tus-js-client-stall-detection/lib/commonFileReader.ts

A pure JavaScript client for the tus resumable upload protocol (fork with stall detection)

import type { FileSource, UploadInput } from './options.js'
import { ArrayBufferViewFileSource } from './sources/ArrayBufferViewFileSource.js'
import { BlobFileSource } from './sources/BlobFileSource.js'
import { WebStreamFileSource } from './sources/WebStreamFileSource.js'

/**
 * openFile provides FileSources for input types that have to be handled in all environments,
 * including Node.js and browsers.
 */
export function openFile(input: UploadInput, chunkSize: number): FileSource | null {
  // File is a subtype of Blob, so we only check for Blob here.
  // Note: We could turn Blobs into ArrayBuffers using `input.arrayBuffer()` and then
  // pass it to the ArrayBufferFileSource. However, in browsers, a File instance can
  // represent a file on disk. By keeping it a File instance and passing it to XHR/Fetch,
  // we can avoid reading the entire file into memory.
  if (input instanceof Blob) {
    return new BlobFileSource(input)
  }

  // ArrayBufferViews can be TypedArray (e.g. Uint8Array) or DataView instances.
  // Note that Node.js' Buffers are also Uint8Arrays.
  if (ArrayBuffer.isView(input)) {
    return new ArrayBufferViewFileSource(input)
  }

  // SharedArrayBuffer is not available in all browser context for security reasons.
  // Hence we check if the constructor exists at all.
  if (
    input instanceof ArrayBuffer ||
    (typeof SharedArrayBuffer !== 'undefined' && input instanceof SharedArrayBuffer)
  ) {
    const view = new DataView(input)
    return new ArrayBufferViewFileSource(view)
  }

  if (input instanceof ReadableStream) {
    chunkSize = Number(chunkSize)
    if (!Number.isFinite(chunkSize)) {
      throw new Error(
        'cannot create source for stream without a finite value for the `chunkSize` option',
      )
    }

    return new WebStreamFileSource(input)
  }

  return null
}

export const supportedTypes = [
  'File',
  'Blob',
  'ArrayBuffer',
  'SharedArrayBuffer',
  'ArrayBufferView',
  'ReadableStream (Web Streams)',
]