Error:Cannot read properties of undefined (reading 'prototype')

[shin4488]

Issue

when the models are added, the error Cannot read properties of undefined (reading 'prototype') happens.

Versions

• sequelize:6.19.0
• sequelize-typescript:2.1.3
• typescript:

the below is the content of package.json

{
  "dependencies": {
    "nuxt": "^2.15.8",
    "pg": "^8.7.3",
    "pg-hstore": "^2.3.4",
    "reflect-metadata": "^0.1.13",
    "sequelize": "^6.19.0",
    "sequelize-typescript": "^2.1.3",
    "vue": "^2.6.14",
    "webpack": "^4.46.0"
  },
  "devDependencies": {
    "@nuxt/types": "^2.15.8",
    "@nuxt/typescript-build": "^2.1.0",
    "@types/node": "^17.0.24",
    "@types/validator": "^13.7.2",
    "sequelize-cli": "^6.4.1"
  }
}

Issue type

• [x] bug report
• [ ] feature request

Actual behavior

the error happens when sequelize.addModels() is executed. I attached the error message just after the related code.

Expected behavior

the error is not happened and models can be added.

Steps to reproduce

create companyMaster.ts like the code. import companyMaster.ts in index.ts . execute index.ts .

I referenced the link about how to add models.

Related code

commons/sequelize/models/companyMaster.ts

import { Table, Column, Model } from 'sequelize-typescript';

@Table({
  schema: 'public',
  tableName: 'company_master',
  underscored: true,
  timestamps: true,
})
export class CompanyMaster extends Model {
  @Column
  companyNumber!: string;

  @Column
  companyName!: string;

  @Column
  homepageUrl!: string;
}

index.ts

import { Sequelize } from 'sequelize-typescript';
import { CompanyMaster } from './commons/sequelize/models/companyMaster';

const sequelize = new Sequelize(process.env.DB_CONNECTION_URI || '', {
  models: [__dirname + '/commons/sequelize/models'], // (edited) here also the error happens.
});
sequelize.addModels([CompanyMaster]); // the error happens here

the error message for the line sequelize.addModels([CompanyMaster]);

Cannot read properties of undefined (reading 'prototype')

  at node_modules/sequelize-typescript/dist/sequelize/sequelize/sequelize.js:62:71
  at Array.map (<anonymous>)
  at Sequelize.defineModels (node_modules/sequelize-typescript/dist/sequelize/sequelize/sequelize.js:61:23)
  at Sequelize.addModels (node_modules/sequelize-typescript/dist/sequelize/sequelize/sequelize.js:37:36)
  at server/index.ts:30:15
  at runMicrotasks (<anonymous>)
  at processTicksAndRejections (node:internal/process/task_queues:96:5)

(edited) the error message for the line models: [__dirname + '/commons/sequelize/models'],

Cannot find module 'commons/sequelize/models/companyMaster'

Require stack:
  - node_modules/sequelize-typescript/dist/sequelize/sequelize/sequelize-service.js
  - node_modules/sequelize-typescript/dist/sequelize/sequelize/sequelize.js
  - node_modules/sequelize-typescript/dist/index.js
  - server/index.ts

  at Function.Module._resolveFilename (node:internal/modules/cjs/loader:933:15)
  at Function.Module._resolveFilename (node_modules/module-alias/index.js:49:29)
  at Function.Module._load (node:internal/modules/cjs/loader:778:27)
  at Module.require (node:internal/modules/cjs/loader:1005:19)
  at require (node:internal/modules/cjs/helpers:102:18)
  at node_modules/sequelize-typescript/dist/sequelize/sequelize/sequelize-service.js:45:32
  at Array.map (<anonymous>)
  at node_modules/sequelize-typescript/dist/sequelize/sequelize/sequelize-service.js:43:18
  at Array.reduce (<anonymous>)
  at getModels (node_modules/sequelize-typescript/dist/sequelize/sequelize/sequelize-service.js:35:20)
  at Sequelize.addModels (node_modules/sequelize-typescript/dist/sequelize/sequelize/sequelize.js:36:58)
  at new Sequelize (node_modules/sequelize-typescript/dist/sequelize/sequelize/sequelize.js:20:22)
  at server/index.ts:24:23
  at Layer.handle [as handle_request] (node_modules/express/lib/router/layer.js:95:5)
  at next (node_modules/express/lib/router/route.js:137:13)
  at Route.dispatch (node_modules/express/lib/router/route.js:112:3)

[p4nthera115]

Did you ever figure this out? I have the exact same issue :(

[Jace-Tech]

Anyone got solution on this?

[gutierrezj2]

i have same error, it worked fine when i had the models locally to the project but i get this error when trying to load them from a library

[tefkah]

fwiw this is probably a problem bc you are using nuxt, which uses vite, which uses esbuild, which does not support typescripts emitDecoratorMetadata, which sequelize-typescript relies on.