Minimongo nested query embed documents

i want to search into an embed document in mongodb and return only what i'm looking for. Here's the document:

"_id" : "yH8HmCPz6H6E8Hinq",
"between" : [
    "4bgdLrztpqgwAkZP4",
    "9jZhXHjAkoY7mmX7B"
],
"messages" : [
    {
        "content" : "fdsqf",
        "user" : "4bgdLrztpqgwAkZP4",
        "created_at" : ISODate("2016-11-17T23:13:59.659Z"),
        "isSeen" : false,
        "sender" : "John doe",
        "receiver" : "Elen doe"
    },
    {
        "content" : "test",
        "user" : "9jZhXHjAkoY7mmX7B",
        "created_at" : ISODate("2016-11-20T11:42:42.893Z"),
        "isSeen" : false,
        "sender" : "Elen doe",
        "receiver" : "John doe"
    }
]

All what i want to have is "messages.isSeen" equals to false and receiver isn't Meteor.user().username.

And finally how to update that field to become true.

Hope someone can help ! Thanks in advance !

You need to include the _id in the query and $set in the update.

let id = "yH8HmCPz6H6E8Hinq";
let username = Meteor.user().username;
let query = { _id: id, messages: { $elemMatch: { isSeen: false, receiver: { $ne: username }}}};
Chat.update(query,{ $set: { "messages.$.isSeen": true }});