From 85f7880c7ed4b86453e837bc781861ac0cd694e5 Mon Sep 17 00:00:00 2001
From: Steven Armstrong <steven@icarus.ethz.ch>
Date: Fri, 3 Feb 2012 20:50:17 +0100
Subject: [PATCH 1/5] add a hopefully more robust implementation for changing
 existing values

Signed-off-by: Steven Armstrong <steven@icarus.ethz.ch>
---
 conf/type/__key_value/gencode-remote | 5 +----
 1 file changed, 1 insertion(+), 4 deletions(-)

diff --git a/conf/type/__key_value/gencode-remote b/conf/type/__key_value/gencode-remote
index eff0925c..08b3a0f3 100755
--- a/conf/type/__key_value/gencode-remote
+++ b/conf/type/__key_value/gencode-remote
@@ -40,10 +40,7 @@ DONE
          else
             # change value
             cat << DONE
-awk -F "$delimiter" '
-/${key}${delimiter}*/{gsub("$value_is", "$value_should")};{print}' "$file" > "${file}+" \
-&& mv "${file}+" "$file"
-
+sed -i "s|^$key\($delimiter\+\).*|$key\1$value_should|" "$file"
 DONE
          fi
       ;;

From 4628dad04576103945553609c9e46c71cee35de8 Mon Sep 17 00:00:00 2001
From: Steven Armstrong <steven@icarus.ethz.ch>
Date: Fri, 3 Feb 2012 20:55:24 +0100
Subject: [PATCH 2/5] cleaner way to set default values

Signed-off-by: Steven Armstrong <steven@icarus.ethz.ch>
---
 conf/type/__key_value/explorer/value | 8 +++-----
 conf/type/__key_value/manifest       | 9 +++------
 2 files changed, 6 insertions(+), 11 deletions(-)

diff --git a/conf/type/__key_value/explorer/value b/conf/type/__key_value/explorer/value
index 3afc7cc5..b4e1fafd 100755
--- a/conf/type/__key_value/explorer/value
+++ b/conf/type/__key_value/explorer/value
@@ -21,11 +21,9 @@
 # Get the current value of key or __NOTSET__ if the key doesn't exist.
 #
 
-if [ -f "$__object/parameter/key" ]; then
-   key="$(cat "$__object/parameter/key")"
-else
-   key="$__object_id"
-fi
+key="$(cat "$__object/parameter/key" 2>/dev/null \
+   || echo "$__object_id")"
+
 file="$(cat "$__object/parameter/file")"
 delimiter="$(cat "$__object/parameter/delimiter")"
 
diff --git a/conf/type/__key_value/manifest b/conf/type/__key_value/manifest
index 706b0b0d..84c06352 100755
--- a/conf/type/__key_value/manifest
+++ b/conf/type/__key_value/manifest
@@ -18,9 +18,6 @@
 # along with cdist. If not, see <http://www.gnu.org/licenses/>.
 #
 
-if [ -f "$__object/parameter/key" ]; then
-   key="$(cat "$__object/parameter/key")"
-else
-   echo "$__object_id" > "$__object/parameter/key"
-fi
-
+# set defaults
+[ -f "$__object/parameter/key" ] \
+   || echo "$__object_id" > "$__object/parameter/key"

From cad2097d0559861f66a988c88c4022721fa8c033 Mon Sep 17 00:00:00 2001
From: Steven Armstrong <steven@icarus.ethz.ch>
Date: Fri, 3 Feb 2012 22:43:34 +0100
Subject: [PATCH 3/5] 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>
---
 .../__key_value/explorer/{value => state}     | 35 ++++++++----
 conf/type/__key_value/gencode-remote          | 54 +++++++++++--------
 conf/type/__key_value/man.text                | 11 ++--
 conf/type/__key_value/manifest                | 11 +++-
 conf/type/__key_value/parameter/optional      |  2 +
 conf/type/__key_value/parameter/required      |  1 -
 6 files changed, 75 insertions(+), 39 deletions(-)
 rename conf/type/__key_value/explorer/{value => state} (54%)

