__nextcloud: move data directory if destination changes

The type now handles the case when the data directory will be moved to
an other location. To this, adjustment to the "maintainer mode" on
setting and the manpage.

type/__nextcloud/gencode-remote

@@ -22,6 +22,28 @@ SU
 SHELL
 }
 
+# Turn the maintainer mode on, but print it only once at all.
+#
+# No arguments.
+occ_maintainer_mode_on() {
+    # Check if this was not already done
+    if [ "$_maintainer_mode_on" != "yes" ]; then
+        occ maintenance:mode --on
+        _maintainer_mode_on="yes"
+    fi
+}
+
+# Print the value of the given configuration.
+#
+# Arguments:
+#  1: the nextcloud configuration name
+getparam() {
+    awk -v FS=" = " -v name="$1" '
+             function ntostring(n) { ret=""; for(i=n; i<=NF; i++) ret=ret $i (i<NF ? OFS : ""); return ret }
+             $1 == name { print ntostring(2); }
+             ' "$__object/explorer/config"
+}
+
 # Get existing versions
 version_is="$( cat "$__object/explorer/version" )"
 version_should="$( cat "$__object/parameter/version" )"
@@ -60,7 +82,7 @@ cd '$updatedir'
 chown '$user':'$group' -R '$tarballdir'
 REMOTE
 
-    occ maintenance:mode --on
+    occ_maintainer_mode_on
     cat << REMOTE
 
 cp -pf '$installdir/config/config.php' '$tarballdir/config/config.php'
@@ -179,6 +201,7 @@ mkdir "$__object/files"
 if [ -s "$__object/files/conf-cmds" ]; then
     # save that we did changes
     changes="yes"
+    occ_maintainer_mode_on
 
     # print change commands incl. the switch of user context
     #  using -e to abort if the commands failed
@@ -186,8 +209,33 @@ if [ -s "$__object/files/conf-cmds" ]; then
     printf "cd '%s'\n" "$installdir"
     cat "$__object/files/conf-cmds"
     printf "SU\n"
+fi
 
-    # print a message
+
+# Get the current and future data directory
+data_old="$(getparam datadirectory)"
+data_new="$(cat "$__object/parameter/data-directory" 2>/dev/null || printf "%s/data" "$installdir")"
+
+# Move if they should be moved. Avoid false positives if $data_old is empty
+if [ "$data_old" ] && [ "$data_old" != "$data_new" ]; then
+    # save that we did changes
+    changes="yes"
+    occ_maintainer_mode_on
+
+    # Change the configuration variable and then move the folder. This order is
+    # important if SQLite is used, but the config already corrupted if it can
+    # not be moved.
+    occ config:system:set datadirectory --type=string --value "'$data_new'"
+    cat << REMOTE
+rm -rf '$data_new'
+mkdir -p '$(dirname "$data_new")'  # if the parent not exists
+mv '$data_old' '$data_new'
+
+REMOTE
+fi
+
+# Print configured message if changes where done to the configuration
+if [ "$changes" ]; then
     echo configured >> "$__messages_out"
 fi
 
@@ -208,6 +256,6 @@ if [ "$install" ]; then
 fi
 
 # Disable maintainer mode
-if [ "$install" ] || [ "$upgrade" ] || [ "$changes" ]; then
+if [ "$_maintainer_mode_on" = "yes" ]; then
     occ maintenance:mode --off
 fi

type/__nextcloud/man.rst

@@ -81,6 +81,15 @@ admin-email
     The email address of the administrative user. This parameter has no effect
     if nextcloud will not be installed.
 
+data-directory
+    This will set or change the data directory where nextcloud will keep all
+    its data, including the SQLite database if any. By default, it will be
+    saved in the ``data`` directory below the nextcloud directory.
+
+    If this directory change, this type will move the old location to the new
+    one to preserve all data. This is not supported by upstream, as some apps
+    may not handle this.
+
 database-type
     Sets the type of database that should be used as backend. Possible backends
     are:
@@ -159,6 +168,11 @@ The type aborts if there is no webroot given as parameter and no could be
 detected by the type itself. Please set the webroot via `--webroot` or extend
 this type.
 
+It may abort if the data directory can not be moved correctly. Then, the
+nextcloud configuration is broken and must be resolved manually: Move the data
+directory to the correct location or change the configuration to point to the
+old destination and retry.
+
 
 EXAMPLES
 --------

type/__nextcloud/map-conf-changes.sh

@@ -84,13 +84,13 @@ conf_base() {
 #  3: conditional mandatory of this parameter; value "required" if true
 #  4: default value; will be used if parameter is absent
 conf_string() {
-    conf_base "$1" "$2" "$3" "$4" "set '%s' --type=string --value='%s'"
+    conf_base "$1" "$2" "$3" "set '%s' --type=string --value='%s'" "$4"
 }
 conf_number() {
-    conf_base "$1" "$2" "$3" "$4" "set '%s' --type=integer --value='%s'"
+    conf_base "$1" "$2" "$3" "set '%s' --type=integer --value='%s'" "$4"
 }
 conf_decimal() {
-    conf_base "$1" "$2" "$3" "$4" "set '%s' --type=double --value='%s'"
+    conf_base "$1" "$2" "$3" "set '%s' --type=double --value='%s'" "$4"
 }
 
 # Sets the nextcloud configuration option after a boolean cdist parameter.
@@ -232,6 +232,6 @@ if [ -z "$install" ]; then
             ;;
     esac
 
-    # data-dir
-    conf_string data-directory datadirectory installdef "$(cat "$__object/explorer/installdir")/$__object_id/data"
+    # data-dir is handled in the gencode-remote
+    #conf_string data-directory datadirectory installdef "$(cat "$__object/explorer/installdir")/$__object_id/data"
 fi