How can I refer to the schema I was trying to save in nestjs/mongoose? - mongodb

Question

I am trying to encrypt some passwords and get its salt before saving my model to mongoose in Nestjs, but simply using this to refer to the schema itself doesn't yield any results as it refers to the UserSchemaProvider object itself, instead of the current model I'm trying to save.
My schema provider:
export const UserSchemaProvider = {
name: 'User',
useFactory: (): mongoose.Model<User> => {
const UserSchema = new mongoose.Schema({
name: { type: String, required: true },
email: { type: String, required: true, unique: true },
password: { type: String, required: true },
birthday: { type: Date, required: true },
celphoneNumber: String,
whatsapp: Boolean,
promo: Object,
status: String
});
UserSchema.pre<User>('save', async (next) => {
const user = this;
console.log(user);
if (user.password) {
const salt = await bcrypt.genSalt();
bcrypt.hash(user.password, salt, (err, hash) => {
if (err) return next(err);
user.password = hash;
next();
});
}
});
return UserSchema;
},
};
and my user Module comes below:
#Module({
imports: [
MongooseModule.forFeatureAsync([
UserSchemaProvider]),
HttpModule
],
controllers: [UsersController],
providers: [UsersService, Validator, ValidationPipe, IsEmailInUseConstraint, GoogleRecaptchaV3Constraint],
})
:Nest Platform Information:
platform-express version: 6.10.14
mongoose version: 6.3.1
common version: 6.10.14
core version: 6.10.14

Answer 1

Your pre hook handler shouldn't be an arrow function () => {}. mongoose handler will need to have the execution context to point to a current document being saved. When using arrow function, your execution context of the pre hook is no longer the document, hence, this inside of the handler isn't the document itself anymore.
export const UserSchemaProvider = {
name: 'User',
useFactory: (): mongoose.Model<User> => {
const UserSchema = new mongoose.Schema({
name: { type: String, required: true },
email: { type: String, required: true, unique: true },
password: { type: String, required: true },
birthday: { type: Date, required: true },
celphoneNumber: String,
whatsapp: Boolean,
promo: Object,
status: String
});
UserSchema.pre<User>('save', async function(next) { // <-- change to a function instead
const user = this;
console.log(user);
if (user.password) {
const salt = await bcrypt.genSalt();
bcrypt.hash(user.password, salt, (err, hash) => {
if (err) return next(err);
user.password = hash;
next();
});
}
});
return UserSchema;
},
};