How to set up Typegoose

If you want to programm an API under the following conditions, you can use the provided minimal example below:

Conditions: NodeJSTypescriptMongoDB (locally)

Example:

If you are working with typescript, a project structure, similar to this is recommended:

├── dist|   ├── (your compiled JS)├── src|   ├── models|   |   ├── user.model.ts|   ├── user-repository.ts|   ├── app.ts|   ├── index.ts├── test|   ├── (your tests)

Furthermore, it's required to install the following packages

npm install --save typescript mongoose express @types/express @types/mongoose typegoose

index.ts:

This file, I just have for bootstraping purposes

import app from './app';const port = 3000;app.listen(port, (err) => {    if (err) {        return console.log(err);    }    return console.log('Server up and running on ' + port);});

app.ts:

Here, the actual logic is going on

import { UserRepository } from './user-repository';import * as express from 'express';export class App {    public app;    constructor() {        this.app = express();        this.config();        this.mountRoutes();    }    private mountRoutes() {        // Definition of the possible API routes        this.app.route('/users')            .get((req, res) => {                var repo = new UserRepository();                // we catch the result with the typical "then"                repo.getUsers().then((x) => {                    // .json(x) instead of .send(x) should also be okay                    res.status(200).send(x);                });            });        //               here with parameter        //                      |        //                      v        this.app.route('/users/:id')            .get((req, res) => {                var repo = new UserRepository();                repo.getUser(req.params.id).then((x) => {                    res.status(200).send(x);            });        });    }}export default new App().app;

user-repository.ts

import * as mongoose from 'mongoose';import { User, UserModel } from './models/user.model';export class UserRepository {    constructor() {        //                protocol  host      port  database        //                   |       |         |        |        //                   v       v         v        v        mongoose.connect('mongodb://localhost:27017/mongotest');        // this only works, if your mongodb has no auth configured        // if you need authentication, use the following:        // mongoose.connect(MONGO_URL, {        //     auth: {        //         user: MONGO_DB_USER,        //         password: MONGO_DB_PASSWORD        //     },        // })    }    async getUser(id: number): Promise<User> {        //                  json query object as usual        //                               |        //                               v        return UserModel.findOne({"userId": id});    }    async getUsers(): Promise<User[]> {        return UserModel.find({});    }}

user.model.ts

import * as mongoose from 'mongoose';import { prop, Typegoose } from 'typegoose';export class User extends Typegoose{    // properties    // |    // v    @prop()    userId: number;    @prop()    firstname?: string;    @prop()    lastname: string;    @prop()    email: string;}export const UserModel = new User().getModelForClass(User, {    existingMongoose: mongoose,    //  had many problems without that definition of the collection name    //  so better define it    //                        |    //                        v    schemaOptions: {collection: 'users'}})

As obvious, I had a mongodb running locally, having a database called mongotest and inside that a collection called users.