zeichen-backend/src/utilities/ORM.ts

import { Sequelize, Dialect, } from 'sequelize'
import * as ColumnTypes from './ColumnTypes'

export enum DatabaseKind {
  MSSQL = 'mssql',
  SQLITE = 'sqlite',
  MYSQL = 'mysql',
  MARIADB = 'mariadb',
  POSTGRESQL = 'postgres',
}

type RepositoryParams = {
  url: string,
  kind: DatabaseKind,
}

export default class ORM {
  private readonly instance: Sequelize

  constructor(params: RepositoryParams) {
    const { kind, url, } = params
    switch (kind as DatabaseKind) {
      case DatabaseKind.SQLITE:
        this.instance = new Sequelize({
          dialect: kind as string as Dialect,
          storage: url,
        })
        return
      case DatabaseKind.POSTGRESQL:
      case DatabaseKind.MARIADB:
      case DatabaseKind.MSSQL:
      case DatabaseKind.MYSQL:
        this.instance = new Sequelize({
          dialect: kind as string as Dialect,
          host: url,
        })
        return
      // TODO add nosql dbs
      default:
        break
    }
    throw new Error(`Database kind "${kind as string}" not yet supported.`)
  }

  getRepository(model: ColumnTypes.Model) {
    if (this.instance instanceof Sequelize) {
      return this.instance.define(model.modelName, model.attributes, model.options)
    }
    throw new Error('Interface not yet initialized.')
  }
}