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Using Typescript interface as a variable

I am working on a Node Js (TypeScript) architecture and for some reason, I want to bind my interface to a specific object. I am making a general class that is extended by other subclasses and it will have a very general code. So my code looks like
interface User {
name: string;
}
interface Profile {
title: string;
}
class Parent {
name: string;
interface: Interface; // Help required here, getting error can't use type as a variable
constructor( name, interface ) {
// Load schema and store here
this.name = name
this.interface = interface
}
// Though this is not correct I hope you get the idea of what I am trying to do
get (): this.interface {
// fetch the data and return
return data
}
set (data: this.interface): void {
// adding new data
}
}
class UserSchema extends Parent {
// Class with custom functions for UserSchema
}
class ProfileSchema extends Parent {
// Class with custom functions for ProfileSchema
}
// Config file that saves the configs for different modules
const moduleConfig = [
{
name: "User Module",
class: UserSchema,
interface: User
},
{
name: "Profile Module",
class: ProfileSchema,
interface: Profile
},
]
const allModules = {}
// Loading the modules
moduleConfig.map(config => {
allModules[config.name] = new config.class(
config.name,
config.interface
)
})
export allModules;
I need suggestions on how should I bind my interfaces with their respective configs. Till now I have had no luck with that.
PS: All this code is separated into their respective files.

This is the use case for generics. You can even see them as "variable for types".
Instead of having an interface property in your Parent class, the latter would have a generic type:
class Parent<T> { // T is the generic type
name: string;
// interface: Interface; // generic is already provided at class level
constructor( name ) {
// Load schema and store here
this.name = name
}
get (): T {
// fetch the data and return
return data
}
set (data: T): void {
// adding new data
}
}
// Here you specify the concrete generic type
class UserSchema extends Parent<User> {
// Class with custom functions for UserSchema
}
class ProfileSchema extends Parent<Profile> {
// Class with custom functions for ProfileSchema
}

Using Mongoose and Typescript, what type should be used for a ref field of an interface?

I am using mongoose and Typescript, and I am wanting to know what type, or types, I should be using for a reference field, when creating an interface? Consider the following two related interfaces:
interface ICat {
name: string,
colour: string,
}
interface ICatDB extends ICat, Document {};
interface IMouse {
name: string,
colour: string,
chasedBy: /* ... */
}
interface IMouseDB extends IMouse, Document {};
And the schemas and models that use them:
let cat = new Schema({
name: String,
colour: String,
});
mongoose.model<ICatDB>('Cat', cat);
let mouse = new Schema({
name: String,
colour: String,
chasedBy: { type: Schema.Types.ObjectId, ref: 'Cat' }
});
mongoose.model<IMouseDB>('Mouse', mouse);
For the chasedBy field we need to consider that it can take values in three forms:
String or ObjectId, when passed to a create() method
ObjectId when returned from Mongoose
Instance of ICat when returned from Mongoose, using populate()
Is there a way that we can specify the types the interface can support, without having to resort to using any?
BTW we separated IMouse and IMouseDB, since Typescript wanted all the fields for Document filled out every time we created a new IMouse object, so this was a work around.

At least for version 5.x you could use this:
https://mongoosejs.com/docs/5.x/docs/typescript/populate.html
import { PopulatedDoc } from 'mongoose';
import ICat from './ICat';
interface IMouse {
name: string,
colour: string,
chasedBy: PopulatedDoc<ICat>
}
The docs in 6.x shows different approach:
https://mongoosejs.com/docs/typescript/populate.html
like this:
MouseModel.findOne({}).populate<{chasedBy: ICat}>('chasedBy');

Lacking any alternative answer, I went with:
import { ObjectID } from 'mongodb';
import ICat from './ICat';
interface IMouse {
name: string,
colour: string,
chasedBy: string | ObjectID | ICat
}
This describes the type variants for the 'chasedBy' property. As to whether this is the recommended approach, I can't say.

Mongoose 6.x
Mongoose offers type declarations in mongoose.Types
interface Mouse { // important: don't use I in front of the name and don't extend Document
chasedBy: mongoose.Types.ObjectId
}

How to define custom query helper in mongoose model with typescript?

