backend restapi Overview

@quatrain/backend-restapi

A scalable and flexible backend adapter for integrating Quatrain applications with remote REST APIs.

Overview

This package provides RestBackendAdapter, which implements the AbstractBackendAdapter interface. It translates Quatrain's standard CRUD methods (create, read, update, delete, find) into RESTful HTTP requests using the @quatrain/api-client.

Features

• Configurable Endpoints: Map models directly to specific endpoints via endpointMap.
• Method Restrictions: Explicitly define allowedMethods to prevent unsupported CRUD actions.
• Dynamic Querying: Customize how Quatrain Filters and SortAndLimit map to query strings via the querySerializer.
• Authentication: Native support for Basic, Bearer, and generic OAuth via the API Client.

Basic Usage

import { RestBackendAdapter } from '@quatrain/backend-restapi'
import { BearerAuthProvider } from '@quatrain/api-client'

const restAdapter = new RestBackendAdapter({
   baseUrl: 'https://api.example.com/v1',
   endpointMap: {
      'User': '/users',
      'Post': '/posts'
   },
   allowedMethods: ['read', 'find', 'create'], // Disallow update/delete
   authProvider: new BearerAuthProvider('my-token'),
   querySerializer: (filters, pagination) => {
      // Custom filter mapping...
      return { offset: pagination?.limits.offset, limit: pagination?.limits.batch }
   }
})

// Use the adapter in your Backend initialization
Backend.init(restAdapter)

Extending

For complex integrations, you can extend the adapter:

class CustomRestAdapter extends RestBackendAdapter {
   protected buildUrl(collectionName: string, uid?: string): string {
      // Custom URL logic
      return super.buildUrl(collectionName, uid)
   }
}

Recipes

See the @quatrain/backend-restapi-recipes package for community-maintained query serializers for famous APIs (OpenWeatherMap, CoinGecko, etc.).

TODO

• Multi-Format Parsing: Evolve ApiClient to respect the responseType parameter (avoiding forced .json()) to allow ingesting CSV or XML payloads.
• Custom Response Parsers: Introduce a responseParser?: (rawResponse: any) => Record<string, any>[] in RestAdapterOptions to parse exotic formats into Quatrain-compatible objects.
• Hypertext API Navigation: Support HTML-based APIs by utilizing @quatrain/ai within the responseParser to extract JSON from unstructured web pages.