pyHanko 0.2.0 alpha

The release has been uploaded to PyPI. Documentation is available on ReadTheDocs.

Note: The public API is not completely stable yet, so future releases may still include API changes. This is particularly likely for the validation code and the pdf_utils package; please refer to the documentation for further details.

Change log

New features and enhancements

Signing

• Allow the caller to specify an output stream when signing.

Validation

• The incremental update analysis functionality has been heavily refactored into something more rule-based and modular. The new difference analysis system is also much more user-configurable, and a (sufficiently motivated) library user could even plug in their own implementation.
• The new validation system treats /Metadata updates more correctly, and fixes a number of other minor stability problems.
• Improved validation logging and status reporting mechanisms.
• Improved seed value constraint enforcement support: this includes added support for /V, /MDP, /LockDocument, /KeyUsage and (passive) support for /AppearanceFilter and /LegalAttestation.

CLI

• You can now specify negative page numbers on the command line to refer to the pages of a document in reverse order.

General PDF API

• Added convenience functions to retrieve references from dictionaries and arrays.
• Tweaked handling of object freeing operations; these now produce PDF null objects instead of (Python) None.

Bugs fixed

• root_ref now consistently returns a Reference object
• Corrected wrong usage of @freeze_time in tests that caused some failures due to certificate expiry issues.
• Fixed a gnarly caching bug in HistoricalResolver that sometimes leaked state from later revisions into older ones.
• Prevented cross-reference stream updates from accidentally being saved with the same settings as their predecessor in the file. This was a problem when updating files generated by other PDF processing software.