Update the same property of every document of a mo

I have a collection in mongoDb which looks like this

{ 
"slno" : NumberInt(1),
"name" : "Item 1"
} 
{ 
"slno" : NumberInt(2),
"name" : "Item 2"
} 
{ 
"slno" : NumberInt(3),
"name" : "Item 3"
}

I am receiving a request from angularJs frontend to update this collection to

{ 
"slno" : NumberInt(1),
"name" : "Item 3"
} 
{ 
"slno" : NumberInt(2),
"name" : "Item 1"
} 
{ 
"slno" : NumberInt(3),
"name" : "Item 2"
}

I am using Mongoose 5.0 ORM with Node 6.11 and express 4.15. Please help me find the best way to achieve this.

回答1:

You basically want bulkWrite(), which can take the input array of objects and use it to make a "batch" of requests to update the matched documents.

Presuming the array of documents is being sent in req.body.updates, then you would have something like

const Model = require('../models/model');

router.post('/update', (req,res) => {
  Model.bulkWrite(
    req.body.updates.map(({ slno, name }) => 
      ({
        updateOne: {
          filter: { slno },
          update: { $set: { name } }
        }
      })
    )
  })
  .then(result => {
    // maybe do something with the WriteResult
    res.send("ok"); // or whatever response
  })
  .catch(e => {
    // do something with any error
  })
})

This sends a request given the input as:

bulkWrite([
   { updateOne: { filter: { slno: 1 }, update: { '$set': { name: 'Item 3' } } } },
   { updateOne: { filter: { slno: 2 }, update: { '$set': { name: 'Item 1' } } } },
   { updateOne: { filter: { slno: 3 }, update: { '$set': { name: 'Item 2' } } } } ]
)

Which efficiently performs all updates in a single request to the server with a single response.

Also see the core MongoDB documentation on bulkWrite(). That's the documentation for the mongo shell method, but all the options and syntax are exactly the same in most drivers and especially within all JavaScript based drivers.

As a full working demonstration of the method in use with mongoose:

const { Schema } = mongoose = require('mongoose');

const uri = 'mongodb://localhost/test';

mongoose.Promise = global.Promise;
mongoose.set('debug',true);

const testSchema = new Schema({
  slno: Number,
  name: String
});

const Test = mongoose.model('Test', testSchema);

const log = data => console.log(JSON.stringify(data, undefined, 2));

const data = [1,2,3].map(n => ({ slno: n, name: `Item ${n}` }));

const request = [[1,3],[2,1],[3,2]]
  .map(([slno, n]) => ({ slno, name: `Item ${n}` }));

mongoose.connect(uri)
  .then(conn =>
    Promise.all(Object.keys(conn.models).map( k => conn.models[k].remove()))
  )
  .then(() => Test.insertMany(data))
  .then(() => Test.bulkWrite(
    request.map(({ slno, name }) =>
      ({ updateOne: { filter: { slno }, update: { $set: { name } } } })
    )
  ))
  .then(result => log(result))
  .then(() => Test.find())
  .then(data => log(data))
  .catch(e => console.error(e))
  .then(() => mongoose.disconnect());

Or for more modern environments with async/await:

const { Schema } = mongoose = require('mongoose');

const uri = 'mongodb://localhost/test';

mongoose.Promise = global.Promise;
mongoose.set('debug',true);

const testSchema = new Schema({
  slno: Number,
  name: String
});

const Test = mongoose.model('Test', testSchema);

const log = data => console.log(JSON.stringify(data, undefined, 2));

const data = [1,2,3].map(n => ({ slno: n, name: `Item ${n}` }));

const request = [[1,3],[2,1],[3,2]]
  .map(([slno,n]) => ({ slno, name: `Item ${n}` }));

(async function() {

  try {

    const conn = await mongoose.connect(uri)

    await Promise.all(Object.entries(conn.models).map(([k,m]) => m.remove()));

    await Test.insertMany(data);
    let result = await Test.bulkWrite(
      request.map(({ slno, name }) =>
        ({ updateOne: { filter: { slno }, update: { $set: { name } } } })
      )
    );
    log(result);

    let current = await Test.find();
    log(current);

    mongoose.disconnect();

  } catch(e) {
    console.error(e)
  } finally {
    process.exit()
  }

})()

Which loads the initial data and then updates, showing the response object ( serialized ) and the resulting items in the collection after the update is processed:

Mongoose: tests.remove({}, {})
Mongoose: tests.insertMany([ { _id: 5b1b89348f3c9e1cdb500699, slno: 1, name: 'Item 1', __v: 0 }, { _id: 5b1b89348f3c9e1cdb50069a, slno: 2, name: 'Item 2', __v: 0 }, { _id: 5b1b89348f3c9e1cdb50069b, slno: 3, name: 'Item 3', __v: 0 } ], {})
Mongoose: tests.bulkWrite([ { updateOne: { filter: { slno: 1 }, update: { '$set': { name: 'Item 3' } } } }, { updateOne: { filter: { slno: 2 }, update: { '$set': { name: 'Item 1' } } } }, { updateOne: { filter: { slno: 3 }, update: { '$set': { name: 'Item 2' } } } } ], {})
{
  "ok": 1,
  "writeErrors": [],
  "writeConcernErrors": [],
  "insertedIds": [],
  "nInserted": 0,
  "nUpserted": 0,
  "nMatched": 3,
  "nModified": 3,
  "nRemoved": 0,
  "upserted": [],
  "lastOp": {
    "ts": "6564991738253934601",
    "t": 20
  }
}
Mongoose: tests.find({}, { fields: {} })
[
  {
    "_id": "5b1b89348f3c9e1cdb500699",
    "slno": 1,
    "name": "Item 3",
    "__v": 0
  },
  {
    "_id": "5b1b89348f3c9e1cdb50069a",
    "slno": 2,
    "name": "Item 1",
    "__v": 0
  },
  {
    "_id": "5b1b89348f3c9e1cdb50069b",
    "slno": 3,
    "name": "Item 2",
    "__v": 0
  }
]

That's using syntax which is compatible with NodeJS v6.x

回答2:

A small change in Neil Lunn's answer did the job.

const Model = require('../models/model');

router.post('/update', (req,res) => {

var tempArray=[];

req.body.updates.map(({slno,name}) => {
    tempArray.push({
      updateOne: {
        filter: {slno},
        update: {$set: {name}}
      }
    });
 });

Model.bulkWrite(tempArray).then((result) => {
  //Send resposne
}).catch((err) => {
   // Handle error
});

Thanks to Neil Lunn.