SubDocument updates in mongodb using node - node.js

Question

I have collection structure like this.
application_data: {
name : A,
site : B,
location : [
{ key1 : value1, key2 : value2},
{ key3 : value3, key4 : value4}
]
}
Now I want to add a another array to "location" as a sub document so that my location becomes
location : [
{ key1 : value1, key2 : value2},
{ key3 : value3, key4 : value4, key5 :[{subkey1:subvalue1, subkey2:subvalue2}]}
]
I tried $push & $addToSet which did not help me. Can somebody help me?
Helpful if you explain an example using nodejs.

Answer 1

What you'r actually trying to do is to add new field to an existing subdocument. You can do it using $set and positional operator $:
db.applications.update({
name: 'A', // querying for parent document
'location.key3': 'value3' // querying for an exact subdocument to add new field to
}, {
$set: {
'location.$.key5': [{
subkey1: 'subvalue1',
subkey2: 'subvalue2'
}]
}
})
You can achieve the same result using $push or $addToSet, which is better if you want to add more than one subsubdocument to 'location.key5':
db.applications.update({
name: 'A',
'location.key3': 'value3'
}, {
$push: {
'location.$.key5': {
subkey1: 'subvalue1',
subkey2: 'subvalue2'
}
}
})
or
db.applications.update({
name: 'A',
'location.key3': 'value3'
}, {
$addToSet: {
'location.$.key5': {
subkey1: 'subvalue1',
subkey2: 'subvalue2'
}
}
})
See Update Documents in an Array for more info.