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Once the transcripts for a video have been successfully migrated, all of the changes made to S3 are permanent. As the transcripts have been made available to the end users, it must be ensured that a subsequent run of the script does not overwrite the S3 data. Each course migration event will be logged via the PersistOnFailureTask mixin. The script will be idempotent so it can be re-run even if it ran before and failed midway(after) a failed previous run.
Implementation
A Django management script will be written that will traverse the contentstore and for each course will find all the video objects. Any transcripts related to the found video objects will be pushed to S3 as an atomic task. In the transaction, a video's transcripts metadata will be migrated from video component to edxval and the corresponding transcript content will be migrated from contentstore to S3.
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