I want to define custom query helper using query helper api .
Here the example:
// models/article.ts
import { Document, Schema, Model, model } from 'mongoose';
interface IArticle extends Document {
name: string;
}
interface IArticleModel extends Model<IArticle> {
someStaticMethod(): Promise<any>;
}
const ArticleSchema = new Schema( { name: String } )
ArticleSchema.query.byName = function(name) {
return this.find({ name })
}
export default model<IArticle, IArticleModel>('Article', ArticleSchema);
// routes/article.ts
import ArticleModel from '../models/article.ts'
router.get('/articles, (req, res) => {
ArticleModel.find().byName('example')
})
Typescript complains about byName method when I chain it with defaults.
I can put it in IArticleModel interface but in that case I could only call it from model.
Where should I put the definition of this method to use it in chainable way?

I've drafted a new version of #types/mongoose that supports query helpers. See this answer for ways to install a modified #types package. With my version, you should be able to write the following in models/article.ts:
import { Document, Schema, Model, model, DocumentQuery } from 'mongoose';
interface IArticle extends Document {
name: string;
}
interface IArticleModel extends Model<IArticle, typeof articleQueryHelpers> {
someStaticMethod(): Promise<any>;
}
const ArticleSchema = new Schema( { name: String } )
let articleQueryHelpers = {
byName(this: DocumentQuery<any, IArticle>, name: string) {
return this.find({ name });
}
};
ArticleSchema.query = articleQueryHelpers;
export default model<IArticle, IArticleModel>('Article', ArticleSchema);
and then routes/article.ts will work. If this works for you, then I will submit a pull request to the original package on DefinitelyTyped.

Let classes inherit from type aliases

I try to create a user class and want to be able to inherit from a type alias:
type PlainUser = { email: string }
class User extends PlainUser {
constructor (initialValues: PlainUser) {
this.email = initialValues.email
}
update () { ... }
}
This doesn't work of course, but I would like to have the following semantics without having to duplicate email (and all the other fields that I don't show to keep it brief):
type PlainUser = { email: string }
class User {
email: string
constructor (initialValues: PlainUser) {
this.email = initialValues.email
}
update () { ... }
}
Is this possible with flow?

Not that I know of, but you can at least use implements to enforce that the User class implements the PlainUser interface (yes, you have to change it to be an interface).
interface PlainUser {
email: string;
}
class Foo implements PlainUser {
}
(tryflow)
The code above yields the following error with Flow v0.41, since Foo does not specify an email property:
7: class Foo implements PlainUser {
^ property `email` of PlainUser. Property not found in
7: class Foo implements PlainUser {
^ Foo
Of course, this isn't exactly what you've asked for. But at least you are getting automatic checking that User implements PlainUser, rather than nothing at all.

You can only extend from classes, and your type alias is an interface, so you have to use implement here. TypeScript Salsa allows doing the following since this suggestion was implemented:
type PlainUser = { email: string };
class User implements PlainUser {
constructor (initialValues: PlainUser) {
this.email = initialValues.email;
}
}
If you do not use salsa, you have to explicitly declare the inherited properties:
type PlainUser = { email: string };
class User implements PlainUser {
public email: string;
constructor (initialValues: PlainUser) {
this.email = initialValues.email;
}
}
Playground

I'll admit this was a head scratcher initially, but something like what you want to do is very possible. It does require rethinking the approach a bit.
First, you need to start with the class instead of the object literal. Intuitively this makes sense, as that's also the way javascript works.
class User {
email: string;
}
Next you want to use flow's $Shape transformation. This will cast your type to the enumerable properties of the class.
type PlainUser = $Shape<User>;
const Bob: PlainUser = { email: "bob#bob.com" }
or
const BobProperties: PlainUser = { ...new PlainUserClass("bob#bob.com") }
Finally, extend the User class as normal.
class AdminUser extends User {
admin: true;
}
example

Mongoose the Typescript way...?

Trying to implement a Mongoose model in Typescript. Scouring the Google has revealed only a hybrid approach (combining JS and TS). How would one go about implementing the User class, on my rather naive approach, without the JS?
Want to be able to IUserModel without the baggage.
import {IUser} from './user.ts';
import {Document, Schema, Model} from 'mongoose';
// mixing in a couple of interfaces
interface IUserDocument extends IUser, Document {}
// mongoose, why oh why '[String]'
// TODO: investigate out why mongoose needs its own data types
let userSchema: Schema = new Schema({
userName : String,
password : String,
firstName : String,
lastName : String,
email : String,
activated : Boolean,
roles : [String]
});
// interface we want to code to?
export interface IUserModel extends Model<IUserDocument> {/* any custom methods here */}
// stumped here
export class User {
constructor() {}
}

