Skip to main content

​
Overview

Data Service — is a layer that has two functions: database updates and domain functions. Database updates encapsulate the logic of updating and reading data in a database (also known as Repository Pattern in DDD). Domain functions use database updates to perform domain changes (e.x. changeUserEmail, updateCredentials, etc). For simplicity, we break the single responsibility pattern here. Data Service is usually named as entity.service (e.x. user.service).

​
Examples

import db from 'db';
import { DATABASE_DOCUMENTS } from 'app-constants';
import schema from './user.schema';

const service = db.createService(DATABASE_DOCUMENTS.USERS, {
  schemaValidator: (obj) => schema.parseAsync(obj),
});

async function createInvitationToUser(email: string, companyId: string) {
  // the logic
}

export default Object.assign(service, {
  createInvitationToUser,
});

​
Service API Quick Reference

db.createService returns a @paralect/node-mongo Service. Key methods:
  • find(filter, { page, perPage }, { sort }) → { results, pagesCount, count }
  • findOne(filter), insertOne(doc), updateOne(filter, updateFn), deleteSoft(filter)
  • exists(filter), distinct(field, filter), countDocuments(filter)
  • atomic.updateOne(filter, update) — raw MongoDB update (bypass schema validator)
  • createIndex(keys, options?) — call at module level in the service file

​
Soft Deletes

service.deleteSoft(filter) sets deletedOn timestamp instead of removing. All find/findOne queries auto-exclude deletedOn !== null.
The collection name must be registered in packages/app-constants/src/api.constants.ts → DATABASE_DOCUMENTS.