mongodb Mongoose：如何将架构字段设置为 ID？
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Mongoose: how to set a schema-field to be the ID?
提问by Geert-Jan
Given the following schema:
鉴于以下架构：
var UserSchema = new Schema({
, email : { type: String }
, passwordHash : { type: String }
, roles : { type: [String] }
});
I'd like emailto be the key.
How can I define this?
我想email成为关键。我该如何定义？
I could do:
我可以：
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 _idinstead of emailbut that doesn't feel clean to me.
所以 MongoDB 会将它识别为 id 字段，并调整我的代码以引用_id而不是，email但这对我来说并不干净。
Anyone?
任何人？
回答by JohnnyHK
Since you're using Mongoose, one option is to use the email string as the _idfield and then add a virtual fieldnamed emailthat returns the _idto clean up the code that uses the email.
由于您使用的是 Mongoose，因此一种选择是使用电子邮件字符串作为_id字段，然后添加一个名为返回的虚拟字段以清理使用电子邮件的代码。email_id
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: trueoption in the toObject()or toJSON()call:
请注意，将 Mongoose 文档转换为纯 JS 对象或 JSON 字符串时，默认情况下不包含虚拟字段。要包含它，您必须virtuals: true在toObject()ortoJSON()调用中设置选项：
var obj = doc.toObject({ virtuals: true });
var json = doc.toJSON({ virtuals: true });
