Node.js & TypeScriptでChatGPT APIを活用（1）：チャットボット開発編

.
├── README.md
├── dist
│   └── index.js
├── src
│   └── index.ts
├── package-lock.json
├── package.json
└── tsconfig.json

$ node install --save openai readline-sync
$ node install --save-dev ts-dotenv @types/readline-sync

const { Configuration, OpenAIApi } = require("openai");

const configuration = new Configuration({
  apiKey: process.env.OPENAI_API_KEY,
});
const openai = new OpenAIApi(configuration);

const completion = await openai.createChatCompletion({
  model: "gpt-3.5-turbo",
  messages: [{role: "user", content: "Hello world"}],
});
console.log(completion.data.choices[0].message);

import {
  ChatCompletionRequestMessageRoleEnum,
  Configuration,
  OpenAIApi,
} from 'openai';
import { load } from 'ts-dotenv';

const env = load({
  OPENAI_API_KEY: String, //①
});

const configuration = new Configuration({
  apiKey: env.OPENAI_API_KEY, //②
});

const openai = new OpenAIApi(configuration); //③

(async () => {
  try {
    const response = await openai.createChatCompletion({
      model: 'gpt-3.5-turbo', //④
      messages: [
        {
          role: ChatCompletionRequestMessageRoleEnum.User, //⑤
          content: 'ゴリラの生態について教えてください', //⑥
        },
      ],
    });
    const answer = response.data.choices[0].message?.content; //⑦
    console.log(answer);
  } catch (error) {
    console.log(error);
  }
})();

$ npm run build

$ node dist/index.js

import {
  ChatCompletionRequestMessage,
  ChatCompletionRequestMessageRoleEnum,
  Configuration,
  OpenAIApi,
} from 'openai';
import { load } from 'ts-dotenv';
import * as readlineSync from 'readline-sync';

type Message = {
  inputText: string;
  completionText: string;
};

const env = load({
  OPENAI_API_KEY: String,
});

const configuration = new Configuration({
  apiKey: env.OPENAI_API_KEY,
});

const openai = new OpenAIApi(configuration);

const CHAT_GPT_SYSTEM_PROMPT = '孫悟空になりきって回答して下さい。'; //①

(async () => {
  const history: Message[] = [];
  while (true) {
    const userInput = readlineSync.question('何か聞きたいことはありますか？: '); //②
    const messages: Array<ChatCompletionRequestMessage> = [ //③
      {
        role: ChatCompletionRequestMessageRoleEnum.System, 
        content: CHAT_GPT_SYSTEM_PROMPT,
      },
    ];
    for (const message of history) { //④
      messages.push({
        role: ChatCompletionRequestMessageRoleEnum.User,
        content: message.inputText,
      });
      messages.push({
        role: ChatCompletionRequestMessageRoleEnum.Assistant,
        content: message.completionText,
      });
    }
    messages.push({ role: 'user', content: userInput }); //⑤
    try {
      const completion = await openai.createChatCompletion({
        model: 'gpt-3.5-turbo',
        messages: messages,
        max_tokens: 256,
      });
      const completionText = completion.data.choices[0].message;
      console.log(completionText);
      if (completionText) {
        history.push({ //⑥
          inputText: userInput,
          completionText: completionText.toString(),
        });
      }
      const userInputAgain = readlineSync.question( //⑦
        '\nChatGPTとの会話を続けますか? (Y/N)'
      );
      if (userInputAgain.toUpperCase() === 'N') {
        return;
      } else if (userInputAgain.toUpperCase() !== 'Y') {
        console.log("不正な値です。'Y' か 'N'を入力してください。");
        return;
      }
    } catch (error) {
      console.log(error);
    }
  }
})();