Replace mode='append'-direct-to-live approach with a safer staging
workflow: Part 2 writes the new sorted layer to temp staging directories,
the user verifies, then a separate copy step adds the files to the live
datasets. Live datasets are never touched until the copy step, and the
copy only adds files — nothing is deleted or overwritten.
- sort_and_write gains out_by_subreddit/out_by_author params (replaces
mode param) so Part 2 can target staging paths
- comments_part2.py, submissions_part2.py: expose new params via Fire
- add_months.sh: rewritten with explicit staging dirs, verify checkpoint,
and find-based copy step
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
Add add_months.sh and merge_layers.sh implementing a layered append
strategy for incremental dataset updates. Each incremental run appends
new sorted partition files alongside existing ones rather than re-sorting
the full corpus, which is prohibitively slow at this dataset scale.
- dumps_helper.py: sort_and_write gains indir/mode params; new
merge_layers function collapses accumulated layers via atomic rename
- comments_part2.py, submissions_part2.py: expose --indir/--mode via Fire
- add_months.sh: new layered append script (not yet tested)
- merge_layers.sh: new layer collapse script (not yet tested)
- comments_merge.py, submissions_merge.py: Spark entry points for merge
- add_new_month.sh: deleted (full re-sort each add is redundant with
build_from_scratch at corpus scale)
- README.md: document three workflows; flag untested sections
Co-Authored-By: Claude Sonnet 4.6 <noreply@anthropic.com>
