Source: inline.js

  1. /**
  2.  * This module provides utilities for working with inlined content.
  3.  * 
  4.  * @module inline
  5.  */
  7. /**
  8.  * Extract the content from a data URL as a string, decoding it from Base64
  9.  * if necessary. Useful for working with content scripts that have been
  10.  * encoded with `@rollup/plugin-url`.
  11.  * @param {string} dataUrl - The data URL.
  12.  * @returns {string} - The content of the URL.
  13.  */
  14. export function dataUrlToString(dataUrl) {
  15.     if(!dataUrl.startsWith("data:")) {
  16.         throw new Error("Incorrectly formatted data URL.");
  17.     }
  18.     const commaIndex = dataUrl.indexOf(",");
  19.     if(commaIndex < 0) {
  20.         throw new Error("Incorrectly formatted data URL.");
  21.     }
  22.     // Not currently checking that the MIME type is valid
  23.     const dataUrlMimeTypeAndEncoding = dataUrl.substring(0, commaIndex);
  24.     let content = dataUrl.substring(commaIndex + 1, dataUrl.length);
  25.     if(dataUrlMimeTypeAndEncoding.endsWith("base64")) {
  26.         content = atob(content);
  27.     }
  28.     return content;
  29. }
  31. /**
  32.  * Convert a data URL to a blob object URL. Useful for working with HTML
  33.  * documents that have been encoded with `@rollup/plugin-url`.
  34.  * @param {*} dataUrl - The data URL.
  35.  * @returns {string} - A blob object URL.
  36.  */
  37. export function dataUrlToBlobUrl(dataUrl) {
  38.     return URL.createObjectURL(new Blob([ dataUrlToString(dataUrl) ]));
  39. }