Feat : Kiro MITM

src/mitm/handlers/base.js

@@ -0,0 +1,50 @@
+const { log, err } = require("../logger");
+
+const ROUTER_BASE = "http://localhost:20128";
+const API_KEY = process.env.ROUTER_API_KEY;
+
+/**
+ * Send body to 9Router at the given path and return the fetch Response object
+ */
+async function fetchRouter(openaiBody, path = "/v1/chat/completions") {
+  const response = await fetch(`${ROUTER_BASE}${path}`, {
+    method: "POST",
+    headers: {
+      "Content-Type": "application/json",
+      ...(API_KEY && { "Authorization": `Bearer ${API_KEY}` })
+    },
+    body: JSON.stringify(openaiBody)
+  });
+
+  if (!response.ok) {
+    const errText = await response.text().catch(() => "");
+    throw new Error(`[${response.status}]: ${errText}`);
+  }
+
+  return response;
+}
+
+/**
+ * Pipe SSE stream from router directly to client response
+ */
+async function pipeSSE(routerRes, res) {
+  const ct = routerRes.headers.get("content-type") || "application/json";
+  const resHeaders = { "Content-Type": ct, "Cache-Control": "no-cache", "Connection": "keep-alive" };
+  if (ct.includes("text/event-stream")) resHeaders["X-Accel-Buffering"] = "no";
+  res.writeHead(200, resHeaders);
+
+  if (!routerRes.body) {
+    res.end(await routerRes.text().catch(() => ""));
+    return;
+  }
+
+  const reader = routerRes.body.getReader();
+  const decoder = new TextDecoder();
+  while (true) {
+    const { done, value } = await reader.read();
+    if (done) { res.end(); break; }
+    res.write(decoder.decode(value, { stream: true }));
+  }
+}
+
+module.exports = { fetchRouter, pipeSSE };