Environment `MANGADEXDL_ZIP_COMPRESSION_LEVEL` is not working

[mansuf]

Environment `MANGADEXDL_ZIP_COMPRESSION_LEVEL` is not working

[mansuf]

I forgot to put example usage in the docs how to use compression for cbz and epub formats, sorry about that.

Basically, you need to set 2 environments to enable compression

• MANGADEXDL_ZIP_COMPRESSION_TYPE
• MANGADEXDL_ZIP_COMPRESSION_LEVEL

By default, MANGADEXDL_ZIP_COMPRESSION_TYPE is set to stored which means the archive is not compressed at all. So you need to set it to other than stored (deflated, bzip2, lzma)

set MANGADEXDL_ZIP_COMPRESSION_TYPE=deflated
set MANGADEXDL_ZIP_COMPRESSION_LEVEL=1
mangadex-dl.exe "https://mangadex.org/chapter/9f20eb08-abe9-4fb6-acde-5f85049fe24d" --save-as cbz

As you seen in the docs, if you set MANGADEXDL_ZIP_COMPRESSION_TYPE to lzma, environment MANGADEXDL_ZIP_COMPRESSION_LEVEL has no effect at all.

set MANGADEXDL_ZIP_COMPRESSION_TYPE=lzma
mangadex-dl.exe "https://mangadex.org/chapter/9f20eb08-abe9-4fb6-acde-5f85049fe24d" --save-as cbz

Why is no compression even the default? Deflated level 1 is producing a noticeable difference with jpegs (like 230kb -> 191kb), while higher levels doesn't do much (deflated L9 189kb, other compression type are also similar).
I'd guess that deflated level 1 has negligible impact on compression and decompression speeds, and there are no compatibility issues either, I don't see drawbacks with it.

The reason i did this because some systems may not have required modules to do compression stuff. Maybe you thinking that you have all requirements, but i'm thinking about the other users. Also it saves time for me to debug errors.

[NLZ]

Ah thanks, specifying both MANGADEXDL_ZIP_COMPRESSION_TYPE and MANGADEXDL_ZIP_COMPRESSION_LEVEL indeed works.