Mongoose: Lean populate doesn't return virtual field

[SuEric]

Description
I'm trying to do combine lean & populate for returning a virtual field. However virtual field name isn't being returned.

Question Schema:

const QuestionSchema = new mongoose.Schema({
  title: {
    type: String,
    required: true,
    trim: true,
  },
  question: {
    type: String,
    required: true,
    trim: true,
  },
  author: {
    type: mongoose.Schema.Types.ObjectId,
    ref: 'User',
    required: true,
  },
...
});

const Question = mongoose.model('Question', QuestionSchema);

User Schema:

const UserSchema = new mongoose.Schema({
  email: {
    type: String,
    unique: true,
    required: true,
    trim: true,
  },
...
});

UserSchema.virtual('name')
  .get(function () {
    if (this.nickname) {
      return this.nickname;
    } else if (this.firstName || this.lastName) {
      return `${this.firstName} ${this.lastName}`;
    } else {
      return this.email.substr(0, this.email.indexOf('@'));
    }
  });

Query (bug is here)

      .find(query)
      .lean()
      .populate('author', {email: 1, name: 1})
      .select('-fraudStatus -entityStatus -__v')
      .then((questions) => {
        if (req.user.type === Constant.user.type.journalist) {
          questions.forEach((question) => {
            question.answers = question.answers.length;
          });
        } else if (req.user.type === Constant.user.type.source) {
          questions.forEach((question) => {
            question.answers = question.answers.find((answer) => answer.author.equals(req.user._id)) ? 1 : 0;
          });
        }
        res.json(questions);
      })
      .catch((err) => {
        next(err);
      });
  }

Steps to reproduce

1. Define schema with virtual field name
2. Do a query with lean & populate virtual field name
3. Check result contain email but not name field

Expected
name should be returned

Actual
name not returned response

[SuEric]

I think this is duplicate #5232 . Please confirm

[vkarpov15]

No, these 2 issues are independent. Using lean() turns off virtuals by design, so lean() means no virtual populate currently. Will add the ability to turn virtuals on with lean() in a future release, this has come up a few times in various contexts.

[vkarpov15]

Should be fixed with 4.11 plus https://github.com/vkarpov15/mongoose-lean-virtuals .

[SuEric]

When will this be released? :)

[vkarpov15]

Planning on releasing 4.11 this week, here's the milestone: https://github.com/Automattic/mongoose/milestone/162 . Work is done, just waiting on some more reviews and final testing.

[shreyawhiz]

How can i turn virtuals on with lean() in mongoose v4.11.1?

[vkarpov15]

@shreyawhiz use the https://www.npmjs.com/package/mongoose-lean-virtuals plugin. I had forgotten to publish it on npm, but it's up now.