MongoDB error connect to DB (Bot telegram) session instalation

[Ekacitta_Wibisono]

Hello,
I want to ask, I’m getting an error while running mongodb for telegram bot. the error is Error connecting to MongoDB: TypeError: session is not a constructor. Here I show the code file database.js

const connectToDatabase = async () => {
  try {
    const uri = process.env.MONGODB_URI;
    const client = new MongoClient(uri, { useNewUrlParser: true, useUnifiedTopology: true });
    await client.connect();
    console.log('Connected to MongoDB successfully');
    const db = client.db();
    const sessions = new session(db, {
      collectionName: 'session',
      sessionName: 'telegrafSessions'
    });
    return { db, sessions };
  } catch (error) {
    console.error('Error connecting to MongoDB:', error);
    throw error;
  }
};

The modules that I installed on database.js

const { MongoClient } = require('mongodb');
const { session } = require('telegraf-session-mongodb');

Here is the index.js file for connecting to the database.js file

const { Telegraf, Markup } = require('telegraf');
const { connectToDatabase, saveUserSession, saveUserLog } = require('./src/database');
// Connect database
connectToDatabase()
.then(({ db, sessions }) => {
    // Middleware session user
    bot.use(sessions.middleware());

    bot.use(async (ctx, next) => {
      ctx.session.db = db; // insert object db session
      await next();
    });

    // Middleware save user telegram
    bot.use((ctx, next) => {
      saveUserSession(db, ctx.session)
        .then(() => next())
        .catch((error) => {
          console.error('Error saving user session:', error);
          ctx.reply('Oops! Something went wrong.');
        });
    });
    // Middleware save log user telegram
    bot.use((ctx, next) => {
      const log = {
        session_id: ctx.session.session_id,
        user_id: ctx.from.id,
        timestamp: new Date(),
        message: ctx.message.text
      };
      saveUserLog(db, log);
      return next();
    });

[Kushagra_Kesav]

Hi @Ekacitta_Wibisono,

Welcome to the MongoDB Community!

@Ekacitta_Wibisono

    const sessions = new session(db, {
      collectionName: 'session',
      sessionName: 'telegrafSessions'
    });

MongoDB: TypeError: session is not a constructor

Based on the shared details, the error doesn’t seems to be related to MongoDB rather it is occurring from the above code snippet because the session is not a constructor so adding a new keyword in-front of it make it throw an error.

So, to avoid this error message first connect to the MongoDB database and then use the connectToDatabase() function to further start a bot. Sharing the code snippet for your reference:

// Connect to the database and return the database object
const connectToDatabase = async () => {
    try {
        const uri = process.env.MONGODB_URI || "mongodb://localhost:27017"; // Use the environment variable if available, otherwise use the local URL
        const client = new MongoClient(uri, { useNewUrlParser: true, useUnifiedTopology: true });
        await client.connect();

        console.log('Connected to MongoDB successfully');

        return client.db(); 
    } catch (error) {
        console.error('Error connecting to MongoDB:', error);
        throw error;
    }
};

// Connect database and start the bot
connectToDatabase()
    .then((db) => {
        const bot = new Telegraf('YOUR_TELEGRAM_BOT_TOKEN'); // Replace 'YOUR_TELEGRAM_BOT_TOKEN' with your actual bot token

        // Middleware to manage user sessions
        bot.use(session(db, { sessionName: 'test', collectionName: 'sessions' })); // Replace 'test' with your actual database name

        bot.use(async (ctx, next) => {
            ctx.db = db; 
            await next();
        });
...

I’ve only briefly tested this out so I recommend evaluating the code in your test environment to see if it suits your use case and requirements.

To learn more, please refer to telegraf-session-mongodb - npm documentation.

Hope the above helps!

Regards,
Kushagra