如何在 mongoose 中更新数组中的嵌入文档，其中操作应该是原子的，应该更新最新的文档并返回更新的文档？

Question

Currently working on node.js and MongoDB with mongoose.

//Document in mongoDB
{
  name: 'first',
  _id: '1000'
  phases: [{
      _id: 1,
      phaseName: 'phase1',
      stories: [{
          _id: s1,
          sname: 'sfirst'
        },
        {
          _id: s2,
          sname: 'ssecond'
        },
        {
          _id: s3,
          sname: 'sthird'
        }
      ],

    },
    {
      _id: 2,
      phaseName: 'phase2',
      stories: [{
          _id: s1,
          sname: 'sfirst'
        },
        {
          _id: s2,
          sname: 'ssecond'
        },
        {
          _id: s3,
          sname: 'sthird'
        }
      ],

    }
  ],
}

All I have is

1. id=1000 (to find this document in mongodb)
2. phaseId=1 and remstoryId=s2 (ie delete s2 from stories from phase with id 1)
3. phaseId=2, storyId={ _id: s4, sname: fourth}, position: 1 (add story in stories at index 1 in phase 2)

Main requirement is this operation should be

1. Atomic
2. No other user can perform operation on this same document while performing above operation. I mean lock this document.

I can we can do this operation using findOne() and save()

Model.findOne({
  id
}, (err, plan) => {
  if (!err) {

    //REMOVE THE STORY FROM PHASE
    const phase = plan.phases.find((phase) => phase._id === delPhaseID);
    phase.stories = phase.stories.filter((story) => story._id !== delStoryId);

    //ADD STORY IN STORIES
    const addPhase = plan.phases.find((phase) => phase._id === addPhaseID);
    addPhase.stories.splice(pos, 0, story);

    //SAVE PLAN
    plan.save((err, doc) => {
       if(!err)
         console.log(doc) // UPDATED DOCUMENT
       });
  }
})

but this operation is not atomic as per below image taken from masteringjs . How can we solve this problem

Answer 1

You can try findOneAndUpdate() with arrayFilters ,

• $pull to remove in p1 id's stories is s1
• $push to specific position for p2 use $position
• new: true to return updated document

Model.findOneAndUpdate(
    { _id: "1000" },
    {
        $pull: {
            "phases.$[p1].stories": {
                _id: "s1"
            }
        },
        $push: {
            "phases.$[p2].stories": {
                $each: [{
                    _id: "s4",
                    sname: "fourth"
                }],
                $position: 1
            }
        }
    },
    {
        arrayFilters: [
            { "p1._id": 1 },
            { "p2._id": 2 }
        ],
        new: true
    }
)