Class AsyncPreloader

AsyncPreloader: assets preloader using ES2017 async/await and fetch.

It exports an instance of itself as default so you can:

import Preloader from "async-preloader";

await Preloader.loadItems([]);

to use directly as a singleton or

import { AsyncPreloader as Preloader } from "async-preloader";

const preloader = new Preloader();
await preloader.loadItems([]);

if you need more than one instance.

Hierarchy

AsyncPreloader

Constructors

constructor

new AsyncPreloader(): AsyncPreloader
Returns AsyncPreloader

Properties

defaultBodyMethod

defaultBodyMethod: BodyMethod = "blob"

Default body method to be called on the Response from fetch if no body option is specified on the LoadItem

defaultLoader

defaultLoader: LoaderKey = LoaderKey.Text

Default loader to use if no loader key is specified in the LoadItem or if the extension doesn't match any of the AsyncPreloader.loaders extensions

items

items: Map<string, LoadedValue> = ...

Object that contains the loaded items

`Static` `Private` domParser

domParser: DOMParser = ...

DOMParser instance for the XML loader

`Static` `Private` loaders

loaders: Map<LoaderKey, LoaderValue> = ...

Loader types and the extensions they handle

Allows the omission of the loader key in a LoadItem.loader for some generic extensions

Methods

loadArrayBuffer

loadArrayBuffer(item): Promise<ArrayBuffer>
Load an item and parse the Response as arrayBuffer
Parameters
- item: LoadItem
  Item to load
Returns Promise<ArrayBuffer>
Fulfilled value of parsed Response
- Defined in index.ts:169

loadAudio

loadAudio(item): Promise<LoadedValue>
Load an item in one of the following cases:
- item's "loader" option set as "Audio"
- item's "src" option extensions matching the loaders Map
- direct call of the method
Parameters
- item: LoadItem
  Item to load
Returns Promise<LoadedValue>
Fulfilled value of parsed Response according to the "body" option. Defaults to an HTMLAudioElement with a blob as srcObject or src.
- Defined in index.ts:283

loadBlob

loadBlob(item): Promise<Blob>
Load an item and parse the Response as blob
Parameters
- item: LoadItem
  Item to load
Returns Promise<Blob>
Fulfilled value of parsed Response
- Defined in index.ts:180

loadFont

loadFont(item): Promise<string | FontFace>
Load a font via FontFace or check a font is loaded via FontFaceObserver instance
Parameters
- item: LoadItem
  Item to load (id correspond to the font family name).
Returns Promise<string | FontFace>
Fulfilled value with FontFace instance or initial id if no src provided.
- Defined in index.ts:351

loadFormData

loadFormData(item): Promise<FormData>
Load an item and parse the Response as formData
Parameters
- item: LoadItem
  Item to load
Returns Promise<FormData>
Fulfilled value of parsed Response
- Defined in index.ts:191

loadImage

loadImage(item): Promise<LoadedValue>
Load an item in one of the following cases:
- item's "loader" option set as "Image"
- item's "src" option extensions matching the loaders Map
- direct call of the method
Parameters
- item: LoadItem
  Item to load
Returns Promise<LoadedValue>
Fulfilled value with a decoded HTMLImageElement instance of or a parsed Response according to the "body" option. Defaults to a decoded HTMLImageElement.
- Defined in index.ts:206

loadItem

loadItem(item): Promise<LoadedValue>
Load a single item
Parameters
- item: string | LoadItem
  Item to load
Returns Promise<LoadedValue>
Resolve when item is loaded, reject for any error
- Defined in index.ts:104

loadItems

loadItems(items): Promise<LoadedValue[]>
Load the specified manifest (array of items)
Parameters
- items: string[] | LoadItem[]
  Items to load
Returns Promise<LoadedValue[]>
Resolve when all items are loaded, reject for any error
- Defined in index.ts:92

loadJson

loadJson(item): Promise<JSON>
Load an item and parse the Response as json
Parameters
- item: LoadItem
  Item to load
Returns Promise<JSON>
Fulfilled value of parsed Response
- Defined in index.ts:158

loadManifest

loadManifest(src, key?): Promise<LoadedValue[]>
Load a manifest of items
Parameters
- src: string
  Manifest src url
- key: string = "items"
  Manifest key in the JSON object containing the array of LoadItem.
Returns Promise<LoadedValue[]>
- Defined in index.ts:128

