This is a minimal codebase of getting grammY to work with nextjs pages directory. Please use this version of `next-connect`: `"next-connect": "^0.13.0",`

bot.ts

import { Bot, Context } from "grammy";


export const bot = new Bot<Context>(process.env.TELEGRAM_BOT_TOKEN ?? "");

// attach your middlewaew, commands and other stuff to your bot
// eg. bot.use(myCommands)

  // path: /utils/telegram/bot.ts

start.ts

import { bot } from "./bot";

const WEBAPP_URL = "" // URL to your production main site(eg. https://my-secrete-webapp.tld)

const handleGracefulShutdown = async () => {
  const.info("shutdown");

  await bot.stop();

  process.exit();
};

if (process.env.NODE_ENV==="development") {
  // Graceful shutdown handlers
  process.once("SIGTERM", handleGracefulShutdown);
  process.once("SIGINT", handleGracefulShutdown);
}


export const startTelegramBotInDev = async () => {
  if (!bot.isInited()) {
    bot
      .start({
        onStart: ({ username }) => {
          logger.info({
            msg: "bot running...",
            username,
            at: new Date(),
          });
        },
      })
      .catch((err) => logger.error(err));
  }
};

export const startTelegramBotInProduction = async () => {
  const webhookUrl = `${WEBAPP_URL}/api/telegram-webhook?token=${env.TELEGRAM_BOT_WEBHOOK_TOKEN}`;

    logger.info("fetching  webhook info");
    const webhookInfo = await bot.api.getWebhookInfo();
    logger.info(`existing webhook info fetched: ${webhookInfo.url}`);

    if (webhookInfo.url === webhookUrl) {
      logger.info("Sorry, same url, i don't wanna waste my time here.");
    } else {
      logger.info("deleting existing webhook");
      await bot.api.deleteWebhook();
      console.info("existing webhook deleted");

      logger.info(`setting new webhook to: ${webhookUrl}`);
      await bot.api.setWebhook(webhookUrl);
      console.info(`bot webhook set to: ${webhookUrl}`);
    }
  } catch (err) {
    console.error("failed to delete/set webhook url", err);
  }
};

  // path: /utils/telegram/start.ts

telegram-dev.ts

import { NextApiRequest, NextApiResponse } from "next";
import nc from "next-connect";
import { BotError } from "grammy";

import { startTelegramBotInDev } from ""@/lib/telegram/run";


// this is to test the bot locally by visiting http://localhost:3000/api/telegram-dev?action=start
const handler = nc<NextApiRequest, NextApiResponse>({
  attachParams: true,
  onError: (err, _req, res, next) => {
    if (err instanceof BotError) {
      res.status(200).send({});
    } else {
      console.error(err);
      res.status(500).end("Something broke!");
    }
    next();
  },
})
  .get((req, _res, next) => {
    if (process.env.NODE_ENV==="development") {
      next();
    }
  })
  .get(async (req: NextApiRequest, res: NextApiResponse) => {
    try {
      if (req.query && req.query.action !== "start") {
        res.status(500).send({ error: { message: "Wrong gateway." } });
        return;
      }

      await startTelegramBotInDev();
      res.status(200).send("ok");
    } catch (error) {
      res.status(500).json({ error });
    }
  });

export default handler;
  
 // path: /pages/api/telegram-dev.ts

telegram-webhook.ts

import { NextApiRequest, NextApiResponse } from "next";
import nc from "next-connect";

import { BotError, webhookCallback } from "grammy";
import { bot } from "@/lib/telegram/bot";
import { startTelegramBotInProduction } from "@/lib/telegram/start";

import { isProd } from "~utils/constants";

const handler = nc<NextApiRequest, NextApiResponse>({
  attachParams: true,
  onError: (err, _req, res, next) => {
    if (err instanceof BotError) {
      res.status(200).send({});
    } else {
      res.status(500).end("Something broke!");
    }
    next();
  },
})
  .post((req, _res, next) => {
    if (req.query && req.query.token === process.env.TELEGRAM_BOT_WEBHOOK_TOKEN) {
      next();
    }
  })
  .post(webhookCallback(bot, "next-js"))
  .get(async (req, res) => { 
  // this is used to automatically setup your webhook by visiting https://my-secrete-webapp.tld/api/telegram-webhook?token=[YOUR-BOT-TOKEN]
  // replace [YOUR-BOT-TOKEN] with your telegram bot token
  // only do so after you have deployed your bot in production
    try {
      if (process.env.NODE_ENV !=="production" || (req.query && req.query.token !== process.env.TELEGRAM_BOT_WEBHOOK_TOKEN)) {
        return res.status(500).send({ error: { message: "Wrong gateway." } });
      }

      await startTelegramBotInProduction();
    } catch (err) {
      console.error("telegram bot error", err);
    } finally {
      return res.status(200).send("ok");
    }
  });

export default handler;
  
  // path: /pages/api/telegram-webhook.ts