parseUrlQuery() Snippet - Parse URL query parameters.

parseUrlQuery.js

function parseUrlQuery(queryString) {
  if (queryString.includes("=")) {
    return JSON.stringify(
      queryString.replace(/\+/g, '%20').split('&').reduce((dict, x) => {
          var parts = x.split('=', 2);
          dict[decodeURIComponent(parts[0])] = decodeURIComponent(parts[1]) || null;
          return dict;
      }, {}),
      null, // No replacer
      2 // indent with 2 spaces
    );
  }
  return "";
}

~io-config.jsonc

{
  // Where the JS code lies
  "files": ["parseUrlQuery.js"],
  // Name of the function responsable for transforming the input into the output.
  "transform": "parseUrlQuery",
  // Input setup
  "input": { "language": "text", "label": "Query String" },
  // Output setup
  "output": { "language": "json", "label": "Resulting Parameters" },
  // Type of YourJS IO-App
  "type": "split"
}

Here is the corresponding IO App:
https://yourjs.com/gist-io/926e337baa74b931a156ab1f1e7f3b14