use setDeterministicID() from qpdf to produce bit-by-bit identical output without dropping the /ID #400
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Codecov ReportBase: 97.02% // Head: 97.02% // Increases project coverage by
Additional details and impacted files@@ Coverage Diff @@
## master #400 +/- ##
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Coverage 97.02% 97.02%
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Files 46 46
Lines 4234 4237 +3
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+ Hits 4108 4111 +3
Misses 126 126
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…tput without dropping the /ID
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We want to be able to create PDF files that are bit-by-bit identical if they share the same content. By default, the
IDmetadata will always differ because qpdf usesQUtil::get_current_time()as part of the values it hashes. Setting theIDmetadata to a static value is a bad idea because it would not make the file in question uniquely identifiable anymore according to PDF 1.7 reference section 10.3 "File Identifiers".Luckily for us, qpdf offers the
setDeterministicID()function which avoids using the current time and the filename as input for the MD5 hash computation. This pull request exposes this functionality in pikepdf.Fixes: https://gitlab.mister-muffin.de/josch/img2pdf/issues/150