git-push-as-remote

   1 #!/bin/sh
   2
   3 # Registers the current state of this repository in a remote repository under a special ID (a specially named remote which should be well-known as the refernce to this working copy/repository).
   4 #
   5 # Author: Ivan Zakharyaschev imz at altlinux dot org, March 2009, May 2010.
   6 # I publish it under GPLv2 or later.
   7 # (GPLv2 is chosen to match the license of the base tool, Git.)
   8 #
   9 # Doing so is useful for keeping track of the states of all your working copies.
  10
  11 # In a sense, there is almost NO SENSE in this command: one can type the corresponding (not so complex) refspec by hand,
  12 # or set up the remote appropriately (see the comment at the end of file). Also, the alternatives allow more flexibility
  13 # in how you name and store things remotely.
  14
  15 # The special ID for this repository should be set by
  16 # "git config [ --global | ... ] shortcut-scripts.as-remote <newval>".
  17 #
  18 # For example, I use IDs corresponding to my working computers, e.g., @dell, @vaio, etc.
  19 #
  20 # In a sense, the action of this script is just the reverse of the action that would be done by some "git push" from a remote to this repository at the end: it would sync the state of this repository with remote-refs there (with a special ID--the remote name corresponding to this repository). This script does the same, but it is called from the other side.
  21 #
  22 # It's useful because it's not always possible (a server) or desirable (a portable disk) to set up a the corresponding repository at the other end, but you may wish to keep track of the states of your various working sites (repositories) for this project.
  23 #
  24 # Usage: passes all args to "git push", and adds its special refspec.
  25 #
  26 # This script together with the shortcut-scripts.as-remote parameter was made by me just to save typing/thinking over the special refspec.
  27
  28 set -e
  29
  30 usage() {
  31     echo $"git push-as-remote ... , where ... are the args for \"git push\"."
  32     echo $"This script does its best to detect the default case and to push to 'origin' then; but you might need to specify a remote explicitly."
  33     echo $"You must have set \"git config shortcut-scripts.as-remote\" (possibly globally)."
  34     echo $"This script will create on the remote side branches refs/remotes/AS_REMOTE/* tracking the state of this repo."
  35 }
  36
  37 # Try to skip all options and see whether there is a non-option arg (which must be a remote).
  38 # Not perfect: if an option has a parameter, and they are given without an equal sign in between,
  39 # this will fool my code: it is'll be considered an argument (a remote).
  40 # Well, then one will simply get an error message from "git push".
  41 # That's because I can't parse "git push"'s options perfectly without a formal specification of the options,
  42 # and I don't want to write up one by hand.
  43 #
  44 # (FR: git commands should print out the specification of options in the format accepted by "git rev-parse --parseopt",
  45 # then one could more easily implement extensions to the git commands, like this one.)
  46 readonly -a VERBATIM_ARGS=("$@")
  47 while (( $# > 0 )); do
  48     case "$1" in
  49         -h|--help|--usage)
  50             usage
  51             exit 0
  52             ;; # never reached actually
  53         -*)
  54             shift
  55             continue
  56             ;; # never reached actually
  57         *)
  58             break
  59             ;; # never reached actually
  60     esac
  61 done
  62 if (( $# == 0 )); then
  63     # A refspec can only be given in the command line for "push" after an explicitly specified remote,
  64     # so since we pass our special refspec, we must pass a certain remote as well.
  65     # If there are no args given (except for the options), then there is definitely no remote specified,
  66     # so we emulate the "git push"'s default behavior (per manpage):
  67     # "<remote> is the current branch's remote (or origin, if no remote is configured for the current branch)".
  68     # Our refspec is "global", not related to the current branch, but spanning all the branches,
  69     # so the only reasonable emulation is using "origin".
  70     readonly -a args=("${VERBATIM_ARGS[@]}" origin)
  71 else
  72     readonly -a args=("${VERBATIM_ARGS[@]}")
  73 fi
  74
  75 readonly AS_REMOTE="$(git config shortcut-scripts.as-remote)"
  76 if [[ ! "$AS_REMOTE" ]]; then
  77     usage
  78     exit 1
  79 fi
  80
  81 # It should do even "non-clean" ref updates (non-ff), because it's like a _mirroring_ tool.
  82 git push "${args[@]}" "+refs/heads/*:refs/remotes/$AS_REMOTE/*"
  83
  84 # Alternatively to using this command and in order to save even more typing, you could set up the refspecs in the config, like this:
  85 #
  86 # [remote "origin"]
  87 #       url = /mnt/usbmem1/my/code/git-shortcuts/.git
  88 #       fetch = +refs/heads/*:refs/remotes/origin/*
  89 #       push = refs/heads/*:refs/heads/*
  90 #       push = +refs/heads/*:refs/remotes/@vaio/*
  91 #
  92 # This way you even don't loose the default possibly convenient behavior of "git push" (push only branches already present remotely):
  93 # there is a special simple refspec for this behavior -- ":" (per manpage):
  94 #
  95 #            The special refspec : (or {plus}: to allow non-fast forward updates) directs git to push "matching"
  96 #            branches: for every branch that exists on the local side, the remote side is updated if a branch of
  97 #            the same name already exists on the remote side. This is the default operation mode if no explicit
  98 #            refspec is found (that is neither on the command line nor in any Push line of the corresponding
  99 #            remotes file---see below).
 100 #
 101 # Warning: multiple "push = " lines seem not to work in git-1.5.5.5-alt1, should try putting it to .git/remotes/... .