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@loopback/rest-crud

REST API controller implementing default CRUD semantics.

Overview

This module allows applications to quickly expose models via REST API without having to implement custom controller or repository classes.

Installation

npm install --save @loopback/rest-crud

Basic use

@loopback/rest-crud can be used along with the built-in ModelApiBooter to easily create a repository class and a controller class for your model. The following use is a simple approach for this creation, however, you can look at the “Advanced use” section instead for a more flexible approach.

For the examples in the following sections, we are assuming a model named Product and a datasource named db have already been created.

In your src/application.ts file:

// add the following import
import {CrudRestComponent} from '@loopback/rest-crud';

export class TryApplication extends BootMixin(
  ServiceMixin(RepositoryMixin(RestApplication)),
) {
  constructor(options: ApplicationConfig = {}) {
    // other code

    // add the following line
    this.component(CrudRestComponent);
  }
}

Create a new file for the configuration, e.g. src/model-endpoints/product.rest-config.ts that defines the model, pattern, dataSource, and basePath properties:

import {ModelCrudRestApiConfig} from '@loopback/rest-crud';
import {Product} from '../models';

module.exports = <ModelCrudRestApiConfig>{
  model: Product,
  pattern: 'CrudRest', // make sure to use this pattern
  dataSource: 'db',
  basePath: '/products',
};

Now your Product model will have a default repository and default controller class defined without the need for a repository or controller class file.

Advanced use

If you would like more flexibility, e.g. if you would only like to define a default CrudRest controller or repository, you can use the two helper methods (defineCrudRestController from @loopback/rest-crud and defineCrudRepositoryClass from @loopback/repository). These functions will help you create controllers and repositories using code.

For the examples in the following sections, we are also assuming a model named Product, and a datasource named db have already been created.

Creating a CRUD Controller

Here is how you would use defineCrudRestController for exposing the CRUD endpoints of an existing model with a respository.

  1. Create a REST CRUD controller class for your model.

    const ProductController = defineCrudRestController<
      Product,
      typeof Product.prototype.id,
      'id'
    >(Product, {basePath: '/products'});
    
  2. Set up dependency injection for the ProductController.

    inject('repositories.ProductRepository')(ProductController, undefined, 0);
    
  3. Register the controller with your application.

    app.controller(ProductController);
    

Creating a CRUD repository

Use the defineCrudRepositoryClass method to create named repositories (based on the Model) for your app.

Usage example:

import {defineCrudRepositoryClass} from '@loopback/repository';

const ProductRepository = defineCrudRepositoryClass(Product);
this.repository(ProductRepository);
inject('datasources.db')(ProductRepository, undefined, 0);

Integrated example

Here is an example of an app which uses defineCrudRepositoryClass and defineCrudRestController to fulfill its repository and controller requirements.

import {defineCrudRepositoryClass} from '@loopback/repository';

export class TryApplication extends BootMixin(
  ServiceMixin(RepositoryMixin(RestApplication)),
) {
  constructor(options: ApplicationConfig = {}) {
    // ...
  }

  async boot(): Promise<void> {
    await super.boot();

    const ProductRepository = defineCrudRepositoryClass(Product);
    const repoBinding = this.repository(ProductRepository);

    inject('datasources.db')(ProductRepository, undefined, 0);

    const ProductController = defineCrudRestController<
      Product,
      typeof Product.prototype.id,
      'id'
    >(Product, {basePath: '/products'});

    inject(repoBinding.key)(ProductController, undefined, 0);
    this.controller(ProductController);
  }
}

Contributions

Tests

Run npm test from the root folder.

Contributors

See all contributors.

License

MIT