Overview

The Audio Mixer allows you to play secondary audio tracks simultaneously with the main track. This is perfect for:

• Voiceovers & TTS: Announce song names or read chat messages without stopping the music.
• Sound Effects: Play airhorns, applause, or memes over the active track.
• Background Music: Keep a low-volume ambient track running while playing other media.

The mixer works by intercepting the main audio stream and digitally mixing the PCM data from auxiliary sources before encoding. It features intelligent buffering to handle sources that download faster than real-time (like TTS) and automatic clamping to prevent audio distortion.

Endpoints

The mixer exposes a full REST API for managing layers:

• POST /v4/sessions/:sessionId/players/:guildId/mix - Add a new layer
• GET /v4/sessions/:sessionId/players/:guildId/mix - List active layers
• PATCH /v4/sessions/:sessionId/players/:guildId/mix/:mixId - Update layer volume
• DELETE /v4/sessions/:sessionId/players/:guildId/mix/:mixId - Remove a layer

WebSocket Events

Overview

NodeLink supports high-fidelity volume fading to prevent jarring audio clips. This can be configured globally or per-request in the player update payload.

Configuration Structure

The fading object contains settings for different scenarios:

• trackStart: Fade in when a new track begins.
• trackEnd: Fade out as a track reaches its end.
• trackStop: Fade out when playback is stopped.
• seek: Fade out before and fade in after a seek operation.
• ducking: Lower volume temporarily (e.g., during a mix layer).

Each section accepts:

• duration: Time in milliseconds.
• curve: Mathematical curve for the fade (linear, exponential, logarithmic, s-curve).

Usage Example

{
  "fading": {
    "enabled": true,
    "trackStart": { "duration": 1500, "curve": "s-curve" },
    "seek": { "duration": 500, "curve": "linear" }
  }
}

Overview

By providing a nextTrack in the player update, NodeLink will begin resolving and buffering the subsequent track while the current one is still playing.

When the active track finishes, NodeLink immediately switches to the preloaded resource, resulting in a "gapless" experience.

Usage

{
  "nextTrack": {
    "encoded": "QAAAAAMARFJpY2sgQXN0bGV5...",
    "userData": { "context": "queued" }
  }
}

Overview

The Meaning System allows clients to retrieve encyclopedic information, history, and context for tracks and artists. It aggregates data from multiple providers:

• Wikipedia: Detailed historical and biographical data.
• Letras.mus.br: Track meanings and cultural context (primarily for Portuguese/Spanish content).

This feature is perfect for bots that want to provide "Did you know?" facts about the music being played.

Usage

curl -X GET "http://your-server.com/v4/meaning?encodedTrack=..."

Example Response

{
  "loadType": "meaning",
  "data": {
    "title": "Never Gonna Give You Up",
    "description": "1987 song by Rick Astley",
    "paragraphs": [
      ""Never Gonna Give You Up" is the debut single recorded by English singer-songwriter Rick Astley...",
      "The song was a worldwide number-one hit, initially in the United Kingdom in 1987..."
    ],
    "url": "https://en.wikipedia.org/wiki/Never_Gonna_Give_You_Up",
    "provider": "wikipedia",
    "type": "track"
  }
}

Overview

Eternal Box (based on the Infinite Jukebox algorithm) analyzes a track's rhythm, beats, and acoustic segments to create a graph of similar-sounding points.

During playback, the engine can "jump" from one part of the song to another seamlessly, extending the track indefinitely without sounding repetitive or broken.

How to play

Use the eternalbox: prefix or a supported URL:

• eternalbox:SPOTIFY_ID
• https://eternalboxmirror.xyz/jukebox_go.html?id=SPOTIFY_ID

WebSocket Events

Configuration

// config.js
enableLoadStreamEndpoint: true

Query / Body Parameters

Example Request

curl -X GET "http://your-server.com/v4/loadstream?encodedTrack=QAAAAAMAM0hvdyB0byBBZGQgQ2hhcHRlcnMgdG8gWW91ciBWaWRlb3MgVXNpbmcgVGltZXN0YW1wcwAQWW91VHViZSBDcmVhdG9ycwAAAAAAATSYAAtiMUZvX01fdGo2dwABACtodHRwczovL3d3dy55b3V0dWJlLmNvbS93YXRjaD92PWIxRm9fTV90ajZ3AQA2aHR0cHM6Ly9pLnl0aW1nLmNvbS92aV93ZWJwL2IxRm9fTV90ajZ3L3NkZGVmYXVsdC53ZWJwAAAHeW91dHViZQAAAAAAAAAA&position=30000" \
     -H "Authorization: yourPassword" \
     --output track.pcm

Response

How to use

1. Check for available tracks

When you load a track (especially from YouTube), the response includes an audioTracks array inside pluginInfo. This lists all available audio streams for that video.

To see this information, you must load the track using loadTracks.

"pluginInfo": {
    "audioTracks": [
        {
            "id": "en",
            "name": "English (Original)",
            "isDefault": true,
            "isAutoDubbed": false
        },
        {
            "id": "pt-br",
            "name": "Portuguese (Brazil)",
            "isDefault": false,
            "isAutoDubbed": true
        }
    ]
}

2. Select a track

By default, NodeLink plays the default/original audio. To play a different track (e.g., Portuguese dub), pass the audioTrackId in the track object when updating the player.

curl -X PATCH "http://your-server.com/v4/sessions/{sessionId}/players/{guildId}" \
     -H "Authorization: yourPassword" \
     -H "Content-Type: application/json" \
     -d '{
       "track": {
         "encoded": "...",
         "audioTrackId": "pt-br"
       }
     }'

Use Cases

• Multi-language Videos: Allow users to switch between original audio and dubbed versions.
• Descriptive Audio: Select audio tracks with descriptive commentary for accessibility.

Body

Example Request

curl -X PATCH "http://your-server.com/v4/youtube/config" \
     -H "Authorization: yourPassword" \
     -H "Content-Type: application/json" \
     -d '{
       "refreshToken": "1//0gN...",
       "visitorData": "Cgt..."
     }'

Response

Query Parameters

Response

Methods Supported

Body (POST)

Query Parameters (GET)

Example Request (POST)

curl -X POST "http://your-server.com/v4/youtube/oauth" \
     -H "Authorization: yourPassword" \
     -H "Content-Type: application/json" \
     -d '{"refreshToken": "..."}'

Example Request (GET)

curl -X GET "http://your-server.com/v4/youtube/oauth?refreshToken=..." \
     -H "Authorization: yourPassword"

Response