From 45d99c832e2897a34255c5e36380727fb2c39662 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pawe=C5=82=20Nguyen?= <pawel.nguyen@gmail.com>
Date: Mon, 13 Apr 2026 02:23:42 +0200
Subject: [PATCH] fix(mcp-server): use explicit undici fetch for Node 16+
 compat, bump to 0.1.7

---
 package-lock.json                | 37 ++++++++++++++++++++++++++++++--
 package.json                     |  3 ++-
 src/__tests__/api-client.test.ts |  8 ++++---
 src/api-client.ts                |  1 +
 src/index.ts                     | 10 +++++++++
 5 files changed, 53 insertions(+), 6 deletions(-)

diff --git a/package-lock.json b/package-lock.json
index ca153cf..b4ed5cc 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -1,15 +1,16 @@
 {
   "name": "@cenogram/mcp-server",
-  "version": "0.1.6",
+  "version": "0.1.7",
   "lockfileVersion": 2,
   "requires": true,
   "packages": {
     "": {
       "name": "@cenogram/mcp-server",
-      "version": "0.1.6",
+      "version": "0.1.7",
       "license": "MIT",
       "dependencies": {
         "@modelcontextprotocol/sdk": "^1.28.0",
+        "undici": "^5.29.0",
         "zod": "^3.24.0"
       },
       "bin": {
@@ -601,6 +602,14 @@
         "node": "^18.18.0 || ^20.9.0 || >=21.1.0"
       }
     },
+    "node_modules/@fastify/busboy": {
+      "version": "2.1.1",
+      "resolved": "https://registry.npmjs.org/@fastify/busboy/-/busboy-2.1.1.tgz",
+      "integrity": "sha512-vBZP4NlzfOlerQTnba4aqZoMhE/a9HY7HRqoOPaETQcSQuWEIyZMHGfVu6w9wGtGK5fED5qRs2DteVCjOH60sA==",
+      "engines": {
+        "node": ">=14"
+      }
+    },
     "node_modules/@hono/node-server": {
       "version": "1.19.13",
       "resolved": "https://registry.npmjs.org/@hono/node-server/-/node-server-1.19.13.tgz",
@@ -3721,6 +3730,17 @@
         "url": "https://github.com/sponsors/isaacs"
       }
     },
+    "node_modules/undici": {
+      "version": "5.29.0",
+      "resolved": "https://registry.npmjs.org/undici/-/undici-5.29.0.tgz",
+      "integrity": "sha512-raqeBD6NQK4SkWhQzeYKd1KmIG6dllBOTt55Rmkt4HtI9mwdWtJljnrXjAFUBLTSN67HWrOIZ3EPF4kjUw80Bg==",
+      "dependencies": {
+        "@fastify/busboy": "^2.0.0"
+      },
+      "engines": {
+        "node": ">=14.0"
+      }
+    },
     "node_modules/undici-types": {
       "version": "6.21.0",
       "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-6.21.0.tgz",
@@ -4317,6 +4337,11 @@
         "levn": "^0.4.1"
       }
     },
+    "@fastify/busboy": {
+      "version": "2.1.1",
+      "resolved": "https://registry.npmjs.org/@fastify/busboy/-/busboy-2.1.1.tgz",
+      "integrity": "sha512-vBZP4NlzfOlerQTnba4aqZoMhE/a9HY7HRqoOPaETQcSQuWEIyZMHGfVu6w9wGtGK5fED5qRs2DteVCjOH60sA=="
+    },
     "@hono/node-server": {
       "version": "1.19.13",
       "resolved": "https://registry.npmjs.org/@hono/node-server/-/node-server-1.19.13.tgz",
@@ -6313,6 +6338,14 @@
         }
       }
     },
+    "undici": {
+      "version": "5.29.0",
+      "resolved": "https://registry.npmjs.org/undici/-/undici-5.29.0.tgz",
+      "integrity": "sha512-raqeBD6NQK4SkWhQzeYKd1KmIG6dllBOTt55Rmkt4HtI9mwdWtJljnrXjAFUBLTSN67HWrOIZ3EPF4kjUw80Bg==",
+      "requires": {
+        "@fastify/busboy": "^2.0.0"
+      }
+    },
     "undici-types": {
       "version": "6.21.0",
       "resolved": "https://registry.npmjs.org/undici-types/-/undici-types-6.21.0.tgz",
diff --git a/package.json b/package.json
index ec69526..d13d40c 100644
--- a/package.json
+++ b/package.json
@@ -1,6 +1,6 @@
 {
   "name": "@cenogram/mcp-server",
-  "version": "0.1.6",
+  "version": "0.1.7",
   "description": "MCP Server for Polish real estate transaction data (7M+ transactions from RCN)",
   "type": "module",
   "bin": {
@@ -20,6 +20,7 @@
   },
   "dependencies": {
     "@modelcontextprotocol/sdk": "^1.28.0",
+    "undici": "^5.29.0",
     "zod": "^3.24.0"
   },
   "devDependencies": {
diff --git a/src/__tests__/api-client.test.ts b/src/__tests__/api-client.test.ts
index 3f4d39e..d25366a 100644
--- a/src/__tests__/api-client.test.ts
+++ b/src/__tests__/api-client.test.ts
@@ -1,8 +1,10 @@
 import { describe, it, expect, vi, beforeEach } from "vitest";
 
-// Must mock fetch before importing api-client
-const mockFetch = vi.fn();
-vi.stubGlobal("fetch", mockFetch);
+const { mockFetch } = vi.hoisted(() => ({
+  mockFetch: vi.fn(),
+}));
+
+vi.mock("undici", () => ({ fetch: mockFetch }));
 
 vi.mock("../client-id.js", () => ({
   getClientId: () => "test-client-uuid-1234",
diff --git a/src/api-client.ts b/src/api-client.ts
index 3c73402..80b6924 100644
--- a/src/api-client.ts
+++ b/src/api-client.ts
@@ -1,3 +1,4 @@
+import { fetch, type Response } from "undici";
 import { getClientId } from "./client-id.js";
 
 const BASE_URL = process.env.CENOGRAM_API_URL || "https://cenogram.pl";
diff --git a/src/index.ts b/src/index.ts
index 9285a1d..2467140 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -6,6 +6,16 @@ import { dirname, join } from "node:path";
 import { readFileSync, realpathSync } from "node:fs";
 import { registerTools } from "./tools.js";
 
+// ── Node version check ─────────────────────────────────────────────
+
+const [nodeMajor] = process.versions.node.split(".").map(Number);
+if (nodeMajor != null && nodeMajor < 18) {
+  process.stderr.write(
+    `Warning: @cenogram/mcp-server recommends Node.js >= 18 (current: ${process.version}). ` +
+    "The server will try to run, but some features may not work.\n",
+  );
+}
+
 // ── Version ────────────────────────────────────────────────────────
 
 const __dirname = dirname(fileURLToPath(import.meta.url));