Download SoundCloud without external service + embed cover art into MP3 ID3 metadata.
此腳本不應該直接安裝，它是一個供其他腳本使用的函式庫。欲使用本函式庫，請在腳本 metadata 寫上： // @require https://update.gf.qytechs.cn/scripts/556576/1699828/Local%20SoundCloud%20Downloader%20%28with%20cover-%3EID3%29.js
// ==UserScript== // @name Local SoundCloud Downloader (with cover->ID3) // @namespace https://blog.maple3142.net/ // @version 0.2.1 // @description Download SoundCloud without external service + embed cover art into MP3 ID3 metadata. // @author maple3142 + modified by ChatGPT // @match https://soundcloud.com/* // @require https://cdn.jsdelivr.net/npm/[email protected]/dist/ponyfill.min.js // @require https://cdn.jsdelivr.net/npm/[email protected]/StreamSaver.min.js // @require https://cdn.jsdelivr.net/npm/[email protected]/dist/browser-id3-writer.min.js // @grant none // @license MIT // @icon https://a-v2.sndcdn.com/assets/images/sc-icons/favicon-2cadd14bdb.ico // @downloadURL https://update.greasyfork.org/scripts/394837/Local%20SoundCloud%20Downloader.user.js // @updateURL https://update.greasyfork.org/scripts/394837/Local%20SoundCloud%20Downloader.meta.js // ==/UserScript== /* jshint esversion: 8 */ streamSaver.mitm = "https://maple3142.github.io/StreamSaver.js/mitm.html"; function hook(obj, name, callback, type) { const fn = obj[name]; obj[name] = function (...args) { if (type === "before") callback.apply(this, args); fn.apply(this, args); if (type === "after") callback.apply(this, args); }; return () => { // restore obj[name] = fn; }; } function triggerDownload(url, name) { const a = document.createElement("a"); document.body.appendChild(a); a.href = url; a.download = name; a.click(); a.remove(); } const btn = { init() { this.el = document.createElement("button"); this.el.textContent = "Download"; this.el.classList.add("sc-button"); this.el.classList.add("sc-button-medium"); this.el.classList.add("sc-button-icon"); this.el.classList.add("sc-button-responsive"); this.el.classList.add("sc-button-secondary"); this.el.classList.add("sc-button-download"); }, cb() { const par = document.querySelector(".sc-button-toolbar .sc-button-group"); if (par && this.el.parentElement !== par) par.insertAdjacentElement("beforeend", this.el); }, attach() { this.detach(); this.observer = new MutationObserver(this.cb.bind(this)); this.observer.observe(document.body, { childList: true, subtree: true }); this.cb(); }, detach() { if (this.observer) this.observer.disconnect(); } }; btn.init(); function getClientId() { return new Promise((resolve) => { const restore = hook( XMLHttpRequest.prototype, "open", function (method, url) { const u = new URL(url, document.baseURI); const clientId = u.searchParams.get("client_id"); if (!clientId) return; console.log("got clientId", clientId); restore(); resolve(clientId); }, "after" ); }); } const clientIdPromise = getClientId(); let controller = null; // helper: try to build best artwork url function artworkBestUrl(track) { // track.artwork_url often contains e.g. -large.jpg ; try t500x500 or original; fallback to user avatar let art = track.artwork_url || (track.user && track.user.avatar_url) || null; if ( !art && track.publisher_metadata && track.publisher_metadata.artwork && track.publisher_metadata.artwork.url ) { art = track.publisher_metadata.artwork.url; } if (!art) return null; // replace size placeholders commonly used by SoundCloud return art.replace("-large", "-t500x500").replace("-crop", "-t500x500"); } // fetch arrayBuffer with simple error handling async function fetchArrayBuffer(url, signal) { const resp = await fetch(url, { signal }); if (!resp.ok) throw new Error("Fetch failed: " + resp.status); return resp.arrayBuffer(); } async function load(by) { btn.detach(); console.log("load by", by, location.href); if ( /^(\/(you|stations|discover|stream|upload|search|settings))/.test( location.pathname ) ) return; const clientId = await clientIdPromise; if (controller) { controller.abort(); controller = null; } controller = new AbortController(); const result = await fetch( `https://api-v2.soundcloud.com/resolve?url=${encodeURIComponent( location.href )}&client_id=${clientId}`, { signal: controller.signal } ) .then((r) => r.json()) .catch((e) => { console.warn("resolve failed", e); return {}; }); console.log("result", result); if (result.kind !