#!/usr/bin/env -S npm run tsn -T

// This file demonstrates how to stream from the server as a text/plain

// response with express and the stream async iterator.

import OpenAI from 'openai';

import express, { Request, Response } from 'express';

const openai = new OpenAI();

const app = express();

app.use(express.text());

// This endpoint can be called with:

//

// curl 127.0.0.1:3000 -N -X POST -H 'Content-Type: text/plain' \

// --data 'Can you explain why dogs are better than cats?'

//

// Or consumed with fetch:

//

// fetch('http://localhost:3000', {

// method: 'POST',

// body: 'Tell me why dogs are better than cats',

// }).then(async res => {

// const decoder = new TextDecoder();

// for await (const chunk of res.body) {

// console.log(`chunk: ${decoder.decode(chunk)}`);

// }

// })

//

app.post('/', async (req: Request, res: Response) => {

try {

console.log('Received request:', req.body);

const stream = await openai.chat.completions.create({

model: 'gpt-3.5-turbo',

stream: true,

messages: [{ role: 'user', content: req.body }],

});

res.header('Content-Type', 'text/plain');

// Sends each content stream chunk-by-chunk, such that the client

// ultimately receives a single string.

for await (const chunk of stream) {

res.write(chunk.choices[0]?.delta.content || '');

}

res.end();

} catch (e) {

console.error(e);

}

});

app.listen('3000', () => {

console.log('Started proxy express server');

});