Question 217097 in Javascript Question posted in
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Javascript – how fix error: MongoNotConnectedError: Client must be connected before running operations

HY all , I have a problem when I running this code:-

the file productinit.js

const product = require('../model/product');
const mongoose= require('mongoose');

const connectDB = async () => {
    await mongoose.connect('mongodb://127.0.0.1:27017/orders', {bufferTimeout: null});
    console.log('Connected to MongoDB');
  };
  connectDB();

const products = [
    new product({
        imagePath:"/images/about/a1.png",
        productName: "iphone 8+ ",
        price: 200,
        information:
        { 
        displaySize: 6.5,
        storageCapacity: 64,
        CameraResolution: 16,
        numberOfSIM: "Dual SIM"
        }}),

    new product({
        imagePath:"/images/about/a2.png",
        productName: "iphone 8 ",
        price: 240,
        information:
        { 
            displaySize: 5.5,
            storageCapacity: 64,
            CameraResolution: 16,
            numberOfSIM: "Dual SIM"
        }}),
 
     new product({
         imagePath:"/images/about/a3.png",
         productName: "iphone 7+ ",
         price: 180,
         information:
            { 
                displaySize: 6.1,
                storageCapacity: 64,
                CameraResolution: 15,
                numberOfSIM: "Dl SIM"
        }}),
    
    new product({
        imagePath:"/images/about/a4.png",
        productName: "iphone 7 ",
        price: 180,
        information:
                { 
                    displaySize: 6.1,
                    storageCapacity: 32,
                    CameraResolution: 15,
                    numberOfSIM: "Dl SIM"
        }}),
        
    new product({
            imagePath:"/images/about/a5.png",
            productName: "iphone 7+ ",
            price: 180,
            information:
            { 
                displaySize: 6.1,
                storageCapacity: 64,
                CameraResolution: 15,
                numberOfSIM: "Dl SIM"
        }}),

    new product({
                imagePath:"/images/about/a6.png",
                productName: "iphone 7+ ",
                price: 180,
                information:
                { 
                    displaySize: 6.1,
                    storageCapacity: 64,
                    CameraResolution: 15,
                    numberOfSIM: "Dl SIM"
        }}),
        
]

var done = 0;
mongoose.connect('mongodb://127.0.0.1:27017/orders');

for (var i = 0; i < products.length; i++) {
    console.log(i);
    var doc = products[i].save().then(() => console.log("Product saved")).catch(err => console.log(err));
    console.log(doc);
    done++;
    if (done === products.length) {
        mongoose.disconnect();
    }
}

the file product.js

const mongoose = require('mongoose');

const productSchema = mongoose.Schema({
    imagePath:{type:String, required:true},
    productName:{type:String, required:true},
    price:{type:Number, required:true},
    information:
    {
        required:true,
        type:
        {
            displaySize: Number,
            storageCapacity:Number,
            CameraResolution: Number,
            numberOfSIM: String
        }
    }
});


module.exports=mongoose.model('product',productSchema)

,display this error(how can fix it):

