I apologize for my poor way of explaining my issue. I am trying to update my schema's notes and assignmentHistory fields. I have no issues updating notes field but with the assignmentHistory field what I am trying to do is append values to the array only if the assingedTo value has changed from it's last value or is not empty only then $push to assignmentHistory array, otherwise don't add anything to assigmentHistory array. Basically, how do I prevent $push not add anything to the assignmentHistory array, not even empty object with _id field? Below is snippet of my code
const RequestSchema = new Schema(
{
title: { type: String, required: true, max: 32, min: 6 },
priority: { type: String, emum: ["low", "medium", "high"] },
notes: [
{
commentNotes: {
comment: { type: String, max: 200 },
commentBy: { type: Schema.Types.ObjectId, ref: "User" },
commentDate: { type: Date },
}
]
assignedTo: { type: Schema.Types.ObjectId, ref: "User" },
assigmentHistory: [
{
techName: { type: Schema.Types.ObjectId, ref: "User" },
assignedDate: { type: Date },
}
]
}
let noteObj={};
let techobj={};
await RequestModel.findOneAndUpdate(
{ _id },
{
$push: {
notes: [noteObj],
assignmentHistory:[techobj]
},
},
{ new: true }
);
In order to only push an element in an array if the value is not present yet, you can use $addToSet. See this example on mongoplayground. Regarding handling the empty object - I'd just do it on the client side and dynamically build the query. So something like:
const addToSetObj = {};
if(!isEmpty(noteObj)) { // use one of the method for isEmpty described here https://stackoverflow.com/q/679915/3761628
pushObj.notes = noteObj;
}
if(!isEmpty(techObj)) {
pushObj.assignmentHistory = techObj;
}
await RequestModel.findOneAndUpdate(
{ _id },
{
$addToSet: addToSetObj
},
{ new: true }
);
I do have a work around but would like a more professional way to avoid adding empty objects to the array field.
Basically, I only wanted to push an object to assigmentHistory array field of my schema if assignedTo variable was true. Good Programming doesn't recommend using same code twice, but in my case I have used the findoneAndUpdate query twice in the if and else condition. Please feel free to optimize it. All I want is when assignedTo variable is false , then $addToSet not add an empty object in the assignmentHistory array field.
if (
assignedTo &&
assignedTo.toString() !== oldRequest.assignedTo.toString()
) {
await RequestModel.findOneAndUpdate(
{ _id },
{
$set: requestFields,
$push: {
notes: [noteObj],
},
$addToSet: { assigmentHistory: [newtech_info_object] },
},
{ new: true }
);
} else {
await RequestModel.findOneAndUpdate(
{ _id },
{
$set: requestFields,
$push: {
notes: [noteObj],
},
},
{ new: true }
);
}