index.js

import express from 'express';
import dotenv from 'dotenv';
import axios from 'axios';
import rateLimit from 'express-rate-limit';

dotenv.config();

const {
  OPENWEBUI_URL,
  OPENWEBUI_USER,
  OPENWEBUI_PASS,
  PORT
} = process.env;

let token = null;
let tokenExpiry = 0;

const app = express();
app.use(express.json());

// Basic rate limiting: 60 requests per minute per IP
const limiter = rateLimit({
  windowMs: 60 * 1000,
  max: 60
});
app.use('/api/chat', limiter);

// Refresh JWT from OpenWebUI
async function refreshToken() {
  const now = Date.now();
  if (token && now < tokenExpiry - 30000) return token; // 30s buffer

  try {
    // const res = await axios.post(`${OPENWEBUI_URL}/api/auth/login`, {
    //   username: OPENWEBUI_USER,
    //   password: OPENWEBUI_PASS
    // });

    const res = await axios.post(`${OPENWEBUI_URL}/api/sessions`, {
      username: OPENWEBUI_USER,
      password: OPENWEBUI_PASS
    }, {
      headers: {
        'Content-Type': 'application/json',
        'Accept': 'application/json'
      }
    });

    token = res.data.access_token;
    tokenExpiry = now + 60 * 60 * 1000; // Assume 1hr token life
    return token;
  } catch (err) {
    console.error('Auth error:', err.response?.data || err.message);
    throw new Error('Authentication with OpenWebUI failed.');
  }
}

// Proxy chat request (stream or non-stream)
app.post('/api/chat', async (req, res) => {
  const modelInput = req.body;
  if (!modelInput?.messages) return res.status(400).send({ error: 'Invalid input' });

  try {
    const jwt = await refreshToken();
    const headers = {
      Authorization: `Bearer ${jwt}`,
      'Content-Type': 'application/json',
      Accept: 'application/json'
    };

    // Handle streaming mode
    if (modelInput.stream) {
      const stream = await axios({
        url: `${OPENWEBUI_URL}/api/chat/completions`,
        method: 'POST',
        headers,
        data: modelInput,
        responseType: 'stream'
      });

      res.setHeader('Content-Type', 'text/event-stream');
      stream.data.pipe(res);
    } else {
      const response = await axios.post(
        `${OPENWEBUI_URL}/api/chat/completions`,
        modelInput,
        { headers }
      );
      res.json(response.data);
    }
  } catch (error) {
    console.error('Chat error:', error.response?.data || error.message);
    res.status(500).json({ error: 'Proxy chat failed.' });
  }
});

// Serve static frontend from /static
import path from 'path';
import { fileURLToPath } from 'url';
const __dirname = path.dirname(fileURLToPath(import.meta.url));
app.use('/static', express.static(path.join(__dirname, 'static')));

app.listen(PORT, () => {
  console.log(`🔐 OpenWebUI Proxy running on http://localhost:${PORT}`);
});