71. soundcloud track downloader [downloader] [audio] [official api]

/*
  nama   : soundcloud track downloader
  base   : https://soundcloud.com
  by     : wolep
  update : 30 november 2025 1 PM
  node   : v24.11.1
  note   : idk, enjoy
  module : esm (tested) / cjs (gak tau coba test yah :v)
*/

const sc = {
    helper: {
        log: function (message) {
            //return
            console.log(`[scdl] ${message}`)
        },

        prettyError: function (string) {
            const MAX_LENGTH = 200
            const type = typeof (string)
            if (type !== "string") return `(gak bisa nampilin teks karena type yg di kasih adalah ${type})`
            if (!string) return '(empty message)'
            let message = string
            try {
                message = JSON.stringify(JSON.parse(string), null, 2)
            } catch (_) { }
            if (message.length > MAX_LENGTH) {
                message = message.substring(0, MAX_LENGTH) + `... (trimmed ${string.length - MAX_LENGTH} characters)`
            }
            return message
        }
    },

    static: {
        baseHeaders: {
            'accept-encoding': 'gzip, deflate, br, zstd',
            'user-agent': 'Mozilla/5.0 (iPhone; CPU iPhone OS 18_5 like Mac OS X) AppleWebKit/605.1.15 (KHTML, like Gecko) Version/18.5 Mobile/15E148 Safari/604.1'
        }
    },

    getTrackMetadata: async function (mobileUrl) {
        this.helper.log('get track metadata, client id, etc...')
        const r = await fetch(mobileUrl, { headers: this.static.baseHeaders })
        if (!r.ok) throw Error(`getTrackMetadata function. ${r.status} ${r.statusText}\n${this.helper.prettyError(await r.text())}`)
        const html = await r.text()
        const match = html.match(/__NEXT_DATA__" type="application\/json">(.+?)<\/script\>\</)?.[1]
        if (!match) throw Error('gagal mendapatkan track metadata')
        const json = JSON.parse(match)
        return json
    },

    toMobileUrl: function (trackUrl) {
        const url = new URL(trackUrl)
        if (!url.host.startsWith('m.')) url.host = 'm.' + url.host
        return url
    },

    getProgressiveUrl: async function (tmObj) {
        this.helper.log('get progressive url')

        const ctm = Object.entries(tmObj.props.pageProps.initialStoreState.entities.tracks)[0][1].data

        const purl = ctm.media.transcodings.find(a => a.format.protocol === 'progressive')?.url
        if (!purl) throw Error(`tidak menemukan progressive url`)

        const track_authorization = ctm.track_authorization

        const client_id = tmObj.runtimeConfig.clientId

        const url = new URL(purl)
        url.search = new URLSearchParams({
            client_id, track_authorization, 'stage': ''
        })
        const headers = this.static.baseHeaders

        const title = ctm.title
        const user = tmObj.head.find(p => p[1].name == 'twitter:audio:artist_name')?.[1]?.content
        const like = ctm.likes_count
        const comment = ctm.comment_count
        const imageUrl = ctm.artwork_url.replace('large', 't1080x1080') // gw makek fixed size 1080 ya haha

        const r = await fetch(url, {
            headers,
        });

        if (!r.ok) throw Error(`getProgressiveUrl function. ${r.status} ${r.statusText}\n${this.helper.prettyError(await r.text())}`)

        const json = await r.json()
        const audioUrl = json.url
        return {title, user, like, comment, imageUrl, audioUrl}
    },

    downloadTrack: async function (trackUrl) {
        const murl = this.toMobileUrl(trackUrl)
        const tmObj = await this.getTrackMetadata(murl)
        const result = await this.getProgressiveUrl(tmObj)
        this.helper.log('success')
        return result
    }
}

// cara pakai
sc.downloadTrack('https://soundcloud.com/nocopyrightsounds/sub-urban-cradles-ncs-release')
    .then(console.log)
    .catch(console.log)

/* output
{
  title: 'Sub Urban - Cradles [NCS Release]',
  user: 'NCS',
  like: 680710,
  comment: 30040,
  imageUrl: 'https://i1.......sid-t1080x1080.jpg',
  audioUrl: 'https://cf-media.sndcdn.com/P.....&Key-Pair-Id=APKAI6TU7MMXM5DG6EPQ'
}
*/

// export default sc