ionic-cache-src

Ionic module for caching resources, works for any HTML tag, use storage and filesystem. Uses Ionic Storage so it supports IndexedDB, SQLite (Cordova), WebSQL

Basic Usage

• As Directive (html) change src to cacheSrc

  1<img cacheSrc="http://sample-videos.com/img/Sample-png-image-1mb.png"/>

  1<div cacheSrc="http://sample-videos.com/img/Sample-jpg-image-500kb.jpg"></div>

  1<video cacheSrc="http://sample-videos.com/video/mp4/240/big_buck_bunny_240p_1mb.mp4"></video>

• You can use a preload image while the resource is downloading. It works for any tag. By default it uses a predefined image.

  1<img [cacheSrc]="IMAGE_URL" [preImage]="PRELOAD_IMAGE_PATH" />

Installation

Via NPM

1$ npm install --save ionic-cache-src @ionic/storage --save

or Yarn

1$ yarn add ionic-cache-src @ionic/storage

• Afterwards, you need to import the IonicCacheSrcModule in your module:

1import { NgModule } from '@angular/core';
2import { IonicStorageModule } from '@ionic/storage';
3import { File } from '@ionic-native/file';
4import { FileTransfer } from '@ionic-native/file-transfer';
5
6import { IonicCacheSrcModule } from 'ionic-cache-src';
7
8@NgModule({
9    imports: [
10        ...
11        IonicStorageModule.forRoot(),
12        IonicCacheSrcModule
13    ],
14    providers: [
15        File,
16        FileTransfer,
17        ...
18    ]
19})
20export class YourModule {};

Dependencies

Make sure to install the following ionic modules and cordova plugins:

• IonicStorageModule
• File plugin
• FileTransfer plugin

Advanced Usage

• Your typescript file. Use cache or cacheAll methods to fetch resources. (Note: Just first time, resource is downloaded and saved in filesystem)

  1import { Component } from '@angular/core';
  2import { CacheSrcService } from 'ionic-cache-src';
  3
  4@Component({
  5    selector: 'home-page',
  6    templateUrl: 'home.html'
  7})
  8export class HomePage {
  9
  10    let paths: string[] = [];
  11
  12    constructor(private _cacheSrv: CacheSrcService) {
  13        let images = [
  14            'http://sample-videos.com/img/Sample-png-image-500kb.png'
  15            'http://sample-videos.com/img/Sample-png-image-1mb.png'
  16            'http://sample-videos.com/img/Sample-jpg-image-500kb.jpg'
  17        ];
  18
  19        // Use cache() for one resource
  20        this._cacheSrv.cacheAll(images)
  21            .subscribe(cacheItems => {
  22                this.paths = cacheItems.map(item => item.path);
  23            });
  24    }
  25    
  26}

• Your html file

  1<img *ngFor="let path of paths" [cacheSrc]="path"/>

Instance Members

- cache(url)

If not exists, saves a resource in storage and filesystem, otherwise, returns the saved item.

Param	Type	Description
url	string	URL of the server to download the file, as encoded by encodeURI().

• Return Observable<CacheItem>

- cacheAll(urls)

Gets a list of resources and evaluates which of them not exists in storage and filesystem and starts download. Otherwise, returns all the saved items.

Param	Type	Description
urls	string[]	List of URLs of the server to download the file, as encoded by encodeURI().

• Return Observable<CacheItem[]>

- find(url)

Returns a value of the first item in storage and filesystem that satisfies the provided url. Otherwise null is returned.

Param	Type	Description
url	string	URL of the server to download the file, as encoded by encodeURI().

• Return Observable<CacheItem>

- remove(url)

Removes any item associated with this url. Returns the deleted item with status "deleted".

Param	Type	Description
url	string	URL of the server to download the file, as encoded by encodeURI().

• Return Observable<CacheItem>

- clear()

Clears the entire ionic-cache-src storage and filesystem. Returns a list of items with status 'deleted'.

• Return Observable<CacheItem[]>

CacheItem

Param	Type	Description
url	string	URL from where it was downloaded.
key	string	Name of the saved file.
path	string	File path of the saved resource.
status	string	Shows "incomplete" while resource is downloading, "complete" once it is saved.

Supported Platforms

This module works with Ionic Framework (v >= 2.0), the supported platforms being:

• Android
• iOS

Contribution

• Having an issue? or looking for support? Open an issue and we will get you the help you need.

Support this project

If you find this project useful, please star the repo to let people know that it's reliable. Also, share it with friends and colleagues that might find this useful as well. Thank you :smile: