Question

Using Ruby (1.9.3) I need to replace a single file in a zip archive.

The situation is as follows. I have ~1000 zip archives that need to be updated, specifically one file in each of them needs to be replaced. The archives are all of the same structure. Is there a quick and dirty way for Ruby, or a library/gem for Ruby, to simply say “replace the file in this zip archive with this file on the filesystem”?

I’ll work on a solution of my own in the meantime.

Answer 1

You can use the zip command, called from the ruby, which probably will be the best solution. From the zip manpage zip manpage

       -d
   --delete
          Remove (delete) entries from a zip archive.  For example:

                 zip -d foo foo/tom/junk foo/harry/\* \*.o

          will remove the entry foo/tom/junk, all of the files that start with foo/harry/, and all of the files that end with .o (in any path).  Note that  shell  path‐
          name expansion has been inhibited with backslashes, so that zip can see the asterisks, enabling zip to match on the contents of the zip archive instead of the
          contents of the current directory.  (The backslashes are not used on MSDOS-based platforms.)  Can also use quotes to escape the asterisks as in

                 zip -d foo foo/tom/junk "foo/harry/*" "*.o"

          Not escaping the asterisks on a system where the shell expands wildcards could result in the asterisks being converted to a  list  of  files  in  the  current
          directory and that list used to delete entries from the archive.

          Under  MSDOS,  -d  is  case sensitive when it matches names in the zip archive.  This requires that file names be entered in upper case if they were zipped by
          PKZIP on an MSDOS system.  (We considered making this case insensitive on systems where paths were case insensitive, but it is possible the archive came  from
          a  system  where case does matter and the archive could include both Bar and bar as separate files in the archive.)  But see the new option -ic to ignore case
          in the archive.

If you want a pure ruby solution take a look at ZipFileSystem