0
Promise { <pending> }
1
Promise { <pending> }
2
Promise { <pending> }
3
Promise { <pending> }
4
Promise { <pending> }
5
Promise { <pending> }
Connected to MongoDB
MongoNotConnectedError: Client must be connected before running operations
    at executeOperationAsync (C:coursesnode-jsshopping-cartnode_modulesmongodbliboperationsexecute_operation.js:23:19)
    at C:coursesnode-jsshopping-cartnode_modulesmongodbliboperationsexecute_operation.js:12:45
    at maybeCallback (C:coursesnode-jsshopping-cartnode_modulesmongodblibutils.js:293:21)
    at executeOperation (C:coursesnode-jsshopping-cartnode_modulesmongodbliboperationsexecute_operation.js:12:38)
    at Collection.insertOne (C:coursesnode-jsshopping-cartnode_modulesmongodblibcollection.js:157:57)
    at NativeCollection.<computed> [as insertOne] (C:coursesnode-jsshopping-cartnode_modulesmongooselibdriversnode-mongodb-nativecollection.js:243:33)
    at Collection.doQueue (C:coursesnode-jsshopping-cartnode_modulesmongooselibcollection.js:128:23)
    at C:coursesnode-jsshopping-cartnode_modulesmongooselibcollection.js:75:24
    at process.processTicksAndRejections (node:internal/process/task_queues:77:11) {
  [Symbol(errorLabels)]: Set(0) {}
}
MongoNotConnectedError: Client must be connected before running operations
    at executeOperationAsync (C:coursesnode-jsshopping-cartnode_modulesmongodbliboperationsexecute_operation.js:23:19)
    at C:coursesnode-jsshopping-cartnode_modulesmongodbliboperationsexecute_operation.js:12:45
    at maybeCallback (C:coursesnode-jsshopping-cartnode_modulesmongodblibutils.js:293:21)
    at executeOperation (C:coursesnode-jsshopping-cartnode_modulesmongodbliboperationsexecute_operation.js:12:38)
    at Collection.insertOne (C:coursesnode-jsshopping-cartnode_modulesmongodblibcollection.js:157:57)
    at NativeCollection.<computed> [as insertOne] (C:coursesnode-jsshopping-cartnode_modulesmongooselibdriversnode-mongodb-nativecollection.js:243:33)
    at Collection.doQueue (C:coursesnode-jsshopping-cartnode_modulesmongooselibcollection.js:128:23)
    at C:coursesnode-jsshopping-cartnode_modulesmongooselibcollection.js:75:24
    at process.processTicksAndRejections (node:internal/process/task_queues:77:11) {
  [Symbol(errorLabels)]: Set(0) {}
}
MongoNotConnectedError: Client must be connected before running operations
    at executeOperationAsync (C:coursesnode-jsshopping-cartnode_modulesmongodbliboperationsexecute_operation.js:23:19)
    at C:coursesnode-jsshopping-cartnode_modulesmongodbliboperationsexecute_operation.js:12:45
    at maybeCallback (C:coursesnode-jsshopping-cartnode_modulesmongodblibutils.js:293:21)
    at executeOperation (C:coursesnode-jsshopping-cartnode_modulesmongodbliboperationsexecute_operation.js:12:38)
    at Collection.insertOne (C:coursesnode-jsshopping-cartnode_modulesmongodblibcollection.js:157:57)
    at NativeCollection.<computed> [as insertOne] (C:coursesnode-jsshopping-cartnode_modulesmongooselibdriversnode-mongodb-nativecollection.js:243:33)
    at Collection.doQueue (C:coursesnode-jsshopping-cartnode_modulesmongooselibcollection.js:128:23)
    at C:coursesnode-jsshopping-cartnode_modulesmongooselibcollection.js:75:24
    at process.processTicksAndRejections (node:internal/process/task_queues:77:11) {
  [Symbol(errorLabels)]: Set(0) {}
}
MongoNotConnectedError: Client must be connected before running operations
    at executeOperationAsync (C:coursesnode-jsshopping-cartnode_modulesmongodbliboperationsexecute_operation.js:23:19)
    at C:coursesnode-jsshopping-cartnode_modulesmongodbliboperationsexecute_operation.js:12:45
    at maybeCallback (C:coursesnode-jsshopping-cartnode_modulesmongodblibutils.js:293:21)
    at executeOperation (C:coursesnode-jsshopping-cartnode_modulesmongodbliboperationsexecute_operation.js:12:38)
    at Collection.insertOne (C:coursesnode-jsshopping-cartnode_modulesmongodblibcollection.js:157:57)
