Well, I have used MongoDB in a while but I don't know how to handle this situation.

The scenario is: I have data inserted in MongoDB. I have exported the data in JSON format, and it is something like:

[
  {
    "_id": { "$oid": "60ff324f41c4d5b96054390d" },
    "field": {
      "due_date": { "$date": "2021-11-03T00:09:18.271Z" }
    }
  }
]

You can see that :

• _id is { "$oid": "60ff324f41c4d5b96054390d" } and
• date is { "$date": "2021-11-03T00:09:18.271Z" }.

So, the problem is trying to insert in another DB using Mongoose. I want to test some funcionality isolated so I wan't these values in other environment, so I have used insertMany() with the JSON previously exported.

(Maybe there is a more elegant way to import a JSON file but is only for testing purposes)

await model.insertMany(JSON.parse(fs.readFileSync('./data.json').toString()))

But the problem is here: It throws an error because my schema says that _id is an ObjectId and due_date is a Date object but they are actually read as objects: {$oid: ""} and {$date: ""}

ValidationError: model validation failed: _id: Cast to ObjectId failed for value "{ '$oid': '60ff324f41c4d5b96054390d' }" (type Object) at path "_id", field.due_date: Cast to date failed for value "{ '$date': '2021-11-03T00:09:18.271Z' }" (type Object) at path "field.due_date"

So the question is: Is there any way to cast the $oid and $date objects using mongoose while inserting?

Also, I have managed to insert the values using a very ugly script iterating over each value and checking if the object is $oid or $date and modifying the values... but it works.

So the question is not: "Is there a workaround to do this?" but "Is there a way to do it directly with mongoose functions as insertMany and casted automatically?"

Thanks.

CodePudding user response：

The {"$oid": ...} and {"$date":...} constructs are MongoDB extended JSON notation, since JSON does not have any type for Date or ObjectId.

In order to insert those values, you will need to use a JSON parser that knows about this extended format.

One possibility is the json_util that is included with bson.

Or you can use mongoimport to read the JSON file and do the inserts for you.