== "track") return; btn.el.onclick = async () => { try { const progressive = result.media && result.media.transcodings && result.media.transcodings.find( (t) => t.format && t.format.protocol === "progressive" ); if (!progressive) { alert("Sorry, downloading this music is currently unsupported."); return; } // get the actual progressive audio URL const { url } = await fetch( progressive.url + `?client_id=${clientId}` ).then((r) => r.json()); // fetch audio as ArrayBuffer (required to write ID3) const audioBuf = await fetchArrayBuffer(url); // try to fetch artwork let coverBuf = null; const artUrl = artworkBestUrl(result); if (artUrl) { try { // SoundCloud sometimes returns SVG/other or redirects — let errors be caught coverBuf = await fetchArrayBuffer(artUrl); } catch (e) { console.warn("cover fetch failed", e); coverBuf = null; } } // Use browser-id3-writer to set tags // ID3Writer is provided by browser-id3-writer (required at top) let filename = (result.title || "track") + ".mp3"; // sanitize filename a bit filename = filename.replace(/[\/\\?%*:|"<>]/g, "_"); let taggedBlob = null; try { const writer = new ID3Writer(audioBuf); // Basic tags if (result.title) writer.setFrame("TIT2", result.title); if (result.user && result.user.username) writer.setFrame("TPE1", [result.user.username]); if ( result.publisher_metadata && result.publisher_metadata.album_title ) { writer.setFrame("TALB", result.publisher_metadata.album_title); } else if (result.title) { // optional: nothing } // add cover if available if (coverBuf) { // attempt to detect mime from first bytes (jpeg/png) let mime = "image/jpeg"; // default const dv = new Uint8Array(coverBuf); if (dv[0] === 0x89 && dv[1] === 0x50 && dv[2] === 0x4e) mime = "image/png"; writer.setFrame("APIC", { type: 3, data: coverBuf, description: "Cover", mime: mime }); } writer.addTag(); taggedBlob = writer.getBlob(); } catch (e) { console.warn("ID3 tagging failed, falling back to raw file", e); // if tagging failed, fallback to raw audio taggedBlob = new Blob([audioBuf], { type: "audio/mpeg" }); } // Attempt to save using StreamSaver (good for large files) // Note: StreamSaver supports streaming a blob stream to disk: taggedBlob.stream() try { const fileStream = streamSaver.createWriteStream(filename, { size: taggedBlob.size }); // Use readable stream from blob and pipe to streamSaver const readable = taggedBlob.stream(); if (readable.pipeTo) { await readable.pipeTo(fileStream); } else { // fallback: manual pump const reader = readable.getReader(); const writer = fileStream.getWriter(); const pump = () => reader .read() .then(({ done, value }) => done ? writer.close() : writer.write(value).then(pump) ); await pump(); } } catch (e) { // fallback to normal download via object URL console.warn("StreamSaver failed, fallback to anchor download", e); const urlObj = URL.createObjectURL(taggedBlob); triggerDownload(urlObj, filename); // release object URL after a while setTimeout(() => URL.revokeObjectURL(urlObj), 60 * 1000); } } catch (err) { console.error("Download failed", err); alert("Download error: " + (err.message || err)); } }; btn.attach(); console.log("attached"); } load("init"); hook(history, "pushState", () => load("pushState"), "after"); window.addEventListener("popstate", () => load("popstate"));
