@loaders.gl/compression/src/lib/lzo-compression.ts

Decompression and compression plugins for loaders.gl

// loaders.gl
// SPDX-License-Identifier: MIT
// Copyright (c) vis.gl contributors

// LZO
// import {loadLibrary} from '@loaders.gl/worker-utils';
import {registerJSModules, getJSModule, toBuffer} from '@loaders.gl/loader-utils';

import type {CompressionOptions} from './compression';
import {Compression} from './compression';
// import {isBrowser} from '@loaders.gl/loader-utils';

// import lzo from 'lzo'; // https://bundlephobia.com/package/lzo
// import {decompress} from 'lzo-wasm';

// const LZO_WASM_JS_URL = './node_modules/lzo-wasm/lzo-wasm.js';
// const LZO_WASM_WASM_URL = './node_modules/lzo-wasm/lzo-wasm.wasm';

/**
 * Lempel-Ziv-Oberheimer compression / decompression
 */
export class LZOCompression extends Compression {
  readonly name = 'lzo';
  readonly extensions = [];
  readonly contentEncodings = [];
  readonly isSupported = false; // !isBrowser;
  readonly options: CompressionOptions;

  /**
   * lzo is an injectable dependency due to big size
   * @param options
   */
  constructor(options: CompressionOptions) {
    super(options);
    this.options = options;
    registerJSModules(options?.modules);
  }

  async preload(modules: Record<string, any> = {}): Promise<void> {
    registerJSModules(modules);
    // await loadLibrary(LZO_WASM_JS_URL);
    // await loadLibrary(LZO_WASM_WASM_URL);
  }

  async compress(input: ArrayBuffer): Promise<ArrayBuffer> {
    await this.preload();
    const lzo = getJSModule('lzo', this.name);
    // const inputArray = new Uint8Array(input);
    const inputBuffer = toBuffer(input);
    return lzo.compress(inputBuffer).buffer;
  }

  async decompress(input: ArrayBuffer): Promise<ArrayBuffer> {
    try {
      await this.preload();
      const lzo = getJSModule('lzo', this.name);
      // const inputArray = new Uint8Array(input);
      const inputBuffer = toBuffer(input);
      return lzo.decompress(inputBuffer).buffer;
    } catch (error) {
      // TODO - solve SharedArrayBuffer issues
      // return decompress(input);
      throw error;
    }
  }
}