如何使用 angular nodejs express 更新 mongodb 中的数据

Question

I want to update the likes' value with 1.

My MongoDB structure is as follows.

   {"_id":{"$oid":"5f980a66c4b0d52950bdf907"},
    "course_id":"5002",
    "lecture_id":"451",
    "__v":0,
    "created_at":{"$date":"2020-10-27T11:54:14.842Z"},
    "message":[
    {
    "_id":{"$oid":"5f980a84c4b0d52950bdf90a"},
    "from":{
    "userId":"68819","name":"Developer IIRS",
    "avatar":"https://api.adorable.io/avatars/285/811753.png"
    },
    "content":"ok",
    "likes":0,
    "parent_id":null,
    "created_at":{"$date":"2020-10-27T11:54:44.388Z"}
    }
    ]
    }

Here is my code to update value of likes

    router.post('/:lectureId/:courseId/:id', function(req, res, next) {
      let query = {
        lecture_id: req.params.lectureId,
        course_id: req.params.courseId
    
      };
      let update = { $push: { message: { _id: req.params.id,likes: 1 } } }
    
      var options = {
        new: true
      }
      console.log('Liked', query)
    
      Chat.update(query, update, function(err, result) {
        if (err) {
          //res.send(err);
          console.log('err',err );
          return err;
        }
        res.json(result);
      })
    }); 

Its basically adding new document. I am stuck here how can i do this.

Answer 1

  "lecture_id": "451",
  "course_id": "5002"
},
{
  $inc: {
    "message.$[elem].likes": 1
  }
},
{
  new: true,
  arrayFilters: [
    {
      "elem._id": "5f980a84c4b0d52950bdf90a"
    }
  ]
})```

Answer 2

Here is the mongo query.

db.collection.update({
  "lecture_id": "451",
  "course_id": "5002",
  "message._id": "5f980a84c4b0d52950bdf91a"
},
{
  "$inc": {
    "message.$.likes": 1
  }
})

Try it here Mongo Playground

Not an expert in nodejs. Below update statement may work for you.

let update = { $inc: { "message.$.likes": 1 } }