Intelligent argument parsing added and possibility to specify the config file on the command line re-added.

CHANGELOG

@@ -1,3 +1,9 @@
+0.8 (05 August 2012)
+===================
+  * Improved argument parsing. Now the script is insensitive to the order of appearance of the options and handles correctly optional options parameters
+  * Re-added possibility to specify the config file on the command line, which is now th recommanded way to do (facilitating script updates)
+  * Fix "unary operator expected warning" in some rare cases
+
 0.7.1 (9 July 2012)
 ===================
   * Adding 'duplicity-backup.conf' to .gitignore

README

@@ -57,9 +57,16 @@ CONFIGURATION
 
 The configuration takes place in a separate config file and is documented there.
 
-The script looks for its configuration by reading the config file specified in
+The script looks for its configuration by reading the config file specified by
-the CONFIG parameter at the beggining of the script. Be sure to edit it to match
+the command line option -c and fallback on the CONFIG parameter at the beggining
-the actual location of your config file.
+of the script otherwise. 
+
+Be sure to specify it on the command line or to edit the CONFIG parameter in the
+script to match the actual location of your config file.
+
+NOTE: to ease future updates of the script, you may want not to edit the script
+      at all and to specify systematically the path to your config file on the 
+      command line with the -c option.
 
 COMMON USAGE EXAMPLES
 =====================
@@ -68,36 +75,36 @@ COMMON USAGE EXAMPLES
     $ duplicity-backup.sh
 
 * Run an incremental backup:
-    $ duplicity-backup.sh --backup
+    $ duplicity-backup.sh [-c config_file] --backup
 
 * Force a one-off full backup:
-    $ duplicity-backup.sh --full
+    $ duplicity-backup.sh [-c config_file] --full
 
 * Restore your entire backup:
-    $ duplicity-backup.sh --restore
+    $ duplicity-backup.sh [-c config_file] --restore
     You will be prompted for a restore directory
 
-    $ duplicity-backup.sh --restore /home/user/restore-folder
+    $ duplicity-backup.sh [-c config_file] --restore /home/user/restore-folder
     You can also provide a restore folder on the command line.
 
 * Restore a specific file in the backup:
-    $ duplicity-backup.sh --restore-file
+    $ duplicity-backup.sh [-c config_file] --restore-file
     You will be prompted for a file to restore to the current directory
 
-    $ duplicity-backup.sh --restore-file img/mom.jpg
+    $ duplicity-backup.sh [-c config_file] --restore-file img/mom.jpg
     Restores the file img/mom.jpg to the current directory
 
-    $ duplicity-backup.sh --restore-file img/mom.jpg /home/user/i-love-mom.jpg
+    $ duplicity-backup.sh [-c config_file] --restore-file img/mom.jpg /home/user/i-love-mom.jpg
     Restores the file img/mom.jpg to /home/user/i-love-mom.jpg
 
 * List files in the remote archive
-    $ duplicity-backup.sh --list-current-files
+    $ duplicity-backup.sh [-c config_file] --list-current-files
 
 * Verify the backup
-    $ duplicity-backup.sh --verify
+    $ duplicity-backup.sh [-c config_file] --verify
 
 * Backup the script and gpg key (for safekeeping)
-    $ duplicity-backup.sh --backup-script
+    $ duplicity-backup.sh [-c config_file] --backup-script
 
 TROUBLESHOOTING
 ===============

duplicity-backup.sh

@@ -27,14 +27,75 @@
 #
 # ---------------------------------------------------------------------------- #
 
-# Set config file (don't forget to copy duplicity-backup.conf.example to
+# Default config file (don't forget to copy duplicity-backup.conf.example to
-# match that path) 
+# match that path)
+# NOTE: It can be useful not to edit this script at all to ease future updates
+#       so the config file can be specified directly on the command line too 
+#       with the -c option.
 CONFIG="duplicity-backup.conf"
 
 ##############################################################
 # Script Happens Below This Line - Shouldn't Require Editing #
 ##############################################################
 
