heyalice.app local server template

alice-local-server.ts

import express from 'express';
import { OpenAI } from 'openai';

// Todo: Make sure to add your own OPENAI API KEY to the .env
const initializeOpenAI = () => new OpenAI({ apiKey: process.env.OPENAI_API_KEY });
const initializeServer = () => {
  const app = express();
  app.use(express.json());
  return app;
};

const app = initializeServer();
const openai = initializeOpenAI();

const getFormattedTimestamp = () => new Date().toISOString();
const processStream = async (stream, res) => {
  for await (const chunk of stream) {
    const response = {
      model: "gpt-4",
      created_at: getFormattedTimestamp(),
      message: { content: chunk.choices[0]?.delta?.content || '' },
      done: chunk.choices[0]?.delta?.index === null
    };
    res.write(JSON.stringify(response) + '\n');
  }
};

const respondWithError = (error, res) => {
  res.writeHead(500, { 'Content-Type': 'application/json' });
  console.error('Error processing OpenAI API request:', error);
  res.end();
};

const chatEndpoint = (openai) => async (req, res) => {
  try {
    res.writeHead(200, {
      'Content-Type': 'application/x-ndjson',
      'Transfer-Encoding': 'chunked'
    });

    const stream = await openai.chat.completions.create({
      model: 'gpt-4',
      messages: req.body.messages,
      stream: true,
    });

    await processStream(stream, res);
  } catch (error) {
    respondWithError(error, res);
  }
  res.end();
};

app.post('/api/chat', chatEndpoint(openai));

app.listen(3005, () => {
  console.log('Server running on http://localhost:3005');
});