[Enhancement] support 7zip archives

[Keith Davies]

calibre has some useful behavior when import certain archive files (ZIP and RAR among them; I haven't checked other formats). Lately I've been storing a fair number of 7zip (.7Z) files. It would be a grand convenience to have similar behavior applied to uploaded 7zip files.

I have a workaround: unpack the 7z, repack as ZIP or RAR, load those instead... but this would be much more convenient to me.

(running calibre v6.26 on Windows 10)

[Kovid Goyal (kovid)]

This is not worth the effort for me personally. If some one else wants to implement it, I will be happy to supply any needed guidance. If so, re-open the ticket and we can discuss it.

[Keith Davies (kjdavies)]

@kovid fair enough. If I knew more python I might take a run at it... but I figured it was worth asking. Thanks for looking at it.

[Kovid Goyal (kovid)]

No harm in asking. Actually given that calibre already includes py7zr
this should not be hard to implement. If you are willing to do the
testing I can add basic support. Attach a couple of sample 7z archves
and I will take a look.

[Keith Davies (kjdavies)]

First sample, 7z file containing single PDF

[Keith Davies (kjdavies)]

Second sample, 7z file containing five PNG files.

[Keith Davies (kjdavies)]

Two 7z files attached, thanks @kovid

[Kovid Goyal (kovid)]

Fixed in branch master. The fix will be in the next release. calibre is usually released every alternate Friday.

[Keith Davies (kjdavies)]

Cool! Thanks @kovid, I'll be sure to take a look as soon as it's out.

[Kovid Goyal (kovid)]

You dont need to wait, https://manual.calibre-ebook.com/develop.html