+# Some expensive argument parsing that allows the script to
+# be insensitive to the order of appearance of the options
+# and to handle correctly option parameters that are optional
+while getopts ":c:-:" opt; do
+  case $opt in
+    # parse long options (a bit tricky because builtin getopts does not
+    # manage long options and i don't want to impose GNU getopt dependancy)
+    -)
+      case "$OPTARG" in
+        backup | full | verify | list-current-files | collection-status | help)
+          COMMAND=$OPTARG
+        ;;
+        # --restore [restore dest]
+        restore)
+          COMMAND=$OPTARG
+          # We try to find the optional value [restore dest]
+          if [ ! -z "${!OPTIND:0:1}" -a ! "${!OPTIND:0:1}" = "-" ]; then
+            RESTORE_DEST=${!OPTIND}
+            OPTIND=$(( $OPTIND + 1 )) # we found it, move forward in arg parsing
+          fi
+        ;;
+        # --restore-file [file to restore] [restore dest]
+        restore-file)
+          COMMAND=$OPTARG
+          # We try to find the first optional value [file to restore]
+          if [ ! -z "${!OPTIND:0:1}" -a ! "${!OPTIND:0:1}" = "-" ]; then
+            FILE_TO_RESTORE=${!OPTIND}
+            OPTIND=$(( $OPTIND + 1 )) # we found it, move forward in arg parsing
+          else
+            continue # no value for the restore-file option, skip the rest
+          fi
+          # We try to find the second optional value [restore dest]
+          if [ ! -z "${!OPTIND:0:1}" -a ! "${!OPTIND:0:1}" = "-" ]; then
+            RESTORE_DEST=${!OPTIND}
+            OPTIND=$(( $OPTIND + 1 )) # we found it, move forward in arg parsing
+          fi
+        ;;
+        *)
+          echo "Invalid option: --$OPTARG" >&2
+          COMMAND=$OPTARG
+        ;;
+        esac
+    ;;
+    # here are parsed the short options
+    c) # set the config file from the command line
+      CONFIG=$OPTARG
+    ;;
+    :)
+      echo "Option -$OPTARG requires an argument." >&2
+      COMMAND=""
+    ;;
+    \?)
+      echo "Invalid option: -$OPTARG" >&2
+      COMMAND=""
+    ;;
+  esac
+done
+
 # Read config file if specified
 if [ ! -z "$CONFIG" -a -f "$CONFIG" ];
 then
@@ -322,13 +383,13 @@ echo -e "--------    START DUPLICITY-BACKUP SCRIPT    --------\n" >> ${LOGFILE}
 
 get_lock
 
-case "$1" in
+case "$COMMAND" in
-  "--backup-script")
+  "backup-script")
     backup_this_script
     exit
   ;;
 
-  "--full")
+  "full")
     OPTION="full"
     include_exclude
     duplicity_backup
@@ -336,7 +397,7 @@ case "$1" in
     get_file_sizes
   ;;
 
-  "--verify")
+  "verify")
     OLDROOT=${ROOT}
     ROOT=${DEST}
     DEST=${OLDROOT}
@@ -355,11 +416,11 @@ case "$1" in
     echo -e "Verify complete.  Check the log file for results:\n>> ${LOGFILE}"
   ;;
 
-  "--restore")
+  "restore")
     ROOT=$DEST
     OPTION="restore"
 
-    if [[ ! "$2" ]]; then
+    if [[ ! "$RESTORE_DEST" ]]; then
       echo "Please provide a destination path (eg, /home/user/dir):"
       read -e NEWDESTINATION
       DEST=$NEWDESTINATION
@@ -372,30 +433,28 @@ case "$1" in
         exit 1
       fi
     else
-      DEST=$2
+      DEST=$RESTORE_DEST
     fi
 
     echo "Attempting to restore now ..."
     duplicity_backup
   ;;
 
-  "--restore-file")
+  "restore-file")
     ROOT=$DEST
     INCLUDE=
     EXCLUDE=
     EXLUDEROOT=
     OPTION=
 
-    if [[ ! "$2" ]]; then
+    if [[ ! "$FILE_TO_RESTORE" ]]; then
       echo "Which file do you want to restore (eg, mail/letter.txt):"
       read -e FILE_TO_RESTORE
       echo
-    else
-      FILE_TO_RESTORE=$2
     fi
 
-    if [[ "$3" ]]; then
+    if [[ "$RESTORE_DEST" ]]; then
-      DEST=$3
+      DEST=$RESTORE_DEST
     else
       DEST=$(basename $FILE_TO_RESTORE)
     fi
@@ -420,7 +479,7 @@ case "$1" in
     duplicity_backup
   ;;
 
-  "--list-current-files")
+  "list-current-files")
     OPTION="list-current-files"
     ${DUPLICITY} ${OPTION} ${VERBOSITY} ${STATIC_OPTIONS} \
     $ENCRYPT \
@@ -428,7 +487,7 @@ case "$1" in
     echo -e "--------    END    --------\n" >> ${LOGFILE}
   ;;
 
-  "--collection-status")
+  "collection-status")
     OPTION="collection-status"
     ${DUPLICITY} ${OPTION} ${VERBOSITY} ${STATIC_OPTIONS} \
     $ENCRYPT \
@@ -436,7 +495,7 @@ case "$1" in
     echo -e "--------    END    --------\n" >> ${LOGFILE}
   ;;
 
-  "--backup")
+  "backup")
     include_exclude
     duplicity_backup
     duplicity_cleanup
@@ -449,6 +508,8 @@ case "$1" in
       `basename $0` [options]
 
     Options:
+      -c config_file : specify the config file to use
+
       --backup: runs an incremental backup
       --full: forces a full backup