react-native-offline-api

Simple, customizable, offline-first API wrapper for react-native.

Easily write offline-first react-native applications with your own REST API. This module supports every major features for network requests : middlewares, fine-grained control over caching logic, custom caching driver...

Table of contents

• react-native-offline-api
  • Table of contents
  • Installation
  • How it works
  • How to use
    • Setting up your global API options
    • Declaring your services definitions
    • Firing your first request
  • Methods
  • API options
  • Services options
  • Fetch options
  • Path and query parameters
  • Limiting the size of your cache
  • Middlewares
  • Using your own driver for caching
  • Types

Installation

npm install --save react-native-offline-api # with npm
yarn add react-native-offline-api # with yarn

How it works

How to use

Since this plugin is a fully-fledged wrapper and not just a network helper, you need to set up your API configuration.

Setting up your global API options

Here's an example :

const API_OPTIONS = {
    domains: { default: 'http://myapi.tld', staging: 'http://staging.myapi.tld' },
    prefixes: { default: '/api/v1', apiV2: '/api/v2' },
    debugAPI: true,
    printNetworkRequests: true
};

Here, we have set up the wrapper so it can use 2 different domains, a production API (the default one) and a staging API.

We also have 2 different prefixes, so, if you're versioning your APIs by appending /v2 in your URLs for example, you'll be able to easily request each versions. Please note that this is totally optional.

Check out all the API options here

Declaring your services definitions

From now on, we'll call all your API's endpoint services. Now that you have set up your options, you need to declare your services. Easy peasy :

const API_SERVICES = {
  articles: {
    path: 'articles',
  },
  documents: {
    domain: 'staging',
    prefix: 'apiV2',
    path: 'documents/:documentId',
    disableCache: true
  },
  login: {
    path: 'login',
    method: 'POST',
    expiration: 5 * 60 * 1000
  }
};

Here, we declared 3 services :

• articles that will fetch data from http://myapi.tld/api/v1/articles
• documents that will fetch data from http://staging.myapi.tld/api/v2/documents/:documentId and won't cache anything
• login that will make a POST request on http://myapi.tld/api/v1/login with a 5 minutes caching

These are just examples, there are much more options for your services, check them out here.

Firing your first request

Now that we have our API options and services configured, let's call our API !

import React, { Component } from 'react';
import OfflineFirstAPI from 'react-native-offline-api';

// ... API and services configurations

const api = new OfflineFirstAPI(API_OPTIONS, API_SERVICES);

export default class demo extends Component {

    componentDidMount () {
        this.fetchSampleData();
    }

    async fetchSampleData () {
        try {
            const request = await api.fetch(
                'documents',
                {
                    pathParameters: { documentId: 'xSfdk21' }
                }
            );
            console.log('Our fetched document data', request);
        } catch (err) {
            // Handle any error
        }
    }

    render () {
        // ...
    }
}

In this short example, we're firing a GET request on the path http://staging.myapi.tld/api/v2/documents/xSfdk21. If you don't understand how this path is constructed, see path and query parameters.

A couple of notes :

• The fetch and fetchHeaders methods are promises, which means you can either use async/await or fetch().then().catch() if you prefer.
• You can instantiate OfflineFirstAPI without API_OPTIONS and/or API_SERVICES and set them later with api.setOptions and api.setServices methods if the need arises.

Methods

Name | Description | Parameters | Return value ------ | ------ | ------ | ------ fetch | Fires a network request to one of your service with additional options, see fetch options | service: string, options?: IFetchOptions | Promise<any> get, post, head... | Each HTTP method has a dedicated method that acts just like fetch | service: string, options?: IFetchOptions | Promise<any> fetchHeaders | Just like fetch but only returns the HTTP headers of the reponse | service: string, options?: IFetchOptions | Promise<any> clearCache | Clears all the cache, or just the one of a specific service | service?: string | Promise<void> setOptions | Sets or update the API options of the wrapper | options: IAPIOptions | void setServices | Sets or update your services definitions | services: IAPIServices | void setCacheDriver | Sets or update your custom cache driver, see using your own driver for caching | driver: IAPIDriver | void

API options

These are the global options for the wrapper. Some of them can be overriden at the service definition level, or with the option parameter of the fetch method. Only domains and prefixes are required.

