My db schema looks like that:
[
{
title: {
de: "Test",
en: "test"
},
infos: [
{
label: {
de: "Test",
en: "test"
},
data: [
{
label: {
de: "Test",
en: "test"
}
},
],
}
],
}
]
If I use $project in model.aggregate([]) everything is working fine for objects, so it results in:
title: 'Test' when using following projection:
{title: `$title.de`,}
but for arrays of objects, it just merges all objects in an array like that:
"infos": [
{
"label": [
"Preparation",
"Important"
]
}
]
when using this projection:
'infos.label': `$infos.label.de`
Same for the nested array.
But the result should look like that:
{
infos: [
{
label: 'Test',
data: [
{
label: 'Test'
},
],
}
]
}
Does someone has an idea how to archive something like that?
CodePudding user response：
You should just use $map to iterate over the array and change it accordingly, like so:
db.collection.aggregate([
{
$project: {
title: "$title.de",
infos: {
$map: {
input: "$infos",
in: {
$mergeObjects: [
"$$this",
{
label: "$$this.label.de"
}
]
}
}
}
}
}
])