diff --git a/conf/type/__key_value/explorer/value b/conf/type/__key_value/explorer/state
similarity index 54%
rename from conf/type/__key_value/explorer/value
rename to conf/type/__key_value/explorer/state
index b4e1fafd..7e66cb69 100755
--- a/conf/type/__key_value/explorer/value
+++ b/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
diff --git a/conf/type/__key_value/gencode-remote b/conf/type/__key_value/gencode-remote
index 08b3a0f3..0846dca1 100755
--- a/conf/type/__key_value/gencode-remote
+++ b/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 
diff --git a/conf/type/__key_value/man.text b/conf/type/__key_value/man.text
index 3e4e8013..1423fc7d 100644
--- a/conf/type/__key_value/man.text
+++ b/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 '=' 
 --------------------------------------------------------------------------------
 
 
diff --git a/conf/type/__key_value/manifest b/conf/type/__key_value/manifest
index 84c06352..2e75e175 100755
--- a/conf/type/__key_value/manifest
+++ b/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 
diff --git a/conf/type/__key_value/parameter/optional b/conf/type/__key_value/parameter/optional
index 06bfde49..483e3192 100644
--- a/conf/type/__key_value/parameter/optional
+++ b/conf/type/__key_value/parameter/optional
@@ -1 +1,3 @@
 key
+value
+state
diff --git a/conf/type/__key_value/parameter/required b/conf/type/__key_value/parameter/required
index 8f4aa53c..3ae10da3 100644
--- a/conf/type/__key_value/parameter/required
+++ b/conf/type/__key_value/parameter/required
@@ -1,3 +1,2 @@
-value
 file
 delimiter

From ef81f03e89a2b53498f52d2e6262ea0ec94afdd4 Mon Sep 17 00:00:00 2001
From: Steven Armstrong <steven@icarus.ethz.ch>
Date: Fri, 3 Feb 2012 22:49:10 +0100
Subject: [PATCH 4/5] have to report absent state no matter what the desired
 state is

Signed-off-by: Steven Armstrong <steven@icarus.ethz.ch>
---
 conf/type/__key_value/explorer/state | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/conf/type/__key_value/explorer/state b/conf/type/__key_value/explorer/state
index 7e66cb69..ec760f71 100755
--- a/conf/type/__key_value/explorer/state
+++ b/conf/type/__key_value/explorer/state
@@ -29,10 +29,13 @@ value="$(cat "$__object/parameter/value" 2>/dev/null \
 
 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
+         # if the key exists, with whatever value, we will have to remove it
+         # so report it as present
          echo present
+      else
+         # key does not exist
+         echo absent
       fi
    ;;
    present)

From 817ce9c2562cc24117702a3eac7c3717766d0a87 Mon Sep 17 00:00:00 2001
From: Steven Armstrong <steven@icarus.ethz.ch>
Date: Wed, 8 Feb 2012 08:31:59 +0100
Subject: [PATCH 5/5] /egrep/grep -E/

Signed-off-by: Steven Armstrong <steven@icarus.ethz.ch>
---
 conf/type/__key_value/explorer/state | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

diff --git a/conf/type/__key_value/explorer/state b/conf/type/__key_value/explorer/state
index ec760f71..94a5ea7f 100755
--- a/conf/type/__key_value/explorer/state
+++ b/conf/type/__key_value/explorer/state
@@ -29,7 +29,7 @@ value="$(cat "$__object/parameter/value" 2>/dev/null \
 
 case "$state" in
    absent)
-      if egrep -q "^$key$delimiter+" "$file"; then
+      if grep -q -E "^$key$delimiter+" "$file"; then
          # if the key exists, with whatever value, we will have to remove it
          # so report it as present
          echo present
@@ -39,10 +39,10 @@ case "$state" in
       fi
    ;;
    present)
-      if egrep -q "^$key$delimiter+$value$" "$file"; then
+      if grep -q -E "^$key$delimiter+$value$" "$file"; then
          # key exists and value is same
          echo present
-      elif egrep -q "^$key$delimiter+" "$file"; then
+      elif grep -q -E "^$key$delimiter+" "$file"; then
          # key exists, but value is empty or different
          echo wrongvalue
       else