Upload, Cache and Retries
Player devices go offline. CamGrabber is built so that no photo capture is lost.
Upload queue
Photo captures are uploaded through a queue. Each attempt is limited by the upload timeout (see Capture and upload settings); a timed-out attempt counts as failed and the photo capture returns to the queue.
Retry with growing intervals
After a failed upload CamGrabber retries with a randomized, growing delay, so that grabbers spread their retries over time. The first successful upload returns the grabber to normal operation.
Offline cache
A photo capture that cannot be uploaded is stored on disk and waits for connectivity:
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The cache uses a limited share of the free disk space.
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When the cache overflows, the oldest photo captures are deleted first.
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The cache is persistent: it survives CamGrabber restarts and device reboots. Pending photo captures resume uploading when the application starts.
Combined with capture-time stamping, this means a player can spend hours offline and still deliver a complete, correctly dated photo report afterwards.