加一套抓真实请求做预设对比的工具，并把三份预设的机制差异记进 README。

2026-10-22 20:07:33 +08:00
parent 18f034bc2d
commit ed09e5c831
21 changed files with 1735 additions and 0 deletions
@@ -0,0 +1,166 @@
+/**
+ * 假上游：实现够用的 OpenAI 兼容端点，把收到的原始请求体原样落盘。
+ *
+ * 用法：
+ *   node capture-server.mjs --label st --port 8801
+ *
+ * 落盘目录默认 ./captures（相对本文件）。
+ * 每个请求一个 <label>-<序号>.json，内容 { label, receivedAt, method, url, headers, body }。
+ * body 是原始字符串，diff 工具再解析 —— 保留原文便于核对是否有我们没建模的字段。
+ */
+import { createServer } from "node:http";
+import { mkdirSync, writeFileSync } from "node:fs";
+import path from "node:path";
+import { fileURLToPath } from "node:url";
+
+const HERE = path.dirname(fileURLToPath(import.meta.url));
+
+function readArgs(argv) {
+  const out = { label: "unknown", port: 8800, out: path.join(HERE, "captures") };
+  for (let i = 0; i < argv.length; i++) {
+    const key = argv[i];
+    const next = argv[i + 1];
+    if (key === "--label") out.label = String(next);
+    else if (key === "--port") out.port = Number(next);
+    else if (key === "--out") out.out = path.resolve(String(next));
+  }
+  return out;
+}
+
+const args = readArgs(process.argv.slice(2));
+mkdirSync(args.out, { recursive: true });
+
+const REPLY_TEXT = "[[mock-reply]] 收到。";
+const REPLY_REASONING = "[[mock-reasoning]] 想一下。";
+
+function capture(req, url, raw) {
+  const stamp = new Date().toISOString().replace(/[:.]/g, "-");
+  const seq = String(globalThis.__captureSeq = (globalThis.__captureSeq ?? 0) + 1).padStart(3, "0");
+  const file = path.join(args.out, `${args.label}-${seq}-${stamp}.json`);
+  const payload = {
+    label: args.label,
+    receivedAt: new Date().toISOString(),
+    method: req.method,
+    url,
+    headers: {
+      "content-type": req.headers["content-type"] ?? null,
+      authorization: req.headers.authorization ? "<redacted>" : null,
+    },
+    body: raw,
+  };
+  writeFileSync(file, JSON.stringify(payload, null, 2), "utf8");
+  // 只写一行摘要，不把正文打到控制台
+  let charCount = raw.length;
+  try {
+    const parsed = JSON.parse(raw);
+    charCount = Array.isArray(parsed.messages)
+      ? parsed.messages.reduce((n, m) => n + String(m.content ?? "").length, 0)
+      : charCount;
+  } catch {
+    /* 非 JSON 就按原长度记 */
+  }
+  console.log(`[capture:${args.label}] ${req.method} ${url} -> ${path.basename(file)} (messages 正文 ${charCount} 字)`);
+  return file;
+}
+
+function readBody(req) {
+  return new Promise((resolve, reject) => {
+    const chunks = [];
+    req.on("data", (c) => chunks.push(c));
+    req.on("end", () => resolve(Buffer.concat(chunks).toString("utf8")));
+    req.on("error", reject);
+  });
+}
+
+function sseHead(res) {
+  res.writeHead(200, {
+    "Content-Type": "text/event-stream; charset=utf-8",
+    "Cache-Control": "no-cache",
+    Connection: "keep-alive",
+  });
+}
+
+function sseChunk(delta, finishReason = null) {
+  return `data: ${JSON.stringify({
+    id: "chatcmpl-mock",
+    object: "chat.completion.chunk",
+    created: Math.floor(Date.now() / 1000),
+    model: "mock-model",
+    choices: [{ index: 0, delta, finish_reason: finishReason }],
+  })}\n\n`;
+}
+
+const server = createServer(async (req, res) => {
+  const url = req.url ?? "/";
+  if (req.method === "GET" && url.includes("/models")) {
+    res.writeHead(200, { "Content-Type": "application/json; charset=utf-8" });
+    res.end(
+      JSON.stringify({
+        object: "list",
+        data: [{ id: "mock-model", object: "model", owned_by: "mock" }],
+      }),
+    );
+    return;
+  }
+
+  const raw = await readBody(req);
+  if (req.method !== "POST") {
+    res.writeHead(404).end("not found");
+    return;
+  }
+
+  let body = {};
+  try {
+    body = JSON.parse(raw);
+  } catch {
+    /* 保留原文，下面按默认处理 */
+  }
+
+  capture(req, url, raw);
+
+  if (url.includes("/embeddings")) {
+    res.writeHead(200, { "Content-Type": "application/json; charset=utf-8" });
+    res.end(JSON.stringify({ object: "list", data: [{ embedding: [0] }] }));
+    return;
+  }
+
+  if (url.includes("/completions")) {
+    if (body.stream) {
+      sseHead(res);
+      const chunks = [];
+      if (body.reasoning_effort && body.reasoning_effort !== "none") {
+        chunks.push(sseChunk({ role: "assistant", reasoning_content: REPLY_REASONING }));
+      }
+      chunks.push(sseChunk({ role: "assistant", content: REPLY_TEXT }));
+      chunks.push(sseChunk({}, "stop"));
+      chunks.push("data: [DONE]\n\n");
+      res.end(chunks.join(""));
+      return;
+    }
+    res.writeHead(200, { "Content-Type": "application/json; charset=utf-8" });
+    res.end(
+      JSON.stringify({
+        id: "chatcmpl-mock",
+        object: "chat.completion",
+        created: Math.floor(Date.now() / 1000),
+        model: "mock-model",
+        choices: [
+          {
+            index: 0,
+            message: { role: "assistant", content: REPLY_TEXT },
+            finish_reason: "stop",
+          },
+        ],
+        usage: { prompt_tokens: 100, completion_tokens: 10, total_tokens: 110 },
+      }),
+    );
+    return;
+  }
+
+  res.writeHead(200, { "Content-Type": "application/json; charset=utf-8" });
+  res.end(JSON.stringify({ ok: true }));
+});
+
+server.listen(args.port, "127.0.0.1", () => {
+  console.log(`[capture:${args.label}] listening on http://127.0.0.1:${args.port}/v1 -> ${args.out}`);
+});