高级结构

¥Advanced Schemas

使用 loadClass() 从 ES6 类创建

¥Creating from ES6 Classes Using loadClass()

Mongoose 允许从 ES6 类 创建结构。loadClass() 函数允许你从 ES6 类中提取方法、静态和虚函数。类方法映射到结构方法，静态方法映射到结构静态，getter/setter 映射到虚拟方法。

¥Mongoose allows creating schemas from ES6 classes. The loadClass() function lets you pull in methods, statics, and virtuals from an ES6 class. A class method maps to a schema method, a static method maps to a schema static, and getters/setters map to virtuals.

const schema = new Schema({ firstName: String, lastName: String });

class HumanClass {
  get fullName() {
    return 'My name';
  }
}

class PersonClass extends HumanClass {
  // `fullName` becomes a virtual
  get fullName() {
    return `${super.fullName} is ${this.firstName} ${this.lastName}`;
  }

  set fullName(v) {
    const firstSpace = v.indexOf(' ');
    this.firstName = v.split(' ')[0];
    this.lastName = firstSpace === -1 ? '' : v.substring(firstSpace + 1);
  }

  // `getFullName()` becomes a document method
  getFullName() {
    return `${this.firstName} ${this.lastName}`;
  }

  // `findByFullName()` becomes a static
  static findByFullName(name) {
    const firstSpace = name.indexOf(' ');
    const firstName = name.split(' ')[0];
    const lastName = firstSpace === -1 ? '' : name.substring(firstSpace + 1);
    return this.findOne({ firstName, lastName });
  }
}

schema.loadClass(PersonClass);
const Person = db.model('Person', schema);

const doc = await Person.create({
  firstName: 'Jon',
  lastName: 'Snow'
});

assert.equal(doc.fullName, 'My name is Jon Snow');
doc.fullName = 'Jon Stark';
assert.equal(doc.firstName, 'Jon');
assert.equal(doc.lastName, 'Stark');
const foundPerson = await Person.findByFullName('Jon Snow');

assert.equal(foundPerson.fullName, 'My name is Jon Snow');