.id returns string while ._id returns object. is this a bug?

[adamz123]

In the following function, test1 is a string because the virtual path runs through a different codeset and runs the toString() function, whereas test2 is an object with the 'id' set to the hex id. The console.log will produce the same result since console.log will call the .toString function in the object. However, I was under the impression .id and ._id were supposed to be the same thing. Which one am I supposed to be using or is this a bug?

function createSegment(options, callback){
var location = options.location;
var newSegment = new Segment({coordinates: new Array(location)});
newSegment.save(function(err){
if(err) {callback(err); return;}
debugger;
var test1 = newSegment.id;
var test2 = newSegment._id;
console.log(newSegment.id);
console.log(newSegment._id);
callback(null, newSegment.id);
});
}

[donpark]

_id is an instance of ObjectId which is native-mongodb-driver's representation of binary structure MongoDB uses.

id is convenience method for retrieving string representation of _id.

What I'm wondering is whether id really got added to Mongoose since it might conflict with my own impl. of id.

[aheckmann]

yes @donpark is correct. ObjectIds contain the raw MongoDB binary and don't work with templating so we provide the id convenience method to convert them to hexstrings. Mongoose also transparently casts these hexstrings back to ObjectIds for you when querying / creating objects etc.

This is the flow we are making simpler:

MongoDB -> ObjectId -> cast toHexString -> form -> submit -> cast from hexString -> ObjectId -> MongoDB

[c4milo]

wait, does it mean that we can't use a property "id" in our Schemas? I'm using my own "id" implementation as well

[aheckmann]

@c4milo you can use your own id. We only add it if you haven't.

[c4milo]

nice, tks

[technotronic12]

@aheckmann I am also using my own id (a string guid). recently I started receiving this error: Named property 'id' of types 'IMaintenance' and 'Document' are not identical. Any idea what might cause it? Is it related to the current issue?