"Operation passed in cannot be an array" compass error - but JSON isn't an array

Question

Trying to import simple data (see below), gets me an error "Operation passed in cannot be an array" in Compass 1.29.6

This error makes no sense to me, as the outer object is not an array. Sure, the first object contains an array, but how is this not importable, since it is valid JSON? What is it expecting?

I have checked the documentation for Compass, perused other similar errors, no answers are obvious or relevant enough to help me.

{
   "Name": "root",
   "ID": 0,
   "Children": [{
    "Name": "Chocolates",
    "ID": 1,
    "ParentID": 0
   }]
}

Hoff

No problem to insert it to Robo-3T – Tobitobiah

Try: db.getCollection(<name>).insert({ "Name": "root", "ID": 0, "Children": [{ "Name": "Chocolates", "ID": 1, "ParentID": 0 }] }) – Tobitobiah

So Compass and MongoDB require imported JSON data to be arrays instead of objects? The standard JSON empty object is {}, so it would be input as [{}] or as []? – Nomen

Answer 1

I am a bit late but try to wrap your object into array like

[{
   "Name": "root",
   "ID": 0,
   "Children": [{
    "Name": "Chocolates",
    "ID": 1,
    "ParentID": 0
   }]
}]

it will work

Messuage

Hey thanks. This saved me. It looks like the data I am getting from my sources is in pure JSON but what compass expects is a list of documents. So for my data I had to remove the outside wrapper object on my data but leave the list of objects inside it so that the "outermost structure" is a list. – Goings

Answer 2

MongoDB Compass accepts documents in unformatted json structure, I used http://json.dylansweb.com/ to un-format the json and it worked fine in Compass.

Ligan

Compass processed my formatted JSON just fine. Formatted vs. unformatted doesn't really make sense, since whitespace is irrelevant in JSON. – Goings

Answer 3

This has been an open issue on github for over 4 years now with no real solution from compass. Every suggestion is pretty hacky and the only real solutions seem to be to not use Compass https://github.com/mongo-express/mongo-express/issues/433

Devorahdevore