POST /api/lambda/progress
Checks the rendering progress of a video job initiated via the /api/lambda/render endpoint. This endpoint should be polled periodically until the render is complete.
Request Body
The S3 bucket name returned from the /api/lambda/render endpoint
The render ID (renderId) returned from the /api/lambda/render endpoint
Response
The response varies based on the current state of the render job. Three possible response types:
Progress Response
Returned while the render is in progress.
Indicates the render is still in progress
A number between 0.03 and 1.0 representing the render progress percentage (e.g., 0.5 = 50% complete). Minimum value is 0.03 to indicate the job has started.
Done Response
Returned when the render has completed successfully.
Indicates the render has completed
The public URL to download the rendered video file
The size of the rendered video file in bytes
Error Response
Returned when the render has failed.
Indicates the render encountered a fatal error
Error message describing what went wrong
Example Request
curl -X POST https://your-domain.com/api/lambda/progress \
-H "Content-Type: application/json" \
-d '{
"bucketName": "remotionlambda-useast1-abcdefgh",
"id": "8h3k9d2f-1a2b-3c4d-5e6f-7g8h9i0j1k2l"
}'
// Poll for progress
const checkProgress = async (renderId, bucketName) => {
const response = await fetch('/api/lambda/progress', {
method: 'POST',
headers: {
'Content-Type': 'application/json',
},
body: JSON.stringify({
id: renderId,
bucketName: bucketName
})
});
return await response.json();
};
// Usage with polling
const pollRenderProgress = async (renderId, bucketName) => {
const poll = async () => {
const result = await checkProgress(renderId, bucketName);
if (result.type === 'progress') {
console.log(`Progress: ${(result.progress * 100).toFixed(1)}%`);
// Poll again in 2 seconds
setTimeout(poll, 2000);
} else if (result.type === 'done') {
console.log('Render complete!');
console.log('Video URL:', result.url);
console.log('File size:', result.size, 'bytes');
} else if (result.type === 'error') {
console.error('Render failed:', result.message);
}
};
poll();
};
// Start polling after initiating render
const renderResponse = await fetch('/api/lambda/render', { /* ... */ });
const { renderId, bucketName } = await renderResponse.json();
pollRenderProgress(renderId, bucketName);
Example Responses
In Progress
{
"type": "progress",
"progress": 0.42
}
{
"type": "done",
"url": "https://remotionlambda-useast1-abcdefgh.s3.amazonaws.com/renders/8h3k9d2f/video.mp4",
"size": 2847392
}
{
"type": "error",
"message": "Composition not found: DynamicComp"
}
Polling Best Practices
- Poll every 2-5 seconds to balance responsiveness with API rate limits
- Stop polling once you receive a
done or error response
- Implement a maximum timeout (e.g., 5 minutes) to handle stuck renders
- Display the progress percentage to users for better UX
Implementation Details
The endpoint uses Remotion Lambda’s getRenderProgress() function with the following configuration:
- Function Name: Auto-speculated based on RAM, DISK, and TIMEOUT settings from
config.mjs
- Region: Uses the region configured in
config.mjs (default: us-east-1)