Question

Given the following schema:

var UserSchema = new Schema({
   , email   :  { type: String }
   , passwordHash   :  { type: String }
   , roles  :  { type: [String] }
});

I’d like email to be the key.
How can I define this?

I could do:

var UserSchema = new Schema({
       , _id:  { type: String }
       , passwordHash   :  { type: String }
       , roles  :  { type: [String] }
    });

so MongoDB would recognize it as the id-field, and adapt my code to refer to _id instead of email but that doesn’t feel clean to me.

Anyone?

Answer 1

Since you’re using Mongoose, one option is to use the email string as the _id field and then add a virtual field named email that returns the _id to clean up the code that uses the email.

var userSchema = new Schema({
    _id: {type: String},
    passwordHash: {type: String},
    roles: {type: [String]}
});

userSchema.virtual('email').get(function() {
    return this._id;
});

var User = mongoose.model('User', userSchema);

User.findOne(function(err, doc) {
    console.log(doc.email);
});

Note that a virtual field is not included by default when converting a Mongoose doc to a plain JS object or JSON string. To include it you have to set the virtuals: true option in the toObject() or toJSON() call:

var obj = doc.toObject({ virtuals: true });
var json = doc.toJSON({ virtuals: true });