Mongoose find and update nested document - mongodb

Question

I am trying to find and update a sub document under another sub document. I am not getting the result as I expect. This is what I currently have setup:
const SiteSchema = new mongoose.Schema({
domain: { type: String, required: true },
keywords: [],
campaigns: [
{
campaign: {
type: mongoose.Schema.Types.ObjectId,
ref: "Campaign",
},
responses: [
{
message: { type: String },
asking_fee: { type: Number },
date: { type: Date },
},
],
}],
})
I would like to find and edit a particular response. Here is the code I have now. I am new to mongoose and MongoDB.
const site = await Site.findOneAndUpdate({
"campaigns.responses._id": responseId, // will it fetch the response ?
}, {
$set: { // I am struggling with the following
"campaigns.$.responses.message": message,
"campaigns.$.responses.asking_price": asking_price,
"campaigns.$.responses.date": date,
},
}
);

Answer 1

If you don't have campaigns.campaign id then you have to use update with aggregation pipeline starting from MongoDB 4.2,
$set to update campaigns field, $map to iterate loop of campaigns array, $map to iterate loop of campaigns.responses array and check condition if responseId match then return updateFields otherwise return old fields and merge with current object using $mergeObjects
let responseId = 1;
let updateFields = {
message: "new message",
asking_fee: 10,
date: new Date()
};
const site = await Site.findOneAndUpdate(
{ "campaigns.responses._id": responseId },
[{
$set: {
campaigns: {
$map: {
input: "$campaigns",
in: {
$mergeObjects: [
"$$this",
{
responses: {
$map: {
input: "$$this.responses",
in: {
$mergeObjects: [
"$$this",
{
$cond: [
{ $eq: ["$$this._id", responseId] },
updateFields,
"$$this"
]
}
]
}
}
}
}
]
}
}
}
}
}]
)
Playground
Second option if you have campaigns.campaign id then you can use $[<identifier>] arrayFilters,
let campaign = 1;
let responseId = 1;
let updateFields = {
message: "new message",
asking_fee: 10,
date: new Date()
};
const site = await Site.findOneAndUpdate({
"campaigns.campaign": campaign,
"campaigns.responses._id": responseId
},
{
$set: {
"campaigns.$[parent].responses.$[child]": updateFields
}
},
{
arrayFilters: [
{ "child._id": responseId },
{ "parent.campaign": campaign }
]
})
Playground