BlobManager: implement Blob from ArrayBuffer

[CodyJasonBennett]

Summary:

Fixes a critical networking path used commonly in graphics code, among many other use-cases. It is commonplace to store images within a single binary such as a GLB (see KHR_binary_glTF). Base64 encoded glTF can be critically slow in older browsers with an increased size, so it's not a suitable fallback for those targeting multiple platforms. Furthermore, large base64 payloads can cause crash behavior on native when passed via JSI (e.g. expo-gl). For textures, this can be several megabytes of high precision data, and a uri from a blob is preferred rather than writing platform-specific workarounds via the filesystem.

A user-land patch I've employed in pmndrs/react-three-fiber, as well as existing user-land patches, is to test the Blob constructor with an empty ArrayBuffer. base64-js is used here since it's already installed with react-native for binary utils elsewhere. This is declared as a dependency in the linked library since this is an implementation detail, but will be de-duplicated at install time.

import { fromByteArray } from 'base64-js'

// Patch Blob for ArrayBuffer if unsupported
try {
  new Blob([new ArrayBuffer(4)])
} catch (_) {
  global.Blob = class extends Blob {
    constructor(parts, options) {
      super(
        parts?.map((part) => {
          if (part instanceof ArrayBuffer || ArrayBuffer.isView(part)) {
            part = fromByteArray(new Uint8Array(part))
          }

          return part
        }),
        options,
      )
    }
  }
}

Changelog:

[INTERNAL] [FIXED] - Implement Blob from ArrayBuffer

Test Plan:

Run the following at the project root to selectively test changes:

jest packages/react-native/Libraries/Blob

Note: base64 encoding will add an additional ~33% size increase to binary data as part of this PR. This is padded to 4 bytes so a byte length of 4 will encode as 8. Native ArrayBuffer support would not have this behavior and remove the overhead of base64 encoding back and forth. This is a growing behavior across the networking stack, such as in FileReader.

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[github-actions]

	Warnings
⚠️	One hour and a half have passed and the E2E jobs haven't finished yet.
⚠️	packages/react-native/Libraries/Blob/BlobManager.js#L11 - packages/react-native/Libraries/Blob/BlobManager.js line 11 – Requires should be sorted alphabetically (lint/sort-imports)

Generated by 🚫 dangerJS against 6498dbe

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[github-actions]

This pull request was successfully merged by @CodyJasonBennett in a228b0f.

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