Examples for the ElmRings Blog Post

historyExportFunction.js

handleHistoryExport(event) {
  const target = event.target;
  // see if we're downloading data from Elm 0.18.x
  // assuming that the history export format won't change in a patch version 🤞
  if (target.href && unescape(target.href).match(/{"elm":0.18/)) {
    // Elm delivers the data in the format
    // 'data:' + mime + ',' + encodeURIComponent(jsonString));
    const historyData = unescape(target.href.split(/,/)[1]);

    // you'll generally want to handle this data in Javascript, since nothing good would likely come from
    // putting an export of the Elm history back into the Elm history
    processHistoryData(historyData);

    // when triggered automatically, we don't want to harass the user with an unexpected download prompt
    // you may further want this to be always disabled, up to you
    if (!this.allowDownload) {
      event.preventDefault();
    }
    return this.allowDownload;
  }
}