如何使用数组中的复杂对象验证猫鼬模式

Question

I am building a schema which has a complex object in an array:

foo:{
   bar:[{
       ItemA:String,
       ItemB:String
   }]
}

I want to add validation to the object in the array so as to check the array size (I want to limit the size of the array to 10).

How would I structure the schema so as to validate that sort of object in the array?

Answer 1

You can do it through validate option in Schema as below

var FooSchema = new Schema({
    foo:{
       bar: {
            type: [{
               ItemA:String,
               ItemB:String
            }],
            validate: [arrlimit, '{PATH} exceeds the limit 10']
        }
    }
});

function arrlimit(arr) {
    return arr && arr.length <= 10;
};

If you add more than 10 items into bar array like

var f = Foo({});
for (var i = 0; i < 12; ++i)
    f.foo.bar.push({ItemA: 'A', ItemB: 'B'});

f.save(function(err) {
    if (err)
        console.log(err);
    else
        console.log('save foo successfully....');
})

Error will come up

{ [ValidationError: Foo validation failed]
  message: 'Foo validation failed',
  name: 'ValidationError',
  errors:
   { 'foo.bar':
      { [ValidatorError: foo.bar exceeds the limit 10]
        properties: [Object],
        message: 'foo.bar exceeds the limit 10',
        name: 'ValidatorError',
        kind: 'user defined',
        path: 'foo.bar',
        value: [Object] } } }