complete rewrite: use state explorer to determine current state, more robust implementation for adding, changing, removing key/values

Signed-off-by: Steven Armstrong <steven@icarus.ethz.ch>

conf/type/__key_value/explorer/state

@@ -17,19 +17,34 @@
 # You should have received a copy of the GNU General Public License
 # along with cdist. If not, see <http://www.gnu.org/licenses/>.
 #
-#
-# Get the current value of key or __NOTSET__ if the key doesn't exist.
-#
 
 key="$(cat "$__object/parameter/key" 2>/dev/null \
    || echo "$__object_id")"
-
+state="$(cat "$__object/parameter/state" 2>/dev/null \
+   || echo "present")"
 file="$(cat "$__object/parameter/file")"
 delimiter="$(cat "$__object/parameter/delimiter")"
+value="$(cat "$__object/parameter/value" 2>/dev/null \
+   || echo "__CDIST_NOTSET__")"
 
-awk -F "$delimiter" '
-BEGIN { found=0 }
-/^'$key'/ { print $2; found=1 }
-END { if (found) exit 0; else exit 1 }' "$file" \
-|| echo "__NOTSET__"
-
+case "$state" in
+   absent)
+      # if the key exists, with whatever value, we will have to remove it
+      # so report it as present
+      if egrep -q "^$key$delimiter+" "$file"; then
+         echo present
+      fi
+   ;;
+   present)
+      if egrep -q "^$key$delimiter+$value$" "$file"; then
+         # key exists and value is same
+         echo present
+      elif egrep -q "^$key$delimiter+" "$file"; then
+         # key exists, but value is empty or different
+         echo wrongvalue
+      else
+         # key does not exist
+         echo absent
+      fi
+   ;;
+esac

conf/type/__key_value/gencode-remote

@@ -18,32 +18,40 @@
 # along with cdist. If not, see <http://www.gnu.org/licenses/>.
 #
 
-value_is="$(cat "$__object/explorer/value")"
-value_should="$(cat "$__object/parameter/value")"
-
 key="$(cat "$__object/parameter/key")"
 file="$(cat "$__object/parameter/file")"
 delimiter="$(cat "$__object/parameter/delimiter")"
+value="$(cat "$__object/parameter/value")"
 
-if [ "$value_is" != "$value_should" ]; then
-   case "$value_is" in
-      __NOTSET__)
-         # add key and value
-         echo "echo \"${key}${delimiter}${value_should}\" >> \"$file\""
-      ;;
-      *)
-         if [ "$value_should" = '__NOTSET__' ]; then
-            # remove key and value
-            cat << DONE
-sed -i '/^${key}/d' "$file"
-DONE
-         else
-            # change value
-            cat << DONE
-sed -i "s|^$key\($delimiter\+\).*|$key\1$value_should|" "$file"
-DONE
-         fi
-      ;;
-   esac
+state_is="$(cat "$__object/explorer/state")"
+state_should="$(cat "$__object/parameter/state")"
+
+if [ "$state_is" = "$state_should" ]; then
+   # nothing to do
+   exit 0
 fi
 
+case "$state_should" in
+   absent)
+      # remove lines starting with key
+      echo "sed -i '/^$key\($delimiter\+\)/d' \"$file\""
+   ;;
+   present)
+      case "$state_is" in
+         absent)
+            # add new key and value
+            echo "echo \"${key}${delimiter}${value}\" >> \"$file\""
+         ;;
+         wrongvalue)
+            # change exisiting value
+            echo "sed -i \"s|^$key\($delimiter\+\).*|$key\1$value|\" \"$file\""
+         ;;
+         *)
+            echo "Unknown explorer state: $state_is" >&2
+            exit 1
+      esac
+   ;;
+   *)
+      echo "Unknown state: $state_should" >&2
+      exit 1
+esac 

conf/type/__key_value/man.text

@@ -16,9 +16,6 @@ file.
 
 REQUIRED PARAMETERS
 -------------------
-value::
-   The value for the key. Setting the value to `__NOTSET__` will remove the key
-   from the file.
 file::
    The file to operate on.
 delimiter::
@@ -27,8 +24,13 @@ delimiter::
 
 OPTIONAL PARAMETERS
 -------------------
+state::
+   present or absent, defaults to present. If present, sets the key to value,
+   if absent, removes the key from the file.
 key::
    The key to change. Defaults to object_id.
+value::
+   The value for the key. Optional if state=absent, required otherwise.
 
 
 EXAMPLES
@@ -45,6 +47,9 @@ __key_value my-fancy-id --file /etc/login.defs --key SYS_UID_MAX --value 666 \
 # Enable packet forwarding
 __key_value net.ipv4.ip_forward --file /etc/sysctl.conf --value 1 \
    --delimiter '='
+
+# Remove existing key/value
+__key_value LEGACY_KEY --file /etc/somefile --state absent --delimiter '=' 
 --------------------------------------------------------------------------------
 
 

conf/type/__key_value/manifest

@@ -19,5 +19,12 @@
 #
 
 # set defaults
-[ -f "$__object/parameter/key" ] \
-   || echo "$__object_id" > "$__object/parameter/key"
+key="$(cat "$__object/parameter/key" 2>/dev/null \
+   || echo "$__object_id" | tee "$__object/parameter/key")"
+state="$(cat "$__object/parameter/state" 2>/dev/null \
+   || echo "present" | tee "$__object/parameter/state")"
+
+if [ "$state" = "present" -a ! -f "$__object/parameter/value" ]; then
+   echo "Missing required parameter 'value'" >&2
+   exit 1
+fi 

conf/type/__key_value/parameter/optional

@@ -1 +1,3 @@
 key
+value
+state

conf/type/__key_value/parameter/required

@@ -1,3 +1,2 @@
-value
 file
 delimiter