Mongoose, update values in array of objects

Is there a way to update values in an object?

{
  _id: 1,
  name: 'John Smith',
  items: [{
     id: 1,
     name: 'item 1',
     value: 'one'
  },{
     id: 2,
     name: 'item 2',
     value: 'two'
  }]
}

Lets say I want to update the name and value items for item where id = 2;

I have tried the following w/ mongoose:

var update = {name: 'updated item2', value: 'two updated'};
Person.update({'items.id': 2}, {'$set':  {'items.$': update}}, function(err) { ...

Problem with this approach is that it updates/sets the entire object, therefore in this case I lose the id field.

Is there a better way in mongoose to set certain values in an array but leave other values alone?

I have also queried for just the Person:

Person.find({...}, function(err, person) {
  person.items ..... // I might be able to search through all the items here and find item with id 2 then update the values I want and call person.save().
});

You're close; you should use dot notation in your use of the $ update operator to do that:

Person.update({'items.id': 2}, {'$set': {
    'items.$.name': 'updated item2',
    'items.$.value': 'two updated'
}}, function(err) { ...

model.update(
    { _id: 1, "items.id": "2" },
    {
        $set: {
            "items.$.name": "yourValue",
            "items.$.value": "yourvalue",
         }
    }
)

MongoDB Document

There is a mongoose way for doing it.

const itemId = 2;
const query = {
  item._id: itemId 
};
Person.findOne(query).then(doc => {
  item = doc.items.id(itemId );
  item["name"] = "new name";
  item["value"] = "new value";
  doc.save();

  //sent respnse to client
}).catch(err => {
  console.log('Oh! Dark')
});

There is one thing to remember, when you are searching the object in array on the basis of more than one condition then use $elemMatch

Person.update(
   {
     _id: 5,
     grades: { $elemMatch: { grade: { $lte: 90 }, mean: { $gt: 80 } } }
   },
   { $set: { "grades.$.std" : 6 } }
)

here is the docs

For each document, the update operator $set can set multiple values, so rather than replacing the entire object in the items array, you can set the name and value fields of the object individually.

{'$set':  {'items.$.name': update.name , 'items.$.value': update.value}}

Below is an example of how to update the value in the array of objects more dynamically.

Person.findOneAndUpdate({_id: id}, 
{ 
  "$set": {[`items.$[outer].${propertyName}`]: value} 
},
{ 
  "arrayFilters": [{ "outer.id": itemId }]
},
function(err, response) {
  ...
})

Note that by doing it that way, you would be able to update even deeper levels of the nested array by adding additional arrayFilters and positional operator like so:

"$set": {[`items.$[outer].innerItems.$[inner].${propertyName}`]: value} 

"arrayFilters":[{ "outer.id": itemId },{ "inner.id": innerItemId }]

---

More usage can be found in the official docs.

In Mongoose, we can update array value using $set inside dot(.) notation to specific value in following way

db.collection.update({"_id": args._id, "viewData._id": widgetId}, {$set: {"viewData.$.widgetData": widgetDoc.widgetData}})

Having tried other solutions which worked fine, but the pitfall of their answers is that only fields already existing would update adding upsert to it would do nothing, so I came up with this.

 Person.update({'items.id': 2}, {$set: {
    'items': { "item1",  "item2",  "item3",  "item4" } }, {upsert: 
true })

I had similar issues. Here is the cleanest way to do it.

    const personQuery = {
       _id: 1  
    }

    const itemID = 2;

    Person.findOne(personQuery).then(item => {
       const audioIndex = item.items.map(item => item.id).indexOf(itemID);
       item.items[audioIndex].name = 'Name value';
       item.save();
    });

Found this solution using dot-object and it helped me.

import dot from "dot-object";

const user = await User.findByIdAndUpdate(id, { ...dot.dot(req.body) });

I needed to update an array element with dynamic key-value pairs. By mapping the update object to new keys containing the $ update operator, I am no longer bound to know the updated keys of the array element and instead assemble a new update object on the fly.

update = {
  name: "Andy",
  newKey: "new value"
}
new_update = Object.fromEntries(
  Object.entries(update).map(
    ([k, v], i) => ["my_array.$." + k, v]
  )
)
console.log({
  "$set": new_update
})

cleaner solution using findOneAndUpdate

  await Person.findOneAndUpdate(
    { _id: id, 'items.id': 2 },
    {
      $set: {
        'items.$.name': 'updated item2', 
        'items.$.value': 'two updated',
      }
    },
   );

In mongoose we can update, like simple array

user.updateInfoByIndex(0,"test")

User.methods.updateInfoByIndex = function(index, info) ={
    this.arrayField[index]=info
    this.save()
}

update(
    {_id: 1, 'items.id': 2},
    {'$set': {'items.$[]': update}},
    {new: true})

Here is the doc about $[]: https://docs.mongodb.com/manual/reference/operator/update/positional-all/#up._S_[]