Hi I am beginner in node js mongodb. I want to insert data in mongodb. First I check user exist in users collection then data insert and after complete process then callback. Please give suggestion
exports.contactSync = function contactSync(data, userId, callback) {
var Promise = require('promise');
MongoClient.connect(Mongo_url, function (err, db) {
assert.equal(null, err);
db.collection('contacts').deleteMany({user_id: userId});
var bulk = db.collection('contacts').initializeOrderedBulkOp(),
counter = 0;
data.forEach(function (doc) {
let promises = [];
db.collection('users').findOne({email: doc.trim()}, {user_id: 1}).then(function (userData) {
promises.push(new Promise(resolve => {
bulk.insert({user_id: userId, contact_id: userData.user_id});
}));
});
counter++;
if (data.length == counter) {
return Promise.all(promises);
bulk.execute(function (err, r) {
// do something with the result
console.log("succes");
});
}
});
if (counter > 0) {
bulk.execute(function (err, result) {
console.log("succes");
callback({'error': 0, 'message': 'Successfull synchronization', 'data': null, 'status': 200});
// do something with the result here
});
}
}
The buld.execute is unreachable
if (data.length == counter) {
return Promise.all(promises);
bulk.execute(function (err, r) {
// do something with the result
console.log("succes");
});
}
you can use inserMany() method to insert bulk data into MongoDB.
example with the promise:
Collection1.insertMany(myData)
.then(function(docs) {
// do something with docs
})
.catch(function(err) {
// error handling here
});
I given the sample you just idea follow the ways for insert bulk data with promise
//var Q = require('q');
//insertData = [{name: "abcd"},{name: "efgh"},{name: "xyz"}]
router.post('/', function(req, res) {
var spec = {};
var deleteData= req.deleteData;
Q(spec).then(function(spec) {
//add your delete records logic
var deferred = Q.defer();
var collection = collection_name;
//here assign your db with collection name
collection.deleteMany(deleteData, function(err, user) {
if (!err && user) {
spec.delete= user;
deferred.resolve(spec);
} else {
spec.message = "Please retry";
deferred.reject(spec);
}
});
return deferred.promise;
}).then(function(spec) {
var deferred = Q.defer();
var collection = collection_name;
//here assign your db with collection name
collection.insertMany(insertData, function(err, user) {
if (!err && user) {
spec.user = user;
deferred.resolve(spec);
} else {
spec.message = "Please retry";
deferred.reject(spec);
}
});
return deferred.promise;
}).then(function(spec) {
res.json(spec);
//send your response
}).fail(function(spec) {
res.json(spec);
//send your error response
});
}
The technical post webpages of this site follow the CC BY-SA 4.0 protocol. If you need to reprint, please indicate the site URL or the original address.Any question please contact:yoyou2525@163.com.