denkfabrik-li b44c6bf098 Add a file to a zip once, however many ways the selection reaches it ...

BuildZipDownloadJob walks the loose file ids and then every selected
folder's subtree, and adds whatever each pass finds. A selection can
reach the same file from more than one of them, and nothing noticed:

  file_ids [f], folder_ids [Reports]
    -> ['report.pdf', 'Reports/report.pdf']

  file_ids [f], folder_ids [Reports, Reports/Q1]
    -> three entries, file_count 3, total_size three times the file

Two copies of the same bytes in one archive, and total_size is what the
size cap is checked against, so a selection could also be refused for a
weight it does not have.

The one that costs more than bandwidth is delivery. It logs one
FileDownloaded per contained file, and DownloadAllowance counts those
records -- so a file limited to a single download left in three copies
while the log recorded one. Measured: three entries, one record.

Two causes, so two halves.

`$added` is now keyed by id instead of being appended to a list, and the
folder pass skips a file already in the archive. A lookup rather than a
scan because the selection cap is 10000 sources. The loose pass runs
first, so a file picked both ways sits under its loose name; either
answer is defensible, but it has to be the same one every run.

And a selected folder inside another selected folder is dropped before
either is walked. Zipping both would reach every file in the inner one
twice, and which path the surviving entry ended up under would be decided
by the order the rows came back in. Keeping the outer folder keeps the
fuller path -- Reports/Q1/report.pdf rather than Q1/report.pdf.

Containment is decided on the materialized path, so it is one comparison
per pair with no queries: a folder's path starts with an ancestor's
subtreePathPrefix(), and both end in '/', so /5/ cannot match /50/.

Not changed: the per-file re-checks inside the folder pass. Visibility
and the download allowance are still re-derived per file, and the skip
happens before them, so a duplicate never spends an allowance twice
either. Nor the selection endpoint -- a caller may send whatever
selection they like, and the job is where it is resolved.

Four tests. Three measured red against the unfixed job (3 failed / 32
passed): the loose-plus-folder case, the nested-folder case, and the
three-way case asserted through delivery rather than through the archive.
The fourth -- two selected folders that merely share a name are both
zipped -- is green either way and guards the pruning against being about
names rather than containment.

Full suite passes (2052 passed / 2 skipped), PHPStan level 8 clean.

2026-08-28 01:27:26 +02:00

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BuildZipDownloadJob.php

Add a file to a zip once, however many ways the selection reaches it

2026-08-28 01:27:26 +02:00