Improve mongoose validation error handling

问题

I have the following schema with required validations:

var mongoose = require("mongoose");
var validator = require("validator");

var userSchema = new mongoose.Schema(
  {
    email: {
      type: String,
      required: [true, "Email is a required field"],
      trim: true,
      lowercase: true,
      unique: true,
      validate(value) {
        if (!validator.isEmail(value)) {
          throw new Error("Please enter a valid E-mail!");
        }
      },
    },
    password: {
      type: String,
      required: [true, "Password is a required field"],
      validate(value) {
        if (!validator.isLength(value, { min: 6, max: 1000 })) {
          throw Error("Length of the password should be between 6-1000");
        }

        if (value.toLowerCase().includes("password")) {
          throw Error(
            'The password should not contain the keyword "password"!'
          );
        }
      },
    },
  },
  {
    timestamps: true,
  }
);

var User = mongoose.model('User', userSchema);

I pass the email and password through a form by sending post request using the following route:

router.post("/user", async (req, res) => {
  try {
    var user = new User(req.body);
    await user.save();
    res.status(200).send(user);
  } catch (error) {
    res.status(400).send(error);
  }
});

module.exports = mongoose.model("User", user);

Whenever I enter a field against the validation rules, I get a very long error message, which is obvious. But now, I want to improve the error handling so that it gets easy to interpret for the users. Rather than redirecting to a generic error page, how can I redirect to the same signup page and display the flash messages near the incorrect fields telling about the error? And also on success, something similar should be done, like a green flash message on the top.

I am using ejs for my signup pages.

回答1:

In the catch block, you can check if the error is a mongoose validation error, and dynamically create an error object like this:

router.post("/user", async (req, res) => {
  try {
    var user = new User(req.body);
    await user.save();
    res.status(200).send(user);
  } catch (error) {
    if (error.name === "ValidationError") {
      let errors = {};

      Object.keys(error.errors).forEach((key) => {
        errors[key] = error.errors[key].message;
      });

      return res.status(400).send(errors);
    }
    res.status(500).send("Something went wrong");
  }
});

When we send a request body like this:

{
   "email": "test",
   "password": "abc"
}

Response will be:

{
    "email": "Please enter a valid E-mail!",
    "password": "Length of the password should be between 6-1000"
}

回答2:

you can use validator like this instead of throwing an error :

password:{
    type:String,
    required:[true, "Password is a required field"],

validate: {
  validator: validator.isLength(value,{min:6,max:1000}),
  message: "Length of the password should be between 6-1000"
}
    }

回答3:

you can send

res.status(400).send(error.message);

instead of :

res.status(400).send(error);

and you should make some changes in Schema also.

validate(value){
            if (!validator.isEmail(value)) {
                throw new Error("Please enter a valid E-mail!");
            }
        }

with

validate: [validator.isEmail, "Please enter a valid E-mail!" ]

and for password:

minlength: 6,
maxlength:1000,
validate:{
validator: function(el){
return el.toLowerCase() !== "password"
}
message: 'The password should not contain the keyword "password"!'
}

来源：https://stackoverflow.com/questions/61056021/improve-mongoose-validation-error-handling