Lyrics Generation Callbacks

When you submit a lyrics generation task to the Suno API, you can use the callBackUrl parameter to set a callback URL. The system will automatically push the results to your specified address when the task is completed.

Callback Mechanism Overview

The callback mechanism eliminates the need to poll the API for task status. The system will proactively push task completion results to your server.

Callback Timing

The system will send callback notifications in the following situations:

Lyrics generation task completed successfully
Lyrics generation task failed
Errors occurred during task processing

Callback Method

HTTP Method: POST
Content Type: application/json
Timeout Setting: 15 seconds

Callback Request Format

When the task is completed, the system will send a POST request to your callBackUrl in the following format:

{
  "code": 200,
  "msg": "All generated successfully.",
  "data": {
    "callbackType": "complete",
    "task_id": "3b66882fde0a5d398bd269cab6d9542b",
    "data": [
      {
        "error_message": "",
        "status": "complete",
        "text": "[Verse]\nMoonlight spreads across the windowsill\nStars dance, never standing still\nNight breeze weaves dreams with gentle skill\nLeaving all worries on the hill\n\n[Verse 2]\nLights reflect in your bright eyes\nLike meteors across the skies\nThe world stops in that moment's prize\nChasing future, no goodbyes\n\n[Chorus]\nIn starry dreams we find tomorrow\nBreak free from ordinary sorrow\nAll our dreams will bloom and follow\nDon't fear the path, don't fear tomorrow",
        "title": "Starry Night Dreams"
      }
    ]
  }
}

Status Code Description

code

integer

required

Callback status code indicating task processing result:

Status Code	Description
200	Success - Request has been processed successfully
400	Please try rephrasing with more specific details or using a different approach
500	Internal Error - Please try again later

msg

string

required

Status message providing detailed status description

data.callbackType

string

required

Callback type, fixed as complete

data.task_id

string

required

Task ID, consistent with the task_id returned when you submitted the task

data.data

array

required

Generated lyrics list

data.data[].text

string

Lyrics content, returns complete lyrics text on success

data.data[].title

string

Lyrics title

data.data[].status

string

required

Generation status:

complete - Generation successful
failed - Generation failed

data.data[].error_message

string

Error message, valid when status is failed

Callback Reception Examples

Here are example codes for receiving callbacks in popular programming languages:

Node.js
Python
PHP

const express = require('express');
const app = express();

app.use(express.json());

app.post('/suno-lyrics-callback', (req, res) => {
  const { code, msg, data } = req.body;
  
  console.log('Received lyrics callback:', {
    taskId: data.task_id,
    status: code,
    message: msg,
    callbackType: data.callbackType
  });
  
  if (code === 200) {
    // Task completed successfully
    console.log('Lyrics generation completed:', data.data);
    
    // Process generated lyrics data
    data.data.forEach(lyrics => {
      if (lyrics.status === 'complete') {
        console.log(`Lyrics title: ${lyrics.title}`);
        console.log(`Lyrics content: ${lyrics.text}`);
      } else if (lyrics.status === 'failed') {
        console.log(`Lyrics generation failed: ${lyrics.error_message}`);
      }
    });
    
  } else {
    // Task failed
    console.log('Task failed:', msg);
    
    // Handle failure cases...
  }
  
  // Return 200 status code to confirm callback received
  res.status(200).json({ status: 'received' });
});

app.listen(3000, () => {
  console.log('Callback server running on port 3000');
});

from flask import Flask, request, jsonify
import json

app = Flask(__name__)

@app.route('/suno-lyrics-callback', methods=['POST'])
def handle_callback():
    data = request.json
    
    code = data.get('code')
    msg = data.get('msg')
    callback_data = data.get('data', {})
    task_id = callback_data.get('task_id')
    callback_type = callback_data.get('callbackType')
    
    print(f"Received lyrics callback: {task_id}, status: {code}, type: {callback_type}, message: {msg}")
    
    if code == 200:
        # Task completed successfully
        lyrics_list = callback_data.get('data', [])
        print(f"Lyrics generation completed, generated {len(lyrics_list)} lyrics")
        
        for lyrics in lyrics_list:
            if lyrics['status'] == 'complete':
                print(f"Lyrics title: {lyrics['title']}")
                print(f"Lyrics content: {lyrics['text']}")
            elif lyrics['status'] == 'failed':
                print(f"Lyrics generation failed: {lyrics['error_message']}")
                
    else:
        # Task failed
        print(f"Task failed: {msg}")
        
