TypeError: this.app.model is not a function

[damianlofi]

Hello, i am trying to create a REST API but when try to npm start i get this error:

app.repository() function is needed for RepositoryBooter. You can add it to your Application using RepositoryMixin from @loopback/repository.
app.dataSource() function is needed for DataSourceBooter. You can add it to your Application using RepositoryMixin from @loopback/repository.
Cannot start the application. TypeError: this.app.model is not a function
    at ModelBooter.load (/home/user/cloud/stable/new-backend/cloud-backend/node_modules/@loopback/boot/src/booters/model.booter.ts:58:32)
    at Bootstrapper.boot (/home/user/cloud/stable/new-backend/cloud-backend/node_modules/@loopback/boot/src/bootstrapper.ts:123:11)
    at CloudDosBackendApplication.boot (/home/damian/cloud/stable/new-backend/cloud-backend/node_modules/@loopback/boot/src/mixins/boot.mixin.ts:112:7)
    at main (/home/user/cloud/stable/new-backend/cloud-backend/src/index.ts:7:3)

I am using node v18.13.0

[nflaig]

Hey 👋, you need to add RepositoryMixin to your application class in application.ts file.

[damianlofi]

Hey, thanks for your answer. How do i add it? with just import {RepositoryMixin} from '@loopback/repository'; ? Also why do i have to do this, i cant find anything about it in documentation

[nflaig]

Usually the repository mixin should be there by default if you generate a LB4 app via the CLI.

You can add it like this

application.ts

class YourApplication extends RepositoryMixin(RestApplication) {}