Only push usage payloads when WebRTC connection was established

[rafel-roboflow]

What does this PR do?

Previously usage payloads were always flushed when the modal function completed, including the case where no WebRTC connection could be established at all. Move the push so it only fires on the success path and on the "connection established but no frames" error path, and skip it entirely when the connection was never established.

Type of Change

• Bug fix (non-breaking change that fixes an issue)

Testing

• I have tested this change locally

Test details:
Running locally

Checklist

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code where necessary, particularly in hard-to-understand areas
• My changes generate no new warnings or errors
• I have updated the documentation accordingly (if applicable)

Additional Context

N/A

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Note

Medium Risk
Adjusts usage-flush behavior in the WebRTC Modal worker, which can affect billing/telemetry accuracy. Change is small and localized but touches usage reporting on error paths.

Overview
Usage tracking in webrtc_worker/modal.py is adjusted so usage_collector.push_usage_payloads() is not called when a WebRTC connection was never established.

Payloads are now flushed only on the normal success path and on the "connection established but no frames processed" failure path, avoiding sending usage for sessions that never connected.

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Cursor Bugbot has reviewed your changes and found 1 potential issue.

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Recorded usage still pushed by background threads

High Severity

record_usage() is still called unconditionally (even when the connection was never established), but only push_usage_payloads() is skipped. The UsageCollector singleton has a background _collector_thread that periodically calls _enqueue_usage_payload() every flush_interval seconds (default 10s), which will enqueue and eventually send the recorded data anyway. Additionally, if the Modal container is reused for a subsequent request, the stale recorded data accumulates in self._usage and gets pushed on the next successful push_usage_payloads() call. Moving record_usage() inside the conditional (or guarding it with connection_established) is needed to actually prevent usage from being reported when no connection was established.

Additional Locations (1)

• inference/core/interfaces/webrtc_worker/modal.py#L470-L475

 

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