feat: 新增 /run 接口，在 go-judge 沙箱中编译运行 C/C++

Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>

runner.py

@@ -0,0 +1,117 @@
+import os
+
+import httpx
+
+# go-judge 沙箱地址，docker-compose 里是 code-judge 容器
+GOJUDGE_URL = os.getenv("GOJUDGE_URL", "http://code-judge:5050")
+
+# 状态码沿用前端（原 Judge0）的约定
+STATUS_ACCEPTED = 3
+STATUS_COMPILE_ERROR = 6
+STATUS_RUNTIME_ERROR = 11
+
+SECOND = 1_000_000_000  # go-judge 的时间单位是纳秒
+MB = 1024 * 1024
+OUTPUT_MAX = 64 * 1024
+
+LANGUAGES = {
+    "c": {
+        "source": "main.c",
+        "compile": ["/usr/bin/gcc", "main.c", "-o", "main", "-lm"],
+    },
+    "cpp": {
+        "source": "main.cpp",
+        "compile": ["/usr/bin/g++", "main.cpp", "-o", "main"],
+    },
+}
+
+STATUS_MESSAGES = {
+    "Time Limit Exceeded": "运行超时",
+    "Memory Limit Exceeded": "内存超出限制",
+    "Output Limit Exceeded": "输出超出限制",
+    "Signalled": "程序异常终止",
+}
+
+
+class RunError(Exception):
+    """沙箱不可用等非用户代码导致的错误"""
+
+
+def _cmd(args: list[str], stdin: str, cpu: int, memory: int, **extra) -> dict:
+    return {
+        "args": args,
+        "env": ["PATH=/usr/bin:/bin"],
+        "files": [
+            {"content": stdin},
+            {"name": "stdout", "max": OUTPUT_MAX},
+            {"name": "stderr", "max": OUTPUT_MAX},
+        ],
+        "cpuLimit": cpu * SECOND,
+        "clockLimit": cpu * 2 * SECOND,
+        "memoryLimit": memory * MB,
+        "procLimit": 50,
+        "copyOut": ["stdout", "stderr"],
+        **extra,
+    }
+
+
+async def _run(client: httpx.AsyncClient, cmd: dict) -> dict:
+    try:
+        response = await client.post("/run", json={"cmd": [cmd]})
+        response.raise_for_status()
+    except httpx.HTTPError as e:
+        raise RunError(f"判题沙箱不可用：{e}")
+    result = response.json()[0]
+    if result["status"] == "Internal Error":
+        raise RunError(result.get("error") or "判题沙箱内部错误")
+    return result
+
+
+def _output(result: dict) -> str:
+    # 与原来 Judge0 的 redirect_stderr_to_stdout 效果接近：stdout 在前，stderr 在后
+    files = result.get("files", {})
+    return (files.get("stdout", "") + files.get("stderr", "")).strip()
+
+
+async def run_code(language: str, code: str, stdin: str) -> dict:
+    config = LANGUAGES[language]
+    async with httpx.AsyncClient(base_url=GOJUDGE_URL, timeout=30) as client:
+        compiled = await _run(
+            client,
+            _cmd(
+                config["compile"],
+                "",
+                cpu=10,
+                memory=512,
+                copyIn={config["source"]: {"content": code}},
+                copyOutCached=["main"],
+            ),
+        )
+        if compiled["status"] != "Accepted":
+            return {"status": STATUS_COMPILE_ERROR, "output": _output(compiled)}
+
+        file_id = compiled["fileIds"]["main"]
+        try:
+            result = await _run(
+                client,
+                _cmd(
+                    ["main"],
+                    stdin,
+                    cpu=5,
+                    memory=256,
+                    copyIn={"main": {"fileId": file_id}},
+                ),
+            )
+        finally:
+            try:
+                await client.delete(f"/file/{file_id}")
+            except httpx.HTTPError:
+                pass
+
+    output = _output(result)
+    if result["status"] == "Accepted":
+        return {"status": STATUS_ACCEPTED, "output": output}
+    message = STATUS_MESSAGES.get(result["status"])
+    if message:
+        output = f"{output}\n{message}".strip()
+    return {"status": STATUS_RUNTIME_ERROR, "output": output}