How do you add schema middleware (hooks) and instance methods in NestJS Mongoose?

Q: How do you add schema middleware (hooks) and instance methods in NestJS Mongoose?

@Schema({ timestamps: true }) export class User { @Prop() email: string; @Prop({ select: false }) password: string; @Prop() firstName: string; @Prop() lastName: string; } export const UserSchema = SchemaFactory.createForClass(User); // Pre-save hook — hash password before persisting UserSchema.pre('save', async function(next) { if (!this.isModified('password')) return next(); this.password = await bcrypt.hash(this.password, 12); next(); }); // Instance method — compare plain password against hash UserSchema.methods.comparePassword = async function( candidate: string, ): Promise { return bcrypt.compare(candidate, this.password); }; // Static method — reusable query UserSchema.statics.findActive = function() { return this.find({ isActive: true }); }; // Virtual — computed, not stored in DB UserSchema.virtual('fullName').get(function() { return `${this.firstName} ${this.lastName}`; }); // TypeScript interface for typed instance methods export interface UserDocument extends User, Document { comparePassword(candidate: string): Promise ; } Apply hooks and methods to the schema object before registering it in MongooseModule.forFeature(). Use regular functions (not arrow functions) in hooks and methods — arrow functions do not bind this. this.isModified('field') in pre-save hooks avoids rehashing an already-hashed password. Extend the document interface to get TypeScript typing for instance methods. Virtuals are not included in JSON output by default — set { toJSON: { virtuals: true } } on the schema.

Difficulty: 5/10

Schema Middleware, Instance Methods, NestJS Mongoose Integration

Add pre/post hooks and instance methods directly on the schema object returned by SchemaFactory.createForClass() before it is registered in the module. Pre-save hooks are the standard location for password hashing. Extend the document type with a TypeScript interface to get typed access to instance methods.

Pre-save hook, instance method, and virtual

Mongoose hooks and methods rules:

1
Apply hooks and methods to the schema object before registering it in MongooseModule.forFeature().
2

How do you add schema middleware (hooks) and instance methods in NestJS Mongoose?

Difficulty: 5/10

Schema Middleware, Instance Methods, NestJS Mongoose Integration

Add pre/post hooks and instance methods directly on the schema object returned by SchemaFactory.createForClass() before it is registered in the module. Pre-save hooks are the standard location for password hashing. Extend the document type with a TypeScript interface to get typed access to instance methods.

Pre-save hook, instance method, and virtual

Mongoose hooks and methods rules:

1
Apply hooks and methods to the schema object before registering it in MongooseModule.forFeature().
2

How do you add schema middleware (hooks) and instance methods in NestJS Mongoose?

How do you add schema middleware (hooks) and instance methods in NestJS Mongoose?

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