Extra Empty metadata

[rgaudin]

ZIMs made with zimwriterfs-like zimscraperlib.zim.filesystem:make_zim_file() appear to set non-set metadata to an empty string instead of not setting said metadata.

See:

• http://library.kiwix.org/raw/bayardcuisine_fr/meta/Source
• http://library.kiwix.org/raw/bayardcuisine_fr/meta/Flavour
• http://library.kiwix.org/raw/mesptitesquestions_fr/meta/Source

It seems zimwriterfs 2.0.1-1 was doing the same:

• http://library.kiwix.org/raw/gutenberg_ale_all/meta/Flavour
• http://library.kiwix.org/raw/gutenberg_ale_all/meta/Source But zimwriterfs 3.1.0 is not affected:
• http://library.kiwix.org/raw/eleda_fr/meta/Source

[rgaudin]

See #95

[kelson42]

Clearly bugs IMO

[rgaudin]

Fixed in 3.0.0