        # Handle failure cases...
    
    # Return 200 status code to confirm callback received
    return jsonify({'status': 'received'}), 200

if __name__ == '__main__':
    app.run(host='0.0.0.0', port=3000)

<?php
header('Content-Type: application/json');

// Get POST data
$input = file_get_contents('php://input');
$data = json_decode($input, true);

$code = $data['code'] ?? null;
$msg = $data['msg'] ?? '';
$callbackData = $data['data'] ?? [];
$taskId = $callbackData['task_id'] ?? '';
$callbackType = $callbackData['callbackType'] ?? '';

error_log("Received lyrics callback: $taskId, status: $code, type: $callbackType, message: $msg");

if ($code === 200) {
    // Task completed successfully
    $lyricsList = $callbackData['data'] ?? [];
    error_log("Lyrics generation completed, generated " . count($lyricsList) . " lyrics");
    
    foreach ($lyricsList as $lyrics) {
        if ($lyrics['status'] === 'complete') {
            error_log("Lyrics title: " . $lyrics['title']);
            error_log("Lyrics content: " . $lyrics['text']);
        } elseif ($lyrics['status'] === 'failed') {
            error_log("Lyrics generation failed: " . $lyrics['error_message']);
        }
    }
    
} else {
    // Task failed
    error_log("Task failed: $msg");
    
    // Handle failure cases...
}

// Return 200 status code to confirm callback received
http_response_code(200);
echo json_encode(['status' => 'received']);
?>

Best Practices

Callback URL Configuration Recommendations

Use HTTPS: Ensure your callback URL uses HTTPS protocol for secure data transmission
Verify Source: Verify the legitimacy of the request source in callback processing
Idempotent Processing: The same task_id may receive multiple callbacks, ensure processing logic is idempotent
Quick Response: Callback processing should return a 200 status code as quickly as possible to avoid timeout
Asynchronous Processing: Complex business logic should be processed asynchronously to avoid blocking callback response
Status Checking: Check the status field of each lyrics item to distinguish between success and failure cases

Important Reminders

Callback URL must be a publicly accessible address
Server must respond within 15 seconds, otherwise it will be considered a timeout
If 3 consecutive retries fail, the system will stop sending callbacks
Please ensure the stability of callback processing logic to avoid callback failures due to exceptions
Pay attention to handling lyrics generation failure cases, check the error_message field for specific error information

Troubleshooting

If you do not receive callback notifications, please check the following:

Network Connection Issues

Confirm that the callback URL is accessible from the public network
Check firewall settings to ensure inbound requests are not blocked
Verify that domain name resolution is correct

Server Response Issues

Ensure the server returns HTTP 200 status code within 15 seconds
Check server logs for error messages
Verify that the interface path and HTTP method are correct

Content Format Issues

Confirm that the received POST request body is in JSON format
Check that Content-Type is application/json
Verify that JSON parsing is correct

Lyrics Processing Issues

Confirm proper handling of lyrics status field
Check if processing of failed status lyrics is missed
Verify that lyrics content parsing is correct

Alternative Solution

If you cannot use the callback mechanism, you can also use polling:

Poll Query Results

Use the get lyrics details endpoint to regularly query task status. We recommend querying every 30 seconds.

Lyrics Generation

WAV Conversion

Vocal Removal

Music Video Generation

Lyrics Generation Callbacks

Callback Mechanism Overview

Callback Timing

Callback Method

Callback Request Format

Status Code Description

Callback Reception Examples

Best Practices

Callback URL Configuration Recommendations

Important Reminders

Troubleshooting

Alternative Solution

Poll Query Results

Lyrics Generation

WAV Conversion

Vocal Removal

Music Video Generation

​Callback Mechanism Overview

​Callback Timing

​Callback Method

​Callback Request Format

​Status Code Description

​Callback Reception Examples

​Best Practices

​Callback URL Configuration Recommendations

​Important Reminders

​Troubleshooting

​Alternative Solution

Poll Query Results

Callback Mechanism Overview

Callback Timing

Callback Method

Callback Request Format

Status Code Description

Callback Reception Examples

Best Practices

Callback URL Configuration Recommendations

Important Reminders

Troubleshooting

Alternative Solution