Here's how I do it:
export interface IUser extends mongoose.Document {
name: string;
somethingElse?: number;
};
export const UserSchema = new mongoose.Schema({
name: {type:String, required: true},
somethingElse: Number,
});
const User = mongoose.model<IUser>('User', UserSchema);
export default User;

Another alternative if you want to detach your type definitions and the database implementation.
import {IUser} from './user.ts';
import * as mongoose from 'mongoose';
type UserType = IUser & mongoose.Document;
const User = mongoose.model<UserType>('User', new mongoose.Schema({
userName : String,
password : String,
/* etc */
}));
Inspiration from here: https://github.com/Appsilon/styleguide/wiki/mongoose-typescript-models

Most answers here repeat the fields in the TypeScript class/interface, and in the mongoose schema. Not having a single source of truth represents a maintenance risk, as the project becomes more complex and more developers work on it: fields are more likely to get out of sync. This is particularly bad when the class is in a different file vs. the mongoose schema.
To keep fields in sync, it makes sense to define them once. There are a few libraries that do this:
typeodm.io - full test coverage, good examples, no traction yet
mongoose-decorators-ts - best English, no traction yet
typegoose - most popular, documentation needs improvement
ts-mongoose - doesn't use decorators, second most popular, not actively maintained
mongoose-schema-decorators - no traction yet
mongoose-typescript - fork of typegoose
I haven't yet been fully convinced by any of them but typegoose seems actively maintained, and the developer accepted my PRs.
To think one step ahead: when you add a GraphQL schema into the mix, another layer of model duplication appears. One way to overcome this problem might be to generate TypeScript and mongoose code from the GraphQL schema.

Sorry for necroposting but this can be still interesting for someone.
I think Typegoose provides more modern and elegant way to define models
Here is an example from the docs:
import { prop, Typegoose, ModelType, InstanceType } from 'typegoose';
import * as mongoose from 'mongoose';
mongoose.connect('mongodb://localhost:27017/test');
class User extends Typegoose {
#prop()
name?: string;
}
const UserModel = new User().getModelForClass(User);
// UserModel is a regular Mongoose Model with correct types
(async () => {
const u = new UserModel({ name: 'JohnDoe' });
await u.save();
const user = await UserModel.findOne();
// prints { _id: 59218f686409d670a97e53e0, name: 'JohnDoe', __v: 0 }
console.log(user);
})();
For an existing connection scenario, you can use as the following (which may be more likely in the real situations and uncovered in the docs):
import { prop, Typegoose, ModelType, InstanceType } from 'typegoose';
import * as mongoose from 'mongoose';
const conn = mongoose.createConnection('mongodb://localhost:27017/test');
class User extends Typegoose {
#prop()
name?: string;
}
// Notice that the collection name will be 'users':
const UserModel = new User().getModelForClass(User, {existingConnection: conn});
// UserModel is a regular Mongoose Model with correct types
(async () => {
const u = new UserModel({ name: 'JohnDoe' });
await u.save();
const user = await UserModel.findOne();
// prints { _id: 59218f686409d670a97e53e0, name: 'JohnDoe', __v: 0 }
console.log(user);
})();

Try ts-mongoose. It uses conditional types to do the mapping.
import { createSchema, Type, typedModel } from 'ts-mongoose';
const UserSchema = createSchema({
username: Type.string(),
email: Type.string(),
});
const User = typedModel('User', UserSchema);

Here's a strong typed way to match a plain model with a mongoose schema. The compiler will ensure the definitions passed to mongoose.Schema matches the interface. Once you have the schema, you can use
common.ts
export type IsRequired<T> =
undefined extends T
? false
: true;
export type FieldType<T> =
T extends number ? typeof Number :
T extends string ? typeof String :
Object;
export type Field<T> = {
type: FieldType<T>,
required: IsRequired<T>,
enum?: Array<T>
};
export type ModelDefinition<M> = {
[P in keyof M]-?:
M[P] extends Array<infer U> ? Array<Field<U>> :
Field<M[P]>
};
user.ts
import * as mongoose from 'mongoose';
import { ModelDefinition } from "./common";
interface User {
userName : string,
password : string,
firstName : string,
lastName : string,
email : string,
activated : boolean,
roles : Array<string>
}
// The typings above expect the more verbose type definitions,
// but this has the benefit of being able to match required
// and optional fields with the corresponding definition.
// TBD: There may be a way to support both types.
const definition: ModelDefinition<User> = {
userName : { type: String, required: true },
password : { type: String, required: true },
firstName : { type: String, required: true },
lastName : { type: String, required: true },
email : { type: String, required: true },
activated : { type: Boolean, required: true },
roles : [ { type: String, required: true } ]
};
const schema = new mongoose.Schema(
definition
);
Once you have your schema, you can use methods mentioned in other answers such as
const userModel = mongoose.model<User & mongoose.Document>('User', schema);

