# Services

Services are a set of reusable functions. They are particularly useful to respect the "don’t repeat yourself" (DRY) programming concept and to simplify controllers logic.

# Implementation

Services can be generated or added manually. Strapi provides a createCoreService factory function that automatically generates core services and allows building custom ones or extend or replace the generated services.

# Adding a new service

A new service can be implemented:

To manually create a service, export a factory function that returns the service implementation (i.e. an object with methods). This factory function receives the strapi instance:

// path: ./src/api/restaurant/services/restaurant.js

const { createCoreService } = require('@strapi/strapi').factories;

module.exports = createCoreService('api::restaurant.restaurant', ({ strapi }) =>  ({
  // Method 1: Creating an entirely custom service
  async exampleService(...args) {
    let response = { okay: true }

    if (response.okay === false) {
      return { response, error: true }

    return response

  // Method 2: Wrapping a core service (leaves core logic in place)
  async find(...args) {  
    // Calling the default core controller
    const { results, pagination } = await super.find(...args);

    // some custom logic
    results.forEach(result => {
      result.counter = 1;

    return { results, pagination };

  // Method 3: Replacing a core service
  async findOne(entityId, params = {}) {
    return strapi.entityService.findOne('api::restaurant.restaurant', entityId, this.getFetchParams(params));

πŸ€“ Entity Service API

To get started creating your own services, see Strapi's built-in functions in the Entity Service API documentation.

Example of an email service

The goal of a service is to store reusable functions. An email service could be useful to send emails from different functions in our codebase:

// path: ./src/api/email/services/email.js

const { createCoreService } = require('@strapi/strapi').factories;
const nodemailer = require('nodemailer'); // Requires nodemailer to be installed (npm install nodemailer)

// Create reusable transporter object using SMTP transport.
const transporter = nodemailer.createTransport({
  service: 'Gmail',
  auth: {
    user: 'user@gmail.com',
    pass: 'password',

module.exports = createCoreService('api::email.email', ({ strapi }) => ({
  send(from, to, subject, text) {
    // Setup e-mail data.
    const options = {

    // Return a promise of the function that sends the email.
    return transporter.sendMail(options);

The service is now available through the strapi.service('api::email.email').send(...args) global variable. It can be used in another part of the codebase, like in the following controller:

// path: ./src/api/user/controllers/user.js

module.exports = createCoreController('api::restaurant.restaurant', ({ strapi }) =>  ({
  // GET /hello
  async signup(ctx) {
    const { userData } = ctx.body;

    // Store the new user in database.
    const user = await strapi.service('plugin::users-permissions.user').add(userData);

    // Send an email to validate his subscriptions.
    strapi.service('api::email.email').send('welcome@mysite.com', user.email, 'Welcome', '...');

    // Send response to the server.
      ok: true,


When a new content-type is created, Strapi builds a generic service with placeholder code, ready to be customized.

# Extending core services

Core services are created for each content-type and could be used by controllers to execute reusable logic through a Strapi project. Core services can be customized to implement your own logic. The following code examples should help you get started.

πŸ’‘ TIP

A core service can be replaced entirely by creating a custom service and naming it the same as the core service (e.g. find, findOne, create, update, or delete).

Collection type examples
Single type examples

# Usage

Once a service is created, it's accessible from controllers or from other services:

// access an API service
// access a plugin service

πŸ’‘ TIP

To list all the available services, run yarn strapi services:list.