Remove mongo array if nested array is empty - php

Question

i have got a mongo array , in which i want to remove the whole block , if the nested array of that block is empty
I have attached the array below
{
"_id" : ObjectId("5b17b991c440782b5a218cd1"),
"vendor_view_id" : 741733,
"product" : [
{
"id" : ObjectId("5b86546540c1c414543e4333"),
"vendor_user_id" : ObjectId("5b17b992c440782b5a218cd2"),
"product_type_id" : ObjectId("5ae8348b7ae0d9538e45ab46"),
"condition_id" : [ ],
"shipping_cost" : 100,
"date_added" : "2018-08-29-08-08-05",
"date_status_change" : "2018-08-29-08-08-05",
"status" : 0
},
{
"id" : ObjectId("5b8654ba40c1c4145d1f5473"),
"vendor_user_id" : ObjectId("5b17b992c440782b5a218cd2"),
"product_type_id" : ObjectId("5ae834b17ae0d9538e45ab48"),
"condition_id" : [ ],
"shipping_cost" : 100,
"date_added" : "2018-08-29-08-09-30",
"date_status_change" : "2018-08-29-08-09-30",
"status" : 0
},
{
"id" : ObjectId("5b8655a840c1c415080b0a33"),
"vendor_user_id" : ObjectId("5b17b992c440782b5a218cd2"),
"product_type_id" : ObjectId("5ae834a67ae0d9538e45ab47"),
"condition_id" : [
{
"_id" : ObjectId("5ae977da7ff1706f3b7dc47a"),
"status" : 0,
"date_added" : "2018-08-29-08-13-28"
}
],
"shipping_cost" : 100,
"date_added" : "2018-08-29-08-13-28",
"date_status_change" : "2018-08-29-08-13-28",
"status" : 0
}
]
}
I would like to delete the array block where product.condition_id is empty
So far i have tried this
$this->collection_name->collection->updateOne([
'_id' => $vendor_id,
],
[
'$unset' =>
[
'product.$.condition_id' =>
[
'$size'=>0,
]
]
])
EDIT 1:
db.collection_name.collection({_id : ObjectId('5b17b991c440782b5a218cd1'),
"product.condition_id.$":{ "$exists": false }},
{ "$unset": { "product.$": "" }});
still not working

Answer 1

db.collection_name.update(
{},
{$pull : {product : {condition_id : {$size : 0} }}},
{ multi: true } // multi : true will updates multiple documents that meet the query criteria
)
if condition_id array is empty pull the document.
Output:
{
"_id" : ObjectId("5b17b991c440782b5a218cd1"),
"vendor_view_id" : 741733,
"product" : [
{
"id" : ObjectId("5b8655a840c1c415080b0a33"),
"vendor_user_id" : ObjectId("5b17b992c440782b5a218cd2"),
"product_type_id" : ObjectId("5ae834a67ae0d9538e45ab47"),
"condition_id" : [
{
"_id" : ObjectId("5ae977da7ff1706f3b7dc47a"),
"status" : 0,
"date_added" : "2018-08-29-08-13-28"
}
],
"shipping_cost" : 100,
"date_added" : "2018-08-29-08-13-28",
"date_status_change" : "2018-08-29-08-13-28",
"status" : 0
}
]
}

Answer 2

You can transform your json to PHP array json_decode($json) so you'll be able to process it before it turn into json after.
json_encode($arr)
Note that you can check the depth of the array in your case to see if product.condition_id is empty.