Just add another way (#types/mongoose must be installed with npm install --save-dev #types/mongoose)
import { IUser } from './user.ts';
import * as mongoose from 'mongoose';
interface IUserModel extends IUser, mongoose.Document {}
const User = mongoose.model<IUserModel>('User', new mongoose.Schema({
userName: String,
password: String,
// ...
}));
And the difference between interface and type, please read this answer
This way has a advantage, you can add Mongoose static method typings:
interface IUserModel extends IUser, mongoose.Document {
generateJwt: () => string
}

Here's how guys at Microsoft do it. here
import mongoose from "mongoose";
export type UserDocument = mongoose.Document & {
email: string;
password: string;
passwordResetToken: string;
passwordResetExpires: Date;
...
};
const userSchema = new mongoose.Schema({
email: { type: String, unique: true },
password: String,
passwordResetToken: String,
passwordResetExpires: Date,
...
}, { timestamps: true });
export const User = mongoose.model<UserDocument>("User", userSchema);
I recommend to check this excellent starter project out when you add TypeScript to your Node project.
https://github.com/microsoft/TypeScript-Node-Starter

If you want to ensure that your schema satisfies the model type and vice versa , this solution offers better typing than what #bingles suggested:
The common type file:
ToSchema.ts (Don't panic! Just copy and paste it)
import { Document, Schema, SchemaType, SchemaTypeOpts } from 'mongoose';
type NonOptionalKeys<T> = { [k in keyof T]-?: undefined extends T[k] ? never : k }[keyof T];
type OptionalKeys<T> = Exclude<keyof T, NonOptionalKeys<T>>;
type NoDocument<T> = Exclude<T, keyof Document>;
type ForceNotRequired = Omit<SchemaTypeOpts<any>, 'required'> & { required?: false };
type ForceRequired = Omit<SchemaTypeOpts<any>, 'required'> & { required: SchemaTypeOpts<any>['required'] };
export type ToSchema<T> = Record<NoDocument<NonOptionalKeys<T>>, ForceRequired | Schema | SchemaType> &
Record<NoDocument<OptionalKeys<T>>, ForceNotRequired | Schema | SchemaType>;
and an example model:
import { Document, model, Schema } from 'mongoose';
import { ToSchema } from './ToSchema';
export interface IUser extends Document {
name?: string;
surname?: string;
email: string;
birthDate?: Date;
lastLogin?: Date;
}
const userSchemaDefinition: ToSchema<IUser> = {
surname: String,
lastLogin: Date,
role: String, // Error, 'role' does not exist
name: { type: String, required: true, unique: true }, // Error, name is optional! remove 'required'
email: String, // Error, property 'required' is missing
// email: {type: String, required: true}, // correct 👍
// Error, 'birthDate' is not defined
};
const userSchema = new Schema(userSchemaDefinition);
export const User = model<IUser>('User', userSchema);

I am a fans of Plumier, it has mongoose helper, but it can be used standalone without Plumier itself. Unlike Typegoose its took different path by using Plumier's dedicated reflection library, that make it possible to use cools stuff.
Features
Pure POJO (domain doesn't need to inherit from any class, nor using any special data type), Model created automatically inferred as T & Document thus its possible to access document related properties.
Supported TypeScript parameter properties, it's good when you have strict:true tsconfig configuration. And with parameter properties doesn't require decorator on all properties.
Supported field properties like Typegoose
Configuration is the same as mongoose so you will get easily familiar with it.
Supported inheritance that's make the programming more natural.
Model analysis, showing model names and its appropriate collection name, configuration applied etc.
Usage
import model, {collection} from "#plumier/mongoose"
#collection({ timestamps: true, toJson: { virtuals: true } })
class Domain {
constructor(
public createdAt?: Date,
public updatedAt?: Date,
#collection.property({ default: false })
public deleted?: boolean
) { }
}
#collection()
class User extends Domain {
constructor(
#collection.property({ unique: true })
public email: string,
public password: string,
public firstName: string,
public lastName: string,
public dateOfBirth: string,
public gender: string
) { super() }
}
// create mongoose model (can be called multiple time)
const UserModel = model(User)
const user = await UserModel.findById()

