> ## Documentation Index
> Fetch the complete documentation index at: https://committ.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# useFreshPhotoUrl

> Generates time-limited signed URLs for verification photo uploads to Convex Storage.

# useFreshPhotoUrl

**Source:** `hooks/useFreshPhotoUrl.ts` (86 lines)

The useFreshPhotoUrl hook handles the complete photo upload lifecycle for embarrassing photo penalties, generating time-limited signed URLs and uploading the captured image to Convex Storage.

***

## Upload Pipeline

```
Camera Capture (local file URI)
    │
    ├── 1. Request signed upload URL from Convex
    │       → convex.mutation(api.storage.generateUploadUrl)
    │
    ├── 2. Upload photo file to Convex Storage
    │       → fetch(signedUrl, { method: "POST", body: blob })
    │
    ├── 3. Receive Storage ID
    │       → storageId = response.storageId
    │
    └── 4. Embed Storage ID in penalty config
            → penalty.config.photoStorageId = storageId
```

***

## Time-Limited URLs

The signed upload URL is valid for a short window (typically 60 seconds). This prevents replay attacks where a captured URL could be reused to upload arbitrary content at a later time.

***

## Blob Conversion

The hook converts the local file URI (from the camera or gallery) into a Blob for upload:

```typescript theme={null}
const response = await fetch(localFileUri);
const blob = await response.blob();
```

***

## Integration with useCommitTask

The useFreshPhotoUrl hook is called by useCommitTask before the Triple-Write executes. The returned storage ID is embedded in the penalty config, which is then frozen onto each generated task instance as part of the immutable penalty snapshot.

***

## Error Handling

If the upload fails (network error, storage quota exceeded), the hook returns null for the storage ID. The useCommitTask hook checks for this and aborts the commit with a user-facing error message rather than creating a commitment with a broken penalty reference.