    at NativeCollection.<computed> [as insertOne] (C:coursesnode-jsshopping-cartnode_modulesmongooselibdriversnode-mongodb-nativecollection.js:243:33)
    at Collection.doQueue (C:coursesnode-jsshopping-cartnode_modulesmongooselibcollection.js:128:23)
    at C:coursesnode-jsshopping-cartnode_modulesmongooselibcollection.js:75:24
    at process.processTicksAndRejections (node:internal/process/task_queues:77:11) {
  [Symbol(errorLabels)]: Set(0) {}
}
MongoNotConnectedError: Client must be connected before running operations
    at executeOperationAsync (C:coursesnode-jsshopping-cartnode_modulesmongodbliboperationsexecute_operation.js:23:19)
    at C:coursesnode-jsshopping-cartnode_modulesmongodbliboperationsexecute_operation.js:12:45
    at maybeCallback (C:coursesnode-jsshopping-cartnode_modulesmongodblibutils.js:293:21)
    at executeOperation (C:coursesnode-jsshopping-cartnode_modulesmongodbliboperationsexecute_operation.js:12:38)
    at Collection.insertOne (C:coursesnode-jsshopping-cartnode_modulesmongodblibcollection.js:157:57)
    at NativeCollection.<computed> [as insertOne] (C:coursesnode-jsshopping-cartnode_modulesmongooselibdriversnode-mongodb-nativecollection.js:243:33)
    at Collection.doQueue (C:coursesnode-jsshopping-cartnode_modulesmongooselibcollection.js:128:23)
    at C:coursesnode-jsshopping-cartnode_modulesmongooselibcollection.js:75:24
    at process.processTicksAndRejections (node:internal/process/task_queues:77:11) {
  [Symbol(errorLabels)]: Set(0) {}
}
MongoNotConnectedError: Client must be connected before running operations
    at executeOperationAsync (C:coursesnode-jsshopping-cartnode_modulesmongodbliboperationsexecute_operation.js:23:19)
    at C:coursesnode-jsshopping-cartnode_modulesmongodbliboperationsexecute_operation.js:12:45
    at maybeCallback (C:coursesnode-jsshopping-cartnode_modulesmongodblibutils.js:293:21)
    at executeOperation (C:coursesnode-jsshopping-cartnode_modulesmongodbliboperationsexecute_operation.js:12:38)
    at Collection.insertOne (C:coursesnode-jsshopping-cartnode_modulesmongodblibcollection.js:157:57)
    at NativeCollection.<computed> [as insertOne] (C:coursesnode-jsshopping-cartnode_modulesmongooselibdriversnode-mongodb-nativecollection.js:243:33)
    at Collection.doQueue (C:coursesnode-jsshopping-cartnode_modulesmongooselibcollection.js:128:23)
    at C:coursesnode-jsshopping-cartnode_modulesmongooselibcollection.js:75:24
    at process.processTicksAndRejections (node:internal/process/task_queues:77:11) {
  [Symbol(errorLabels)]: Set(0) {}
}

if i use
'mongodb://localhost:27017/orders'instead of'mongodb://127.0.0.1:27017/orders'

,the error will be:

MongooseError: Operation `products.insertOne()` buffering timed out after 10000ms at Timeout

err = new ServerSelectionError();
^
MongooseServerSelectionError: connect ECONNREFUSED ::1:27017

Tags:

2

Answers


  1. 0

    First thing i noticed is that your database connection is already established in the connectDB() function, so there’s no need to connect again before the loop. Secondly, the save() method returns a promise, but your function is not an asynchronous one. Try this instead:

    async function saveProducts() {
try {
    await mongoose.connect('mongodb://127.0.0.1:27017/orders');

    for (const prod of products) {
        console.log(prod);
        const doc = await prod.save();
        console.log("Product saved:", doc);
    }

    mongoose.disconnect();
} catch (error) {
    console.error("Error saving products:", error);
}
}

saveProducts();

    That should handle the promise returned

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  2. 0

    https://www.mongodb.com/languages/mern-stack-tutorial

    Use this link to setup your MERN project & connecting MongoDB.

    Login or Signup to reply.
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