scripts/sync: add --verbose flag and support syncing multiple machines

scripts/sync

@@ -2,33 +2,52 @@
 #!nix-shell -i bash -p bash -p rsync -p sane-scripts.sync-music
 
 usage() {
-  echo "sync all|desko|lappy|moby [passthrough flags ...]"
+  echo "sync [flags ...] <host> [<host> ...] [passthrough flags ...]"
+  echo "where:"
+  echo "  host: all|desko|lappy|moby"
   exit 1
 }
 
+debug() {
+  if [ -n "$SYNC_DEBUG" ]; then
+    echo "$@"
+  fi
+}
+
+ifExists() {
+  local path="$1"
+  shift
+  local cmd="$@"
+  if test -d "$path"; then
+    debug "${cmd[@]}"
+    ${cmd[@]}
+  else
+    debug "skipping action because $path doesn't exist"
+  fi
+}
+
 syncHost() {
   local host=$1
   shift
   local syncFlags=("$@")
   case "$host" in
-    (all)
-      syncHost desko "${syncFlags[@]}"
-      syncHost lappy "${syncFlags[@]}"
-      syncHost moby "${syncFlags[@]}"
-      ;;
     (desko)
-      test -d /mnt/servo/media/Music/Various.Artists && sane-sync-music --compat /mnt/servo/media/Music /mnt/desko/home/Music "${syncFlags[@]}"
+      ifExists /mnt/servo/media/Music/Various.Artists \
+        sane-sync-music --compat /mnt/servo/media/Music /mnt/desko/home/Music "${syncFlags[@]}"
       ;;
     (lappy)
-      test -d /mnt/servo/media/Music/Various.Artists && sane-sync-music --compress --compat /mnt/servo/media/Music /mnt/lappy/home/Music "${syncFlags[@]}"
+      ifExists /mnt/servo/media/Music/Various.Artists \
+        sane-sync-music --compress --compat /mnt/servo/media/Music /mnt/lappy/home/Music "${syncFlags[@]}"
       ;;
     (moby)
       # copy photos/screenshots from moby to desko:
       rsync -arv --exclude servo-macros /mnt/moby/home/Pictures/ /mnt/desko/home/Pictures/from/moby/
       # copy books from servo to moby; delete old/untracked ones, but keep KOreader state files (sdr)
-      test -d /mnt/servo/media/Books/Books && rsync -arv --delete --exclude '*.sdr' /mnt/servo/media/Books/ /mnt/moby/home/Books/local/servo/
+      ifExists /mnt/servo/media/Books/Books \
+        rsync -arv --delete --exclude '*.sdr' /mnt/servo/media/Books/ /mnt/moby/home/Books/local/servo/
       # copy music
-      test -d /mnt/servo/media/Music/Various.Artists && sane-sync-music --compat /mnt/servo/media/Music /mnt/moby/home/Music "${syncFlags[@]}"
+      ifExists /mnt/servo/media/Music/Various.Artists \
+        sane-sync-music --compat /mnt/servo/media/Music /mnt/moby/home/Music "${syncFlags[@]}"
       ;;
     (*)
       usage
@@ -36,4 +55,43 @@ syncHost() {
   esac
 }
 
-syncHost "$@"
+hosts=()
+passthruArgs=()
+parseArgs() {
+  while [[ $# -ge 1 ]]; do
+    local arg=$1
+    case $arg in
+      (desko|lappy|moby)
+        hosts+=("$arg")
+        shift
+        ;;
+      (all)
+        hosts+=(desko lappy moby)
+        shift
+        ;;
+      (--verbose)
+        if [[ "${#hosts[@]}" -eq 0 ]]; then
+          SYNC_DEBUG=1
+          shift
+        else
+          # it's a passthru flag
+          break
+        fi
+        ;;
+      (--help)
+        usage
+        shift
+        ;;
+      (*)
+        break
+        ;;
+    esac
+  done
+  passthruArgs+=("$@")
+}
+
+parseArgs "$@"
+debug "hosts:" "${hosts[@]}"
+for host in "${hosts[@]}"; do
+  syncHost "$host" "${passthruArgs[@]}"
+done