You don't absolutely need to have @prose-reader/core-streamer installed to run the reader but the utilities provided are very useful to standardize and feed books to the engine. rxjs is a peer-dependency of prose-reader and needs to be installed alongside.
Create your reader & load your book
On your html file you need to define a container for the reader. We will be using a full screen reader but you can have any dimensions.
The next step is to create a streamer and load our book into the reader. There is a lot of comment on purpose to help you understand the basic flow but in the end the code is rather simple.
There is a lot of comments in the code to explain the basic but the bootstrap and use of the SDK is fairly simple.
We are gonna use an epub as example so you should also install jszip
index.ts
You should now see the book being displayed.
Explore the next sections to see how to add functionalities such as navigating, gestures, etc.
import { createReader } from "@prose-reader/core"
import { createArchiveFromJszip, Streamer } from "@prose-reader/streamer"
import { from } from "rxjs"
import { loadAsync } from "jszip"
async function createStreamer() {
/**
* We create a streamer to load and serve our archive.
*
* A streamer is a convenient way to fetch manifest and resources from an archive.
* This will be used to feed information to the reader.
*
* For simplicity we use a web reader but we have a ServiceWorkerStreamer class
* that can and should be used whenever possible. This will offload the work from
* the main thread.
*/
const streamer = new Streamer({
getArchive: async () => {
/**
* First you need to fetch your book.
* It can be from anywhere, local, remote, etc.
*/
const epubResponse = await fetch("http://localhost:3000/accessible_epub_3.epub")
const epubBlob = await epubResponse.blob()
/**
* Because epubs are zip archives, we are gonna use jszip to manage them.
* You could use a different library but we provide helpers to deal with
* jszip formats as a convenience.
*/
const epubJszip = await loadAsync(epubBlob)
/**
* We are gonna use prose streamer to manage the epub.
* The streamer work with archives, so we need to create one from the epub.
*
* An archive is a higher level interface that is agnostic to the underlying
* format so the streamer can manage different formats transparently.
*
* We do provide several helpers to create archives from different formats.
* Epubs being zip archives, we have a helper that create an archive from a
* jszip object.
*/
const archive = await createArchiveFromJszip(epubJszip)
return archive
},
/**
* You can configure the streamer to let it know how long it should
* keep an archive in memory for example. When the archive is no longer available
* the getArchive callback will be called again.
*/
cleanArchiveAfter: 5 * 60 * 1000,
})
return streamer
}
async function run() {
const streamer = await createStreamer()
const manifestResponse = await streamer.fetchManifest({
/**
* The streamer is designed to manage several archives that's why
* it requires a key to be passed to identify which archive to use.
*
* In this case we only have one archive so we can use `_` as key.
*/
key: `_`,
})
const manifest = await manifestResponse.json()
const reader = createReader({
/**
* A manifest provide a list of resources and their URIs.
*
* However we are loading the epub locally in memory here so the items cannot be
* fetched directly. This would be possible and encouraged if using a service worker
* but in our situation we have to hook into the reader to tell him to get its resources
* from our local streamer directly.
*
* This may seems boilerplaty but the separation between the reader and the streamer is what
* makes prose very flexible and powerful.
*
* You can pretty much load anything in any way you want.
*
* We tried to create streamers that simplify the friction as much as possible.
*/
getResource: (item) => {
return from(streamer.fetchResource({ key: `_`, resourcePath: item.href }))
},
})
/**
* Finally we can load the reader with our manifest.
*/
reader.load({
containerElement: document.getElementById(`app`)!,
manifest,
})
}
run()