virtual path on array

[cncolder]

in mongose guild doc there is a cool example. define .full virtual on sub documents name: {first:String, last:String}. then get virtual value by name.full.

but if i define virtual on array like this:

var schema = new Schema({
  nums: [Number]
});
schema.virtual('nums.odd').get(...).

i cannot get it by dot path nums.odd. only write like this model.get('nums.odd').

is there a way to fix this?
i'm running mongoose@3.9.3

[vkarpov15]

That's weird, that should work in theory. I'll investigate.

[cncolder]

maybe my fault.
only object path can define virtual append with dot.
i don't know how mongoose do that. define a real property on that object? or intercept invoke on schema level?

here is some test code:

  describe('gh-2306', function () {
    it('allow define virtual on non-object path', function () {
      var db = start();
      var schema = new mongoose.Schema({ num: Number, str: String, nums: [Number] });
      schema.virtual('num.power').get(function () {
        return this.num * this.num;
      });
      schema.virtual('str.upper').get(function () {
        return this.str.toUpperCase();
      });
      schema.virtual('nums.last').get(function () {
        return this.nums[this.nums.length - 1];
      });
      var M = db.model('gh2306', schema);
      var m = new M({ num: 2, str: 'a', nums: [1,2,3] });

      assert.equal(m.num.power, 4);
      assert.equal(m.str.upper, 'A');
      assert.equal(m.nums.last, 3);
    });
  });

[shrayolacrayon]

There is no good way to support this right now because getters and setters do not go through the . operator and virtuals are defined in the document level.

You can access the virtuals in the test above as m.get('num.power').

[danielmahon]

+1

[vkarpov15]

We can't support schema.virtual('str.upper') because you can't define getters on primitive values in JavaScript, but schema.virtual('nums.last') and schema.virtual('nums.odd') are possible. We put in PR #14955 to add that feature.