Background
Some submission are runnable. When a user submits a runnable submission to a queue, the queue's Submission Application would check and start the runnable process. This process could take a long time. We want to provide users the ability to stop their running process at anytime that it is running.
Service Layer
Add a new boolean field to submission status called 'cancelRequested'.
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Add a leaderboard widget, including an executionStatus column. The query should use 'where userId==@CURRENT_USER' to show just the submitter's jobs.
Choose the 'stop button' renderer for this column.
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