2023 Update
The new recommended way of typing documents is using a single interface. To type documents in your application, you should use HydratedDocument:
import { HydratedDocument, model, Schema } from "mongoose";
interface Animal {
name: string;
}
const animalSchema = new Schema<Animal>({
name: { type: String, required: true },
});
const AnimalModel = model<Animal>("Animal", animalSchema);
const animal: HydratedDocument<Animal> = AnimalModel.findOne( // ...
Mongoose advises against extending document.
https://mongoosejs.com/docs/typescript.html

Here is the example from Mongoose documentation, Creating from ES6 Classes Using loadClass(), converted to TypeScript:
import { Document, Schema, Model, model } from 'mongoose';
import * as assert from 'assert';
const schema = new Schema<IPerson>({ firstName: String, lastName: String });
export interface IPerson extends Document {
firstName: string;
lastName: string;
fullName: string;
}
class PersonClass extends Model {
firstName!: string;
lastName!: string;
// `fullName` becomes a virtual
get fullName() {
return `${this.firstName} ${this.lastName}`;
}
set fullName(v) {
const firstSpace = v.indexOf(' ');
this.firstName = v.split(' ')[0];
this.lastName = firstSpace === -1 ? '' : v.substr(firstSpace + 1);
}
// `getFullName()` becomes a document method
getFullName() {
return `${this.firstName} ${this.lastName}`;
}
// `findByFullName()` becomes a static
static findByFullName(name: string) {
const firstSpace = name.indexOf(' ');
const firstName = name.split(' ')[0];
const lastName = firstSpace === -1 ? '' : name.substr(firstSpace + 1);
return this.findOne({ firstName, lastName });
}
}
schema.loadClass(PersonClass);
const Person = model<IPerson>('Person', schema);
(async () => {
let doc = await Person.create({ firstName: 'Jon', lastName: 'Snow' });
assert.equal(doc.fullName, 'Jon Snow');
doc.fullName = 'Jon Stark';
assert.equal(doc.firstName, 'Jon');
assert.equal(doc.lastName, 'Stark');
doc = (<any>Person).findByFullName('Jon Snow');
assert.equal(doc.fullName, 'Jon Snow');
})();
For the static findByFullName method, I couldn't figure how get the type information Person, so I had to cast <any>Person when I want to call it. If you know how to fix that please add a comment.

With this vscode intellisense works on both
User Type User.findOne
user instance u1._id
The Code:
// imports
import { ObjectID } from 'mongodb'
import { Document, model, Schema, SchemaDefinition } from 'mongoose'
import { authSchema, IAuthSchema } from './userAuth'
// the model
export interface IUser {
_id: ObjectID, // !WARNING: No default value in Schema
auth: IAuthSchema
}
// IUser will act like it is a Schema, it is more common to use this
// For example you can use this type at passport.serialize
export type IUserSchema = IUser & SchemaDefinition
// IUser will act like it is a Document
export type IUserDocument = IUser & Document
export const userSchema = new Schema<IUserSchema>({
auth: {
required: true,
type: authSchema,
}
})
export default model<IUserDocument>('user', userSchema)

I find the following approach the easiest and most efficient since it validates the keys in the schema with the extra interface you define, helping you keep everything in sync.
You also get the amazing typescript autocomplete suggestions when you are adding/changing schema validator properties like maxlength, lowercase, etc on the schema.
Win win!
import { Document, model, Schema, SchemaDefinitionProperty } from "mongoose";
type TDocument<Fields> = Fields & Document;
type TSchema<Fields> = Record<keyof Fields, SchemaDefinitionProperty>;
type UserFields = {
email: string;
firstName?: string;
roles?: string[];
};
const userSchema: TSchema<UserFields> = {
email: { type: Schema.Types.String, required: true, index: true },
firstName: { type: Schema.Types.String, maxlength: 30, trim: true },
roles: [
{ type: Schema.Types.String, maxlength: 20, lowercase: true },
],
};
export const User = model<TDocument<UserFields>>(
"User",
new Schema(userSchema, { timestamps: true })
);
Best part! you could reuse TDocument and TSchema types for all your models.

