Feat : Kiro MITM

src/mitm/handlers/antigravity.js

@@ -0,0 +1,20 @@
+const { err } = require("../logger");
+const { fetchRouter, pipeSSE } = require("./base");
+
+/**
+ * Intercept Antigravity (Gemini) request — replace model and forward to router
+ */
+async function intercept(req, res, bodyBuffer, mappedModel) {
+  try {
+    const body = JSON.parse(bodyBuffer.toString());
+    body.model = mappedModel;
+    const routerRes = await fetchRouter(body);
+    await pipeSSE(routerRes, res);
+  } catch (error) {
+    err(`[antigravity] ${error.message}`);
+    if (!res.headersSent) res.writeHead(500, { "Content-Type": "application/json" });
+    res.end(JSON.stringify({ error: { message: error.message, type: "mitm_error" } }));
+  }
+}
+
+module.exports = { intercept };

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 };

src/mitm/handlers/copilot.js

@@ -0,0 +1,35 @@
+const { err } = require("../logger");
+const { fetchRouter, pipeSSE } = require("./base");
+
+// Map Copilot endpoint → 9Router path
+const URL_MAP = {
+  "/chat/completions": "/v1/chat/completions",
+  "/v1/messages":      "/v1/messages",
+  "/responses":        "/v1/responses",
+};
+
+function resolveRouterPath(reqUrl) {
+  for (const [pattern, routerPath] of Object.entries(URL_MAP)) {
+    if (reqUrl.includes(pattern)) return routerPath;
+  }
+  return "/v1/chat/completions";
+}
+
+/**
+ * Intercept Copilot request — replace model and forward to matching 9Router endpoint
+ */
+async function intercept(req, res, bodyBuffer, mappedModel) {
+  try {
+    const body = JSON.parse(bodyBuffer.toString());
+    body.model = mappedModel;
+    const routerPath = resolveRouterPath(req.url);
+    const routerRes = await fetchRouter(body, routerPath);
+    await pipeSSE(routerRes, res);
+  } catch (error) {
+    err(`[copilot] ${error.message}`);
+    if (!res.headersSent) res.writeHead(500, { "Content-Type": "application/json" });
+    res.end(JSON.stringify({ error: { message: error.message, type: "mitm_error" } }));
+  }
+}
+
+module.exports = { intercept };

src/mitm/handlers/cursor.js

@@ -0,0 +1,15 @@
+/**
+ * Cursor MITM handler — coming soon
+ * This feature is currently under development.
+ */
+async function intercept(req, res) {
+  res.writeHead(501, { "Content-Type": "application/json" });
+  res.end(JSON.stringify({
+    error: {
+      message: "Cursor MITM support is coming soon.",
+      type: "not_implemented"
+    }
+  }));
+}
+
+module.exports = { intercept };

src/mitm/handlers/kiro.js

@@ -0,0 +1,20 @@
+const { err } = require("../logger");
+const { fetchRouter, pipeSSE } = require("./base");
+
+/**
+ * Intercept Kiro request — replace model and forward to router
+ */
+async function intercept(req, res, bodyBuffer, mappedModel) {
+  try {
+    const body = JSON.parse(bodyBuffer.toString());
+    body.model = mappedModel;
+    const routerRes = await fetchRouter(body);
+    await pipeSSE(routerRes, res);
+  } catch (error) {
+    err(`[Kiro] ${error.message}`);
+    if (!res.headersSent) res.writeHead(500, { "Content-Type": "application/json" });
+    res.end(JSON.stringify({ error: { message: error.message, type: "mitm_error" } }));
+  }
+}
+
+module.exports = { intercept };