mongoDb $in with aggregate query

Question

How do I write an $in query along with aggregate in mongoDB? I want to write an equivalent mongoDB query for the SQL below

SELECT name,count(something) from collection1
where name in (<<list of Array>>) and cond1 = 'false'
group by name

Answer 1

The equivalent mongo query follows:

db.collection1.aggregate([
    { "$match": { 
        "name": { "$in": arrayList },
        "cond1": "false"
    } }, 
    { "$group": {
        "_id": "$name",
        "count": { "$sum": "$something" }
    } }
])

Answer 2

Suppose you have an Schema with field tags

{
 tags: ['banana', 'apple', 'orange']
}

and you want find out apple inside tags with aggregate function then

const keywords = "apple"; // req.body.keywords

const filter =  { $match : { tags: {$in : [keywords] } }}

Schema.aggregate(filter).then(result=>{
 // You can do what you want with result
})