Mongo Mongoose Objects Weird Properties Can't Access

Yep. I'm all about search engine titles this week.

In my new Mongo/mongoose world, I've exposed myself ot a ton of information, tutorials, explanations, examples, you name it and there is a HUGE thing that no one mentions.

Perhaps I'm an idiot or maybe the fact that I work entirely alone means that I am not privy to common knowledge so common that no one needs to say it but, I'm saying it now:

Mongoose does not create nice Javascript objects. When you do a find, you get something that will console.dir() and look like something you recognize. It is a false appearance. It is some nasty Mongo thing. Eg,...

I had an object that, viewed with my general purpose display program, looks like this:

Doesn't look like it should be a problem. Addressing it as...

var item=recipient[0][0];

recipient[0] gave me the first array element, an object.

recipient[0][0] attempted to to address the object containing the email address and came back undefined.

Nothing I could do gave me the email address. It was insane.

Turns out that I could google the answer pretty easily once I realized what was going on but only after tearing my hair out because no one mentioned that mongoose produces bizarre data structures.

The answer is (drum roll, please)...


as in...

query.lean().exec(wrapCallback(callback)); //this produces a plain, Javascript object

as compared to

query.exec(wrapCallback(callback)); //this produces a mongoose object from hell

Obviously, if you are doing your processing in a model, you might really like the benefits of using the mongoose data type. I bet there are a TON of them but, if you are trying to construct a test, as I was, or send it to a web page, like I plan to do, you are going to want something that acts like a civilized citizen, not some rogue toxic waste factory.

But, I wouldn't have minded at all if somewhere in the mongoose quick start and documentation they had said, "The output of find() must be accessed with mongoose utilities unless you add the lean() function to convert it to plain Javascript."

Maybe you got to this note before you actually ruined yourself. Or, maybe you, like everyone else on earth, already know.