callBackUrl
parameter to set a callback URL. When the task is completed, the system will automatically push the results to your specified address.
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 yourcallBackUrl
in the following format:
Status Code Description
Callback status code indicating task processing result:
Status Code | Description |
---|---|
200 | Success - Lyrics generation completed |
400 | Bad Request - Parameter error, content violation, etc. |
451 | Download Failed - Unable to download related files |
500 | Server Error - Please try again later |
Status message providing detailed status description
Callback type indicating the current callback stage:
complete
: Lyrics generation completederror
: Task failed
Task ID, consistent with the taskId returned when you submitted the task
Lyrics generation result information, returns multiple lyrics variants on success
Generated lyrics content, including song structure markers (e.g., [Verse], [Chorus], etc.)
Lyrics title
Lyrics generation status:
complete
: Generation completedfailed
: Generation failed
Error message, contains specific error description when status is failed
Callback Reception Examples
Here are example codes for receiving callbacks in popular programming languages: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 taskId 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
- Lyrics Storage: Lyrics content should be saved to database or file system promptly
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 content policy compliance to avoid generation failures due to policy violations
- Lyrics content may contain special characters, pay attention to encoding handling
Troubleshooting
If you do not receive callback notifications, please check the following:Network Connection Issues
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
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
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
Lyrics Processing Issues
- Note that lyrics content may contain line breaks and special characters
- Ensure text encoding is handled correctly (recommend using UTF-8)
- Verify lyrics save paths and permissions
- Note whether lyrics content complies with content policies
Alternative Solution
If you cannot use the callback mechanism, you can also use polling:Poll Query Results
Use the get lyrics generation details endpoint to regularly query task status. We recommend querying every 30 seconds.