How to use 'like in mongodb' in JavaScript

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public async like(param: any): Promise {
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  const { id: _id } = param
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  const userId = _.get(this.currentUser, '_id')
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  const doc = await this.model.findById(_id)
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  const { likes, dislikes } = doc
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  // can not both like and dislike, use ObjectId.equals to compare
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  if (_.findIndex(dislikes, oid => userId.equals(oid)) !== -1) return doc
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  // already liked, will unlike, use ObjectId.equals to compare
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  if (_.findIndex(likes, oid => userId.equals(oid)) !== -1) {
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    await this.model.findOneAndUpdate(
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      { _id },
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      {
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        $pull: { likes: userId },
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        $inc: { likesNum: -1, activeness: -1 }
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      }
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    )
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  } else {
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    // not like yet, will like it
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    await this.model.findOneAndUpdate(
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      { _id },
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      {
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        $push: { likes: userId },
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        $inc: { likesNum: 1, activeness: 1 }
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      }
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    )
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  }
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  return this.model.findById(_id)
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}

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async function likeATopic (topicId) {
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  console.log(topicId);
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  const topic = await TopicModel.findOneAndUpdate({_id: topicId}, {$inc:{likes:1}}, {new: true, fields: {likes:1}})
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  return topic.likes
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}