Key | Type | Description | Example ------ | ------ | ------ | ------ domains | { default: string, [key: string]: string } | Required, full URL to your domains | domains: {default: 'http://myapi.tld', staging: 'http://staging.myapi.tld' }, prefixes | { default: string, [key: string]: string } | Required, prefixes your API uses, default is required, leave it blank if you don't have any | { default: '/api/v1', apiV2: '/api/v2' } middlewares | APIMiddleware[] | Optionnal middlewares, see middlewares | [authFunc, trackFunc] responseMiddleware | ResponseMiddleware | Optionnal middleware to alter your API responses, see middlewares | alterFunction debugAPI | boolean | Optional, enables debugging mode, printing what's the wrapper doing printNetworkRequests | boolean | Optional, prints all your network requests disableCache | boolean | Optional, completely disables caching (overriden by service definitions & fetch's option parameter) cacheExpiration | number | Optional default expiration of cached data in ms (overriden by service definitions & fetch's option parameter) cachePrefix | string | Optional, prefix of the keys stored on your cache, defaults to offlineApiCache ignoreHeadersWhenCaching | boolean | Optional, your requests will be cached independently from the headers you sent. Defaults to false capServices | boolean | Optional, enable capping for every service, defaults to false, see limiting the size of your cache capLimit | number | Optional quantity of cached items for each service, defaults to 50, see limiting the size of your cache offlineDriver | IAPIDriver | Optional, see use your own driver for caching

Services options

These are the options for each of your services, the only required key is path. Default values are supplied for the others.

Key | Type | Description | Example ------ | ------ | ------ | ------ path | string | Required path to your endpoint, see path and query parameters | article/:articleId expiration | number | Optional time in ms before this service's cached data becomes stale, defaults to 5 minutes method | GET | Optional HTTP method of your request, defaults to GET | OPTIONS... domain | string | Optional specific domain to use for this service, provide the key you set in your domains API option prefix | string | Optional specific prefix to use for this service, provide the key you set in your prefixes API option middlewares | APIMiddleware[] | Optional array of middlewares that override the ones set globally in your middlewares API option, see middlewares responseMiddleware | ResponseMiddleware | Optionnal middleware to alter your API responses that override the one set globally in your middlewares API option, see middlewares | alterFunction disableCache | boolean | Optional, disables the cache for this service (override your API's global options) capService | boolean | Optional, enable or disable capping for this specific service, see limiting the size of your cache capLimit | number | Optional quantity of cached items for this specific service, defaults to 50, see limiting the size of your cache ignoreHeadersWhenCaching | boolean | Optional, your requests will be cached independently from the headers you sent. Defaults to false rawData | boolean | Disables JSON parsing from your network requests, useful if you want to fetch XML or anything else from your api

Fetch options

The options parameter of the fetch and fetchHeaders method overrides the configuration you set globally in your API options, and the one you set for your services definitions. For instance, this is a good way of making very specific calls without having to declare another service just to tweak a single option.

Important notes :

• All of these are optional.
• All the keys of services options can be overriden here ! You could disable caching just for a single call for example, but still having it enabled in your service's definition.

Key | Type | Description | Example ------ | ------ | ------ | ------ pathParameters | { [key: string]: string } | Parameters to replace in your path, see path and query parameters | { documentId: 'xSfdk21' } queryParameters | { [key: string]: string } | Query parameters that will be appended to your service's path, , see path and query parameters | { refresh: true, orderBy: 'date' } headers | { [key: string]: string } | HTTP headers you need to pass in your request middlewares | APIMiddleware[] | Optional array of middlewares that override the ones set globally in your middlewares API option and in your service's definition, , see middlewares responseMiddleware | ResponseMiddleware | Optionnal middleware to alter your API responses that override the one set globally in your middlewares API option and in your service's definition, see middlewares | alterFunction fetchOptions | any | Optional, any value passed here will be merged into the options of react-native's fetch method so you'll be able to configure anything not provided by the wrapper itself

Path and query parameters

The URL to your endpoints are being constructed with your domain name, your optional prefix, and your optional pathParameters and queryParameters.

• The pathParameters will replace the parameters in your service's path. For instance, a request fired with this path : /documents/:documentId, and these pathParameters : { documentId: 'xSfdk21' } will become /documents/xSfdk21.

• The queryParameters are regular query string parameters. For instance, a request fired with this path : /weather and these queryParameters : { days: 'mon,tue,sun', location: 'Paris,France' } will become /weather?days=mon,tue,sun&location=Paris,France.

💡 Pro-tip : Both query and path parameters can be undefined, in this case they simply won't be processed when generating your route. You don't have to create an intermediate variable holding your options to handle whether or not your variables are defined.

Limiting the size of your cache

Learn more about enabling capping in the documentation

Middlewares

Check out middlewares documentation and examples

Using your own driver for caching

💡 You can now use SQLite instead of AsyncStorage without additional code !

Check out drivers documentation and how to enable the SQLite driver

Types

Every API interfaces can be seen here so you don't need to poke around the parameters in your console to be aware of what's available to you :)

💡 These are Typescript defintions, so they should be displayed in your editor/IDE if it supports it.