External Video Transcripts are the transcripts for the video component that does not have {{edx_video_id}} set. This document specifically proposes transcripts flow for such video components.
In VideoTranscript data model, we have a {{video_id]} which is unique together with {{language_code}}.
Assuming a video component that does not have an {{edx`edx_video_id}}id`
On Fresh Video Component
A transcript is uploaded for a language from video component. There will be a call to VAL and a new UUID will be generated which will serve as video_id in creating the corresponding record in VideoTranscript data model (the content will be uploaded to S3/whatever storage is configured). This UUID will be returned back to Video Component. Video Component will have a new Video xField to contain the returned UUID.
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