mongoose find and update removes the other fields - mongodb

Question

I have schema like this:
this.schema = new Schema({
userEmail: String
environments: [
{
envId: String,
appPreference: String,
language: String,
timeZone: String,
summaryNotificationSchedule: {
timeOfTheDay: String
}
}
]
});
Update request:
{
"envId": "u2",
"appPreference": "put2",
"timeZone": "gmt",
"summaryNotificationSchedule.timeOfTheDay": "32400",
}
As you can see, I am not sending "language": "abc", in the update request and in the result I see the language field is removed. I want to update the fields but not remove the other fields
Mongoose find and update call:
await this.model.findOneAndUpdate({ userEmail, 'environments.envId': envId }, { $set: { 'environments.$': setPreferenceFields } }, { new: true });

Answer 1

You can create update object from your request first:
let request = {
"envId": "u2",
"appPreference": "put2",
"timeZone": "gmt",
"summaryNotificationSchedule.timeOfTheDay": "32400",
};
let update = Object.keys(request).reduce((acc, cur) => {
acc[`environments.$.${cur}`] = request[cur];
return acc;
}, {})
console.log(update);
Then pass it to the update:
await this.model.findOneAndUpdate({ userEmail, 'environments.envId': envId }, { $set: update }, { new: true });

Answer 2

You have to specify property with parent key name of an array, it should be like this way,
await this.model.findOneAndUpdate(
{
userEmail,
'environments.envId': envId
},
{
$set: {
'environments.$.envId': "u2",
'environments.$.appPreference': "put2",
'environments.$.timeZone': "gmt",
'environments.$.summaryNotificationSchedule.timeOfTheDay': "32400"
}
},
{ new: true }
)
Another option, update with aggregation pipeline start from MongoDB v4.2, this little lengthy process then above method,
$map to iterate loop of environments array
$cond check condition if envId is equal to matching envId then merge objects update objects and current objects using $mergeObjects otherwise return current object
await this.model.findOneAndUpdate(
{ userEmail },
[
{
$set: {
environments: {
$map: {
input: "$environments",
in: {
$cond: [
{$eq: ["$$this.envId", envId]}, // add update id
{
$mergeObjects: [
"$$this",
setPreferenceFields // your update fields
]
},
"$$this"
]
}
}
}
}
}
],
{new: true}
)