image-minimizer-webpack-plugin/dist/worker.js

Webpack loader and plugin to optimize (compress) images using imagemin

"use strict";

/** @typedef {import("./index").WorkerResult} WorkerResult */

/** @typedef {import("./index").FilenameFn} FilenameFn */

/**
 * @template T
 * @param {import("./index").InternalWorkerOptions<T>} options
 * @returns {Promise<WorkerResult>}
 */
async function worker(options) {
  /** @type {WorkerResult} */
  let result = {
    data: options.input,
    filename: options.filename,
    warnings: [],
    errors: [],
    info: {}
  };

  if (!result.data) {
    result.errors.push(new Error("Empty input"));
    return result;
  }
  /**
   * @param {WorkerResult} item
   * @param {undefined | string | FilenameFn} filename
   * @returns {WorkerResult}
   */


  const normalizeProcessedResult = (item, filename) => {
    if (!item.info) {
      item.info = {};
    }

    if (!item.filename) {
      item.filename = options.filename;
    }

    if (!item.errors) {
      item.errors = [];
    }

    if (!item.warnings) {
      item.warnings = [];
    }

    if (options.severityError === "off") {
      item.warnings = [];
      item.errors = [];
    } else if (options.severityError === "warning") {
      item.warnings = [...item.warnings, ...item.errors];
      item.errors = [];
    }

    if (typeof filename !== "undefined" && typeof options.generateFilename !== "undefined") {
      item.filename = options.generateFilename(filename, {
        filename: item.filename
      });
    }

    return item;
  };

  const transformers = Array.isArray(options.transformer) ? options.transformer : [options.transformer];

  for (let i = 0; i <= transformers.length - 1; i++) {
    if (transformers[i].filter && // @ts-ignore
    !transformers[i].filter(
    /** @type {Buffer} */
    options.input, options.filename)) {
      continue;
    }
    /** @type {WorkerResult} */


    let processedResult;

    try {
      // eslint-disable-next-line no-await-in-loop
      processedResult = await transformers[i].implementation(result, transformers[i].options);
    } catch (error) {
      result.errors.push(error instanceof Error ? error : new Error(
      /** @type {string} */
      error));
      return result;
    }

    if (!processedResult || !Buffer.isBuffer(processedResult.data)) {
      result.errors.push(new Error("minimizer function doesn't return the 'data' property or result is not a 'Buffer' value"));
      return result;
    }

    result = normalizeProcessedResult(processedResult, transformers[i].filename);
  }

  return result;
}

module.exports = worker;