Mongoose pre-validation hook

mongoose-pre-validation-hook.js

"use strict";
const mongoose = require('mongoose');

const thingWithNameSchema = mongoose.Schema({
    name: String,
});
thingWithNameSchema.pre('validate', (next) => {
    console.log(this);
    console.log(this.name);
    next();
});
const ThingWithName = mongoose.model('ThingWithName', thingWithNameSchema);

const thing = new ThingWithName({ name: 'Namers namer name name' });

thing.validate()
.then(() => console.log('done'))
.catch(() => console.log('error'));

// Output:
// {}
// undefined
// done

Solution: Don't use an arrow function, use function (next) instead. Arrow functions don't have their own this.