: JSON.stringify({
+            run_id: runId,
+            status: 'completed',
+          }),
+        });
+      } catch (error) {
+        console.error('Error streaming run:', error);
+        throw error;
+      }
+    });
+  }
+
+}