-t inst cross-distro GUI installer

State: planning

fpm already has the sh target for raw cross-distro packages. Other attempts had been made at GUI installers (notably Autopackage [defunct] or EPM [semi-active]). It's evident that a shell/scripting-based installer would be most portable/universal though.

Rationale

Thus the inst package is planned to be Shell+Python based initially.

• The envelope format probably ought to be ZIP.
  • Allows the main Python payload to handle extraction easily - just an __init__.py necessary.
  • The pre-stub can just be a few lines then.
  • Alternatively and later a __init__.pl could be added, and a __init__.sh handler fallback in any case.
• As GUI any installable toolkit may be selected (TKinter, Gtk, Qt), at least from the main Python payload.
  • The shell fallback may use xdialog/zenity or just xmessage.
  • The "GUI" may be as lean as just presenting package infos, a package selector, and presenting the installation just per xterm/rxvt/etc.
• The ZIP thus is just a container, may bundle multiple concrete packages; for different architectures even.
• Embedded bundles ought to be DEB packages.
  • Debian packages are by all accounts the most widely used system format; should thus be the preferred/primary actual packaging method.
    • (The LSB doctrine of baseline RPMs being the standard kind of flies in the face of reality.)
    • the Debian/Ubuntu family of distros are the most widely used ones.
  • DEBs are supported by alternative tools, and different platforms already:
    • OpenWRT uses opkg/ipkg a .deb compatible format.
    • Mac OS X has fink to handle .debs.
    • Windows even has wpkg.exe with semi-compatible .deb support.
  • And as fallback for other distros there are extremely obvious options:
    • Using alien for implicit converison and installation.
    • Download or bundle a minimal fpm to convert deb to rpm.
  • Else just can be extracted raw using an unzip | ar | tar pipe. (Invoking post-install scripts is more work then, of course.)

Format idea

A inst bundle would simply be a collection of:

pkgname-1.0.inst (pyzip)
 → __init__.sh
 → __init__.py
 → pkgname_1.0_x86.deb
 → pkgname_1.0_amd64.deb
 → libraryxy_3.7.0_all.deb

So an outer ZIP layer, and DEB packages and distinct installer scripts/fallbacks within.

Notes

Selecting the right archictecture packages is the trivial part; and extracting _all always just as obvious.

The concrete installation process will regularily just chain the whole process to gdebi or dpkg -i or alien -i, otherwise use a two-liner for ar→tar extraction, and lastly XDG/PK register all files.

Most work is likely just exception-probing for and implementing GUIs on Tkinter / Gtk / Qt in the Python payload.

As for the fpm plugin, it can just collect ready-made debs, zip them with payloads. (Or trivially preinvoke the -t deb handler itself for plain file input.)

Research

See Research on prior cross-distro installers. In particular SuperDebs/RUNZ looked sensible (just wasn't cross-distro). Listaller might be worth investigating further for implementation details/reuse.