UpChunk
UpChunk uploads chunks of files! It's a JavaScript module for handling large file uploads via chunking and making a put
request for each chunk with the correct range request headers. Uploads can be paused and resumed, they're fault tolerant,
and it should work just about anywhere.
UpChunk is designed to be used with Mux direct uploads, but should work with any server that supports resumable uploads in the same manner. This library will:
- Split a file into chunks (in multiples of 256KB).
- Make a
PUT
request for each chunk, specifying the correctContent-Length
andContent-Range
headers for each one. - Retry a chunk upload on failures.
- Allow for pausing and resuming an upload.
Installation
NPM
npm install --save @mux/upchunk
Yarn
yarn add @mux/upchunk
Script Tags
<script src="https://unpkg.com/@mux/upchunk@2"></script>
Basic Usage
Getting an upload URL from Mux.
You'll need to have a route in your application that returns an upload URL from Mux. If you're using the Mux Node SDK, you might do something that looks like this.
const Mux = require('@mux/mux-node');
const { Video } = new Mux();
module.exports = async (req, res) => {
// This ultimately just makes a POST request to https://api.mux.com/video/v1/uploads with the supplied options.
const upload = await Video.Uploads.create({
cors_origin: 'https://your-app.com',
new_asset_settings: {
playback_policy: 'public',
},
});
// Save the Upload ID in your own DB somewhere, then
// return the upload URL to the end-user.
res.end(upload.url);
};
Then, in the browser with plain Javascript
import * as UpChunk from '@mux/upchunk';
// Pretend you have an HTML page with an input like: <input id="picker" type="file" />
const picker = document.getElementById('picker');
picker.onchange = () => {
const getUploadUrl = () =>
fetch('/the-endpoint-above').then(res =>
res.ok ? res.text() : throw new Error('Error getting an upload URL :(')
);
const upload = UpChunk.createUpload({
endpoint: getUploadUrl,
file: picker.files[0],
chunkSize: 30720, // Uploads the file in ~30 MB chunks
});
// subscribe to events
upload.on('error', err => {
console.error('💥 🙀', err.detail);
});
upload.on('progress', progress => {
console.log(`So far we've uploaded ${progress.detail}% of this file.`);
});
upload.on('success', () => {
console.log("Wrap it up, we're done here. 👋");
});
};
Or, in the browser with React
import React, { useState } from 'react';
import * as UpChunk from '@mux/upchunk';
function Page() {
const [progress, setProgress] = useState(0);
const [statusMessage, setStatusMessage] = useState(null);
const handleUpload = async (inputRef) => {
try {
const response = await fetch('/your-server-endpoint', { method: 'POST' });
const url = await response.text();
const upload = UpChunk.createUpload({
endpoint: url, // Authenticated url
file: inputRef.files[0], // File object with your video file’s properties
chunkSize: 30720, // Uploads the file in ~30 MB chunks
});
// Subscribe to events
upload.on('error', error => {
setStatusMessage(error.detail);
});
upload.on('progress', progress => {
setProgress(progress.detail);
});
upload.on('success', () => {
setStatusMessage("Wrap it up, we're done here. 👋");
});
} catch (error) {
setErrorMessage(error);
}
}
return (
<div className="page-container">
<h1>File upload button</h1>
<label htmlFor="file-picker">Select a video file:</label>
<input type="file" onChange={(e) => handleUpload(e.target)}
id="file-picker" name="file-picker"/ >
<label htmlFor="upload-progress">Downloading progress:</label>
<progress value={progress} max="100"/>
<em>{statusMessage}</em>
</div>
);
}
export default Page;
API
createUpload(options)
Returns an instance of UpChunk
and begins uploading the specified File
.
options
object parameters
-
endpoint
type:string
|function
(required)URL to upload the file to. This can be either a string of the authenticated URL to upload to, or a function that returns a promise that resolves that URL string. The function will be passed the
file
as a parameter. -
file
type:File
(required)The file you'd like to upload. For example, you might just want to use the file from an input with a type of "file".
-
headers
type:Object
|function
An object, a function that returns an object, or a function that returns a promise of an object. The resulting object contains any headers you'd like included with the
PUT
request for each chunk. -
chunkSize
type:integer
, default:30720
The size in kB of the chunks to split the file into, with the exception of the final chunk which may be smaller. This parameter must be in multiples of 256.
-
maxFileSize
type:integer
The maximum size of the file in kb of the input file to be uploaded. The maximum size can technically be smaller than the chunk size, and in that case there would be exactly one chunk.
-
attempts
type:integer
, default:5
The number of times to retry any given chunk.
-
delayBeforeAttempt
type:integer
, default:1
The time in seconds to wait before attempting to upload a chunk again.
-
method
type:"PUT" | "PATCH" | "POST"
, default:PUT
The HTTP method to use when uploading each chunk.
-
dynamicChunkSize
type:boolean
, default:false
Whether or not the system should dynamically scale the
chunkSize
up and down to adjust to network conditions. -
maxChunkSize
type:integer
, default:512000
When
dynamicChunkSize
istrue
, the largest chunk size that will be used, in kB. -
minChunkSize
type:integer
, default:256
When
dynamicChunkSize
istrue
, the smallest chunk size that will be used, in kB.
UpChunk Instance Methods
-
pause()
Pauses an upload after the current in-flight chunk is finished uploading.
-
resume()
Resumes an upload that was previously paused.
-
abort()
The same behavior as
pause()
, but also aborts the in-flight XHR request.
UpChunk Instance Events
Events are fired with a CustomEvent
object. The detail
key is null if an interface isn't specified.
-
attempt
{ detail: { chunkNumber: Integer, chunkSize: Integer } }
Fired immediately before a chunk upload is attempted.
chunkNumber
is the number of the current chunk being attempted, andchunkSize
is the size (in bytes) of that chunk. -
attemptFailure
{ detail: { message: String, chunkNumber: Integer, attemptsLeft: Integer } }
Fired when an attempt to upload a chunk fails.
-
chunkSuccess
{ detail: { chunk: Integer, attempts: Integer, response: XhrResponse } }
Fired when an indvidual chunk is successfully uploaded.
-
error
{ detail: { message: String, chunkNumber: Integer, attempts: Integer } }
Fired when a chunk has reached the max number of retries or the response code is fatal and implies that retries should not be attempted.
-
offline
Fired when the client has gone offline.
-
online
Fired when the client has gone online.
-
progress
{ detail: [0..100] }
Fired continuously with incremental upload progress. This returns the current percentage of the file that's been uploaded.
-
success
Fired when the upload is finished successfully.
FAQ
How do I cancel an upload?
Our typical suggestion is to use pause()
or abort()
, and then clean up the UpChunk instance however you'd like. For example, you could do something like this:
// upload is an UpChunk instance currently in-flight
upload.abort();
// In many cases, just `abort` should be fine assuming the instance will get picked up by garbage collection
// If you want to be sure, you can manually delete the instance.
delete upload;
Credit
The original idea for this came from the awesome huge uploader project, which is what you need if you're looking to do multipart form data uploads.
Also, @gabrielginter ported upchunk to Flutter.