throw new error_1.MongoNotConnectedError('Client must be connected before running operations');

About the Community Welcome
1

Pinged your deployment. You successfully connected to MongoDB!
new User: { name: ‘Rakib Hasain’, email: ‘rakibkhancmt@gmail.com’ }
G:\simple-mongodb-app\node_modules\mongodb\lib\operations\execute_operation.js:40
throw new error_1.MongoNotConnectedError(‘Client must be connected before running operations’);
^

MongoNotConnectedError: Client must be connected before running operations
at executeOperation (G:\simple-mongodb-app\node_modules\mongodb\lib\operations\execute_operation.js:40:19)
at Collection.insertOne (G:\simple-mongodb-app\node_modules\mongodb\lib\collection.js:154:63)
at G:\simple-mongodb-app\index.js:34:39
at Layer.handle [as handle_request] (G:\simple-mongodb-app\node_modules\express\lib\router\layer.js:95:5)
at next (G:\simple-mongodb-app\node_modules\express\lib\router\route.js:149:13)
at Route.dispatch (G:\simple-mongodb-app\node_modules\express\lib\router\route.js:119:3)
at Layer.handle [as handle_request] (G:\simple-mongodb-app\node_modules\express\lib\router\layer.js:95:5)
at G:\simple-mongodb-app\node_modules\express\lib\router\index.js:284:15
at Function.process_params (G:\simple-mongodb-app\node_modules\express\lib\router\index.js:346:12)
at next (G:\simple-mongodb-app\node_modules\express\lib\router\index.js:280:10) {
[Symbol(errorLabels)]: Set(0) {}
}

Node.js v20.12.2
[nodemon] app crashed - waiting for file changes before starting…

2

Ah, the dreaded MongoNotConnectedError… I feel your frustration! This error means the MongoDB client isn’t connected before you try to run operations like insertOne().

Let’s break this down:

  1. Are you calling client.connect()?
    Before running any operations on MongoDB, you need to make sure the client is properly connected. Typically, you would do something like this:
const { MongoClient } = require('mongodb');
const uri = "your MongoDB URI here";

const client = new MongoClient(uri);

async function run() {
  try {
    // Connect to the MongoDB client
    await client.connect();

    const database = client.db("yourDatabase");
    const collection = database.collection("yourCollection");

    // Insert operation after successful connection
    const result = await collection.insertOne({ name: 'Rakib Hasain', email: 'rakibkhancmt@gmail.com' });
    console.log(`New user inserted with ID: ${result.insertedId}`);
  } catch (err) {
    console.error(err);
  } finally {
    // Ensure the client is closed when done
    await client.close();
  }
}

run().catch(console.dir);

2.Key things to check:*

  • Ensure that client.connect() is called… and awaited before performing any database operations.
  • Make sure your MongoDB URI is correct and your cluster is reachable.
  1. Event-driven frameworks like Express
    If you’re using something like Express (which it looks like you are), it’s easy to try database operations too early. Make sure the connection to MongoDB is established before starting any operations. You could also establish the connection once at the start of your app and reuse the client.
  2. Nodemon restarting…
    Not directly related, but if nodemon is crashing, the above error is likely the culprit. Once you handle the connection properly, the app should stop crashing.

Try these suggestions and let me know how it goes!

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