feat(API): 添加代码执行 API 路由

- 创建 /api/code/execute 接口
- 集成 Piston API 支持多语言远程执行
- 添加执行超时和错误处理

src/app/api/code/execute/route.ts

@@ -0,0 +1,143 @@
+/**
+ * Piston API 代理
+ * 避免 CORS 问题，转发请求到 Piston API
+ */
+
+import { NextRequest, NextResponse } from 'next/server';
+
+// Piston API 公共端点
+const PISTON_API_URL = 'https://emkc.org/api/v2/piston';
+
+// 执行超时时间（秒）
+const EXECUTION_TIMEOUT = 30;
+
+// 请求体类型
+interface ExecuteRequest {
+  language: string;
+  version: string;
+  files: Array<{
+    name?: string;
+    content: string;
+  }>;
+  stdin?: string;
+  args?: string[];
+  compile_args?: string[];
+  run_args?: string[];
+  compile_timeout?: number;
+  run_timeout?: number;
+  compile_memory_limit?: number;
+  run_memory_limit?: number;
+}
+
+// Piston API 响应类型
+interface PistonResponse {
+  language: string;
+  version: string;
+  run: {
+    stdout: string;
+    stderr: string;
+    output: string;
+    code: number;
+    signal: string | null;
+  };
+  compile?: {
+    stdout: string;
+    stderr: string;
+    output: string;
+    code: number;
+    signal: string | null;
+  };
+}
+
+export async function POST(request: NextRequest) {
+  try {
+    const body: ExecuteRequest = await request.json();
+
+    // 验证请求
+    if (!body.language || !body.files || body.files.length === 0) {
+      return NextResponse.json(
+        { error: '缺少必要参数: language, files' },
+        { status: 400 }
+      );
+    }
+
+    // 设置超时
+    const controller = new AbortController();
+    const timeoutId = setTimeout(() => controller.abort(), EXECUTION_TIMEOUT * 1000);
+
+    // 构建请求
+    const pistonRequest: ExecuteRequest = {
+      language: body.language,
+      version: body.version || '*',
+      files: body.files,
+      stdin: body.stdin || '',
+      args: body.args || [],
+      compile_args: body.compile_args || [],
+      run_args: body.run_args || [],
+      compile_timeout: body.compile_timeout || 10000,
+      run_timeout: body.run_timeout || 10000,
+      compile_memory_limit: body.compile_memory_limit || -1,
+      run_memory_limit: body.run_memory_limit || -1,
+    };
+
+    // 发送请求到 Piston API
+    const response = await fetch(`${PISTON_API_URL}/execute`, {
+      method: 'POST',
+      headers: {
+        'Content-Type': 'application/json',
+      },
+      body: JSON.stringify(pistonRequest),
+      signal: controller.signal,
+    });
+
+    clearTimeout(timeoutId);
+
+    if (!response.ok) {
+      const errorText = await response.text();
+      return NextResponse.json(
+        { error: `Piston API 错误: ${response.status} - ${errorText}` },
+        { status: response.status }
+      );
+    }
+
+    const result: PistonResponse = await response.json();
+
+    return NextResponse.json(result);
+  } catch (error) {
+    if (error instanceof Error && error.name === 'AbortError') {
+      return NextResponse.json(
+        { error: `执行超时（${EXECUTION_TIMEOUT}秒）` },
+        { status: 408 }
+      );
+    }
+
+    console.error('Piston API proxy error:', error);
+    return NextResponse.json(
+      { error: error instanceof Error ? error.message : '执行失败' },
+      { status: 500 }
+    );
+  }
+}
+
+// 获取支持的语言列表
+export async function GET() {
+  try {
+    const response = await fetch(`${PISTON_API_URL}/runtimes`);
+
+    if (!response.ok) {
+      return NextResponse.json(
+        { error: '获取语言列表失败' },
+        { status: response.status }
+      );
+    }
+
+    const runtimes = await response.json();
+    return NextResponse.json(runtimes);
+  } catch (error) {
+    console.error('Failed to fetch runtimes:', error);
+    return NextResponse.json(
+      { error: '获取语言列表失败' },
+      { status: 500 }
+    );
+  }
+}