loadText

loadText(item): Promise<string>
Load an item and parse the Response as text
Parameters
- item: LoadItem
  Item to load
Returns Promise<string>
Fulfilled value of parsed Response
- Defined in index.ts:147

loadVideo

loadVideo(item): Promise<LoadedValue>
Load an item in one of the following cases:
- item's "loader" option set as "Video"
- item's "src" option extensions matching the loaders Map
- direct call of the method
Parameters
- item: LoadItem
  Item to load
Returns Promise<LoadedValue>
Fulfilled value of parsed Response according to the "body" option. Defaults to an HTMLVideoElement with a blob as srcObject or src.
- Defined in index.ts:244

loadXml

loadXml(item): Promise<LoadedXMLValue>
Load an item in one of the following cases:
- item's "loader" option set as "Xml"
- item's "src" option extensions matching the loaders Map
- direct call of the method
Parameters
- item: LoadItem
  Item to load (need a mimeType specified or default to "application/xml")
Returns Promise<LoadedXMLValue>
Result of Response parsed as a document.
- Defined in index.ts:324

`Static` `Private` fetchItem

fetchItem(item): Promise<Response>
Fetch wrapper for LoadItem
Parameters
- item: LoadItem
  Item to fetch
Returns Promise<Response>
Fetch response
- Defined in index.ts:386

`Static` `Private` getFileBaseName

getFileBaseName(path): string
Get file base name
Parameters
- path: string
Returns string
- Defined in index.ts:424

`Static` `Private` getFileExtension

getFileExtension(path): string
Get file extension
Parameters
- path: string
Returns string
- Defined in index.ts:414

`Static` `Private` getFileName

getFileName(path): string
Get file name
Parameters
- path: string
Returns string
- Defined in index.ts:434

`Static` `Private` getLoaderKey

getLoaderKey(extension): LoaderKey
Retrieve loader key from extension (when the loader option isn't specified in the LoadItem)
Parameters
- extension: string
Returns LoaderKey
- Defined in index.ts:447

`Static` `Private` getMimeType

getMimeType(loaderKey, extension): DOMParserSupportedType
Retrieve mime type from extension
Parameters
- loaderKey: LoaderKey
- extension: string
Returns DOMParserSupportedType
- Defined in index.ts:461

`Static` `Private` getProp

getProp(object, path): any
Get an object property by its path in the form 'a[0].b.c' or ['a', '0', 'b', 'c']. Similar to lodash.get.
Parameters
- object: unknown
  Object with nested properties
- path: string | string[]
  Path to the desired property
Returns any
The returned object property
- Defined in index.ts:398

Class AsyncPreloader

Hierarchy

Index

Constructors

Properties

Methods

Constructors

constructor

Returns AsyncPreloader

Properties

defaultBodyMethod

defaultLoader

items

Static Private domParser

Static Private loaders

Methods

loadArrayBuffer

Parameters

item: LoadItem

Returns Promise<ArrayBuffer>

loadAudio

Parameters

item: LoadItem

Returns Promise<LoadedValue>

loadBlob

Parameters

item: LoadItem

Returns Promise<Blob>

loadFont

Parameters

item: LoadItem

Returns Promise<string | FontFace>

loadFormData

Parameters

item: LoadItem

Returns Promise<FormData>

loadImage

Parameters

item: LoadItem

Returns Promise<LoadedValue>

loadItem

Parameters

item: string | LoadItem

Returns Promise<LoadedValue>

loadItems

Parameters

items: string[] | LoadItem[]

Returns Promise<LoadedValue[]>

loadJson

Parameters

item: LoadItem

Returns Promise<JSON>

loadManifest

Parameters

src: string

key: string = "items"

Returns Promise<LoadedValue[]>

loadText

Parameters

item: LoadItem

Returns Promise<string>

loadVideo

Parameters

item: LoadItem

Returns Promise<LoadedValue>

loadXml

Parameters

item: LoadItem

Returns Promise<LoadedXMLValue>

Static Private fetchItem

Parameters

item: LoadItem

Returns Promise<Response>

Static Private getFileBaseName

Parameters

path: string

Returns string

Static Private getFileExtension

Parameters

path: string

`Static` `Private` domParser

`Static` `Private` loaders

`Static` `Private` fetchItem

`Static` `Private` getFileBaseName

`Static` `Private` getFileExtension

`Static` `Private` getFileName

`Static` `Private` getLoaderKey

`Static` `Private` getMimeType

`Static` `Private` getProp