[cluster] deploy: add -P option

The -P option allows to transfer the files in parallel rather than one
by one.

cluster/README

@@ -56,5 +56,8 @@ Dependency: parallel-ssh (pssh)
 = cluster-deploy.sh =
 
 Deploy one or more files in parallel on every host of the hosts' list.
+By default, the files are transfered one by one, to be sure to notice
+the errors for each file (bad permissions, out of space, etc.), but the
+-P option allows to transfer them all together.
 
 Dependency: parallel-scp (pscp)

cluster/cluster-deploy.sh

@@ -9,32 +9,43 @@
 # http://sam.zoy.org/wtfpl/COPYING for more details.
 #
 # Deploy files on a number of remote hosts using Parallel SCP.
+
 #set -x
 
 print_usage()
 {
-  echo "Usage: $0 [-l login] <hosts_list> <file1> [file2 [...]]"
+  echo "Usage:"
+  echo "  $0 [-P] [-l login] <hosts_list> <file1> [file2 [...]]"
+  echo "-P: transfer files in parallel instead of one by one."
 }
 
-# Do we have at least a host list and a file?
+# Parse the optional arguments
+while [ $# -gt 2 ] ; do
+  case $1 in
+    "-l")
+      LOGIN="$2"
+      shift
+      shift
+      ;;
+    "-P")
+      PARALLEL=1
+      shift
+      ;;
+    *)
+      break
+      ;;
+  esac
+done
+
+# Do we still have at least a host list and a file?
+# Note: if the program was wrongly called but still has 2 arguments, for
+# example with "cluster-deploy -l root -P my_file", it will try to use
+# "-P" as hosts' list and "my_file" as the file to be transfered.
 if [ $# -lt 2 ] ; then
   print_usage
   exit 1
 fi
 
-# Parse the optional arguments
-if [ "$1" = "-l" ] ; then
-  LOGIN="$2"
-  shift
-  shift
-
-  # Do we still have at least a host list and a file?
-  if [ $# -lt 2 ] ; then
-    print_usage
-    exit 3
-  fi
-fi
-
 # Check dependencies
 PSCP=$(command -v parallel-scp || command -v pscp.pssh || command -v pscp)
 if [ "$PSCP" = "" ] ; then
@@ -53,6 +64,12 @@ if [ "$LOGIN" != "" ] ; then
   LOGIN="-l $LOGIN"
 fi
 
+# Transfer the files in parallel...
+if [ "$PARALLEL" = "1" ] ; then
+  exec $PSCP -r $LOGIN -h "$HOSTS" -- "$@" ~
+fi
+
+# ... or one by one
 for FILE in "$@" ; do
   echo "Deploying '$FILE'..."
   $PSCP -r $LOGIN -h "$HOSTS" -- "$FILE" ~