mongoose do not return saved document in callback

问题

I am trying to save a new record using mongoose. I am not getting the saved document in the callback.

 app.post("/register",(req,res) => {
    let userData = req.body;
    let user = new User(userData)
    user.save().then((err,doc) => {
        res.json({"success":true,"data":doc});
        console.log(doc);
    })    
});

I am getting doc:1. While I should get the whole document. Please help me.

  "dependencies": {
    "body-parser": "^1.18.2",
    "crypto-js": "^3.1.9-1",
    "express": "^4.15.5",
    "mongoose": "^4.11.13"
  }

回答1:

You're using promises, then callback provides only one parameter - result of asynchronous call. To catch error, catch callback should be used:

app.post("/register", (req, res) => {
    let userData = req.body;
    let user = new User(userData);
    user
      .save()
      .then(doc => {
        console.log(doc);
        res.json({ success: true, data: doc });
      })
      .catch(err => {
        console.log(err);
        res.status(500).send({ error: err });
      });
});

来源：https://stackoverflow.com/questions/46569248/mongoose-do-not-return-saved-document-in-callback