For anyone looking for a solution for existing Mongoose projects:
We recently built mongoose-tsgen to address this issue (would love some feedback!). Existing solutions like typegoose required rewriting our entire schemas and introduced various incompatibilities. mongoose-tsgen is a simple CLI tool which generates an index.d.ts file containing Typescript interfaces for all your Mongoose schemas; it requires little to no configuration and integrates very smoothly with any Typescript project.

Official documents discourage TS interface to extend Document.
This approach works, but we recommend your document interface not extend Document. Using extends Document makes it difficult for Mongoose to infer which properties are present on query filters, lean documents, and other cases.
TS Interface
export interface IPerson {
firstName: string;
lastName: string;
fullName: string;
}
Schema
const personSchema = new Schema<IPerson>({
//You get intellisense of properties so less error prone
firstName:{type:String},
lastName:{type:String}
})
personSchema.virtual('fullName').get(function(this:IPerson) {
return this.firstName + " " this.lastName
});
export const User = model<IPerson>('person',personSchema)

Mongoose introduced officially supported TypeScript bindings in v5.11.0.
https://mongoosejs.com/docs/typescript.html describes Mongoose's recommended approach to working with Mongoose in TypeScript.

Here is an example based off the README for the #types/mongoose package.
Besides the elements already included above it shows how to include regular and static methods:
import { Document, model, Model, Schema } from "mongoose";
interface IUserDocument extends Document {
name: string;
method1: () => string;
}
interface IUserModel extends Model<IUserDocument> {
static1: () => string;
}
var UserSchema = new Schema<IUserDocument & IUserModel>({
name: String
});
UserSchema.methods.method1 = function() {
return this.name;
};
UserSchema.statics.static1 = function() {
return "";
};
var UserModel: IUserModel = model<IUserDocument, IUserModel>(
"User",
UserSchema
);
UserModel.static1(); // static methods are available
var user = new UserModel({ name: "Success" });
user.method1();
In general, this README appears to be a fantastic resource for approaching types with mongoose.

The latest mongoose package has come with typescript support. You don't need to use #types/mongoose anymore. See my example here.
https://jasonching2005.medium.com/complete-guide-for-using-typescript-in-mongoose-with-lean-function-e55adf1189dc

Well, I found the following link really really helpful where the author has described each and every step in details without using any library.
Typescript With MongoDB and Node/Express
This has really really helped me and hoping will be very helpful for those searching for a solution without installing any extra plugin.
However, if you like you can give a try to TypeORM and TypeGoose
But I prefer to go without installing any library :-).

v6.9 update
You don't need to create a type or an interface no more. You only need a schema to generate the corresponding types:
import { model, Schema, HydratedDocumentFromSchema, InferSchemaType } from "mongoose";
const UserSchema = new Schema({
name: { type: String, required: true },
somethingElse: Number
});
// Already typed
export const UserModel = model('User', UserSchema);
// Type of an hydrated document (with all the getters, etc...)
export type THydratedUserModel = HydratedDocumentFromSchema<typeof UserSchema>;
// Only the fields defined in the shema
export type TUserModel = InferSchemaType<typeof UserSchema>;
⚠️ As of writing this, these type helpers (HydratedDocumentFromSchema and InferSchemaType) are undocumented.

As per mongoose docs
Alternatively, your document interface can extend Mongoose's Document
class.
We strongly recommend against using this approach, its support will be
dropped in the next major version as it causes major performance
issues.
Instead you can use HydratedDocument
export interface User {
name: string;
email: string;
password: string;
phone: string;
address: string[];
orders: ObjectId[];
}
export type UserDoc = HydratedDocument<User>

Not sure this is what you are looking for
but there's a package called Typegoose

TypeORM is a better and modern solution. It supports both JavaScript and TypeScript.
TypeORM is an ORM that can run in NodeJS, Browser, Cordova, PhoneGap, Ionic, React Native, NativeScript, Expo, and Electron platforms and can be used with TypeScript and JavaScript (ES5, ES6, ES7, ES8).
It has lots of features.
Its goal is to always support the latest JavaScript features and provide additional features that help you to develop any kind of application that uses databases - from small applications with a few tables to large scale enterprise applications with multiple databases.
It supports most databases like mysql, mariadb, postgres, cockroachdb, sqlite, mssql, oracle, etc. and mongodb as well.
TypeORM supports both Active Record and Data Mapper patterns, unlike
all other JavaScript ORMs currently in existence, which means you can
write high quality, loosely coupled, scalable, maintainable
applications the most productive way.
So no need to learn different ORM or frameworks for different databases.