MongoDB - Querying a nested boolean field-CodePudding

I have the following mongoclient query:

db = db.getSiblingDB("test-db");
hosts = db.getCollection("test-collection")
db.hosts.aggregate([
    {$match: {"ip_str": {$in: ["52.217.105.116"]}}}
]);

Which outputs this:

{
    "_id" : ObjectId("..."),
    "ip_str" : "52.217.105.116",
    "data" : [
        {"ssl" : {"cert" : {"expired" : "False"}}}
    ]
}

I'm trying to build the query so it returns a boolean True or False depending on the value of the ssl.cert.expired field. I'm not quite sure how to do this though. I've had a look into the $lookup and $where operators, but am not overly familiar with querying nested objects in Mongo yet.

CodePudding user response：

As the data is an array, in order to get the (first) element of the nested expired, you should work with $arrayElemAt and provide an index as 0 to indicate the first element.

{
  $project: {
    ip_str: 1,
    expired: {
      $arrayElemAt: [
        "$data.ssl.cert.expired",
        0
      ]
    }
  }
}

Demo @ Mongo Playgound