Implement custom posix permissions for pack and packArchive

[norru]

Hello,

our current deployment policy dictates that:

• the application executable must be in the root of the archive rather than in the /bin directory
• none of the unpacked files must be world readable at any time (so they need to be stored in the tarball as 0xx0)
• some of the unpacked files need custom permissions

It is not feasible to change these constraints in the short term.

As a general purpose solution, I would suggest to add some sort of mapping/callback to the create(.*)entry methods so that a filter can be injected as a setting.

Something like this:

  private def createTarEntry(file: File, fileName: String, binDir: File, 
    perms: (File) => Option[Int]) = {
    val archiveEntry = new TarArchiveEntry(file, fileName)
    perms(file) foreach { mode => archiveEntry.setMode(mode) }
    archiveEntry
  }

I have worked this around for the pack task by scanning the target/pack directory tree and changing the permissions on the file system. Unfortunately the packArchive task ignores the filesystem settings.

At the moment I'm not able to fork/pull request.

Regards
Nico

[norru]

Scrap that. I did manage something that can be worked into a fix

#90