post-process.js

// ==UserScript==
// @name         Deluge post-process button
// @namespace    http://tampermonkey.net/
// @version      0.1
// @description  Adds a 'post-process' button that queues the currently selected torrent for post-processing.
// @author       You
// @match        https://example.com/
// @grant        none
// ==/UserScript==

window.addEventListener('load', function() {
    const root = document.querySelector('#connectionman').parentElement.parentElement

    function getActiveTorrents() {
        var selectedTorrents = window.deluge.torrents.selModel.selections.items
        return selectedTorrents.map(selectedTorrent => ({
            hash: selectedTorrent.id,
            name: selectedTorrent.data.name,
            path: selectedTorrent.data.download_location,
            label: selectedTorrent.data.label
        }))
    }

    function addPostProcessButton() {
        var button = document.querySelector('#post-process-button')
        if (!button) {
            var td = document.createElement('td')
            td.id = "ext-gen67"
            td.className = "x-toolbar-cell"
            td.innerHTML = `
  <table id="connectionman" cellspacing="0" class="x-btn x-btn-text-icon" style="width: auto;">
    <tbody class="x-btn-small x-btn-icon-small-left">
      <tr>
        <td class="x-btn-tl"><i>&nbsp;</i></td><td class="x-btn-tc"></td>
        <td class="x-btn-tr"><i>&nbsp;</i></td>
      </tr>
      <tr>
        <td class="x-btn-ml"><i>&nbsp;</i></td>
        <td class="x-btn-mc">
          <em class=" x-unselectable" unselectable="on">
            <button type="button" id="post-process-button" class=" x-btn-text x-deluge-connection-manager">Post-process</button>\
          </em>
        </td>
        <td class="x-btn-mr"><i>&nbsp;</i></td>
      </tr>
      <tr>
        <td class="x-btn-bl"><i>&nbsp;</i></td>
        <td class="x-btn-bc"></td>
        <td class="x-btn-br"><i>&nbsp;</i></td>
      </tr>
    </tbody>
  </table>
`
            root.appendChild(td)
            button = document.querySelector('#post-process-button')
        }

        button.removeEventListener('click', onPostProcessButtonClick)
        button.addEventListener('click', onPostProcessButtonClick, false)
    }

    async function onPostProcessButtonClick(evt) {
        var responses = getActiveTorrents().map(async torrent => {
            const response = await fetch("/post-process", {
                method: "POST",
                body: JSON.stringify(torrent),
                headers: { "content-type": "application/json" },
                credentials: "include"
            });
            console.log(response)
            return response
        })
        console.log(`processed ${responses.length} torrents`)
    }

    addPostProcessButton();
}, false);