How to setup NextJS with Mongoose and TypeScript

To get started with Mongoose and TypeScript, you need to:

1. Create an interface representing a document in MongoDB.
2. Create a Schema corresponding to the document interface.
3. Create a Model.
4. Export the model

1import { Model, Types, Schema, model, models } from "mongoose";
2
3export interface UserProps {
4  _id: Types.ObjectId;
5  firstName: string;
6  lastName: string;
7  email: string;
8  password: string;
9  avatar: Buffer;
10  createdAt: Date;
11  updatedAt: Date;
12}
13
14const userSchema = new Schema<UserProps>(
15  {
16    firstName: {
17      type: String,
18      required: [true, "First name is required"],
19    },
20    lastName: {
21      type: String,
22      required: [true, "Last name is required"],
23    },
24    email: {
25      type: String,
26      required: [true, "Email is required"],
27      unique: true,
28      lowercase: true,
29      },
30   
31    password: {
32      type: String,
33      required: [true, "Password is required"],
34    },
35
36    avatar: {
37      type: Buffer,
38    },
39  },
40  { timestamps: true }
41);
42
43
44const User =
45  (models.User as Model<UserProps>) ||
46  model<UserProps>("User", userSchema);
47
48export default User;
49

Creating refs using ObjectIds

When you want to reference a mongoose model inside another model, you should use Types.ObjectId in the TypeScript document interface and ObjectId or Schema.Types.ObjectId inside your schema definition according to the mongoose documentation.

1import { Schema, Types } from 'mongoose';
2
3 // Use **Types.ObjectId** in document interface.
4interface PostProps {
5...
6authorID:Types.ObjectId
7}
8
9// And **Schema.Types.ObjectId** in the schema definition.
10const postSchema = new Schema<PostProps>({
11...
12authorID:{
13type : Schema.Types.ObjectId,
14ref:"User"
15})