lib/aur-fetch--mirror

   1 #!/bin/bash
   2 set -o errexit
   3 [[ -v AUR_DEBUG ]] && set -o xtrace
   4 #argv0=fetch--mirror
   5 XDG_CACHE_HOME=${XDG_CACHE_HOME:-$HOME/.cache}
   6 AUR_MIRROR=${AUR_MIRROR:-https://github.com/archlinux/aur}
   7 AUR_MIRROR_TTL=${AUR_MIRROR_TTL:-300}
   8 AUR_MIRROR_BRANCH=${AUR_MIRROR_BRANCH:-main}
   9 AUR_ROOT=${AUR_ROOT:-$XDG_CACHE_HOME/aur}
  10 startdir=$PWD
  11 local_clones=0
  12
  13 # Avoid CDPATH screwing with cd (#1047)
  14 unset -v CDPATH
  15
  16 if [[ $1 = '--lclone' ]]; then
  17     local_clones=1
  18     shift
  19 fi
  20 mkdir -p -- "$AUR_ROOT"
  21
  22 # --------------------------------------------------
  23 # Step 1. Create a sparse checkout of the AUR mirror
  24 git_active_remotes() {
  25     git config --get-all remote.origin.fetch | awk -F'[/:]' '{print $3}'
  26 }
  27
  28 # XXX: this includes refs/heads (which we do not use) but unlike
  29 # git-config this accepts multiple arguments in one call
  30 git_set_branches() {
  31     git remote set-branches origin --add "$AUR_MIRROR_BRANCH" # ensure at least 1 remote
  32     sort -u | xargs -d '\n' git remote set-branches origin
  33 }
  34
  35 git_ls_remote_ttl() {
  36     local cachetime now ttl=$AUR_MIRROR_TTL
  37     printf -v now '%(%s)T' -1
  38
  39     if ! cachetime=$(stat -c %Y "$1" 2>/dev/null) || (( now > (cachetime + ttl) )); then
  40         git ls-remote origin 'refs/heads/*' | awk -F/ '{print $3}' >"$1"
  41     fi
  42 }
  43
  44 exec {fd}< "$AUR_ROOT"
  45 { flock --wait 5 "$fd" || exit 1
  46   cd -- "$AUR_ROOT"
  47
  48   # Shallow clone
  49   if [[ ! $(git rev-parse --is-inside-git-dir 2>/dev/null) ]]; then
  50       git init --bare --initial-branch="$AUR_MIRROR_BRANCH"
  51       git remote add origin "$AUR_MIRROR"
  52   fi
  53
  54   # Keep a refcache to filter out packages which are not in AUR. This is
  55   # includes unlisted packages (unlike `aur pkglist --pkgbase`)
  56   git_ls_remote_ttl 'remote-pkgbase'
  57
  58   # Retrieve list of active remotes
  59   mapfile -t active_remotes < <(git_active_remotes | grep -v "$AUR_MIRROR_BRANCH")
  60
  61   # Only consider AUR targets
  62   mapfile -t target_remotes < <(printf '%s\n' "$@" | grep -Fxf 'remote-pkgbase')
  63
  64   # Set remote branches as union of active remotes and arguments. If '*' is set
  65   # instead, `git fetch origin` in $AUR_ROOT will pull in the entire history.
  66   printf '%s\n' "${target_remotes[@]}" "${active_remotes[@]}" | git_set_branches
  67
  68   # Retrieve objects
  69   if (( ${#target_remotes[@]} )); then
  70       git fetch origin "${target_remotes[@]}"
  71   fi
  72
  73   # Resetting branches is only needed when .git/config contains both refs/heads
  74   # and refs/remotes/origin, i.e. when using git-clone. `--lclone` uses git-init
  75   # and refspec manipulation instead.
  76   # for b in "${target_remotes[@]}"; do
  77   #     git branch --force "$b" origin/"$b"
  78   # done
  79 } >&2
  80
  81 # ------------------------------------------------------------
  82 # Step 2. Propagate each branch in the mirror to a local clone
  83 (( ! local_clones )) && exit
  84 results=()
  85
  86 git_srcdest_origin() {
  87     local refspec=refs/remotes/origin/$1
  88
  89     git config remote.origin.fetch "+$refspec:$refspec"
  90     git fetch --quiet
  91     git checkout --quiet -B master "$refspec"
  92 }
  93
  94 for b in "${target_remotes[@]}"; do
  95     cd -- "$startdir"
  96
  97     # XXX: "Cloning into an existing directory is only allowed if the
  98     # directory is empty"
  99     if [[ ! -d $b/.git ]] && mkdir -- "$b"; then
 100         cd -- "$b"
 101         git init --quiet
 102         git remote add origin "$AUR_ROOT"
 103
 104         # Compared to git clone --local, using $refspec as both source and
 105         # destination allows updates from `git-fetch` in $AUR_ROOT to be
 106         # directly visible in local clones.  $AUR_ROOT does not require
 107         # local branches or refs/heads for this to work.
 108         git_srcdest_origin "$b"
 109
 110         # Export results to aur-fetch
 111         head=$(git rev-parse --verify --quiet HEAD)
 112         results+=("$b:$head")
 113     fi >&2
 114 done
 115
 116 # The lock is only released here, because we do not want an instance to modify
 117 # AUR_ROOT while local git-clones are still underway. Additionally, local clones
 118 # use cp(1) and are thus a cheap operation. See --local in git-clone(1).
 119 exec {fd}<&-
 120
 121 if (( ${#results[@]} )); then
 122     printf '%s\n' "${results[@]}"
 123 fi