From 06eb4f10f3e8bddc00d303d867b157d96e66c69b Mon Sep 17 00:00:00 2001
From: Philippe Pittoli <karchnu@karchnu.fr>
Date: Sat, 23 Nov 2024 15:06:33 +0100
Subject: [PATCH] Deployment scripts.

---
 deployment/primary-watchdog.sh   | 64 ++++++++++++++++++++++++++++++++
 deployment/secondary-watchdog.sh | 42 +++++++++++++++++++++
 2 files changed, 106 insertions(+)
 create mode 100755 deployment/primary-watchdog.sh
 create mode 100755 deployment/secondary-watchdog.sh

diff --git a/deployment/primary-watchdog.sh b/deployment/primary-watchdog.sh
new file mode 100755
index 0000000..7f6d1a6
--- /dev/null
+++ b/deployment/primary-watchdog.sh
@@ -0,0 +1,64 @@
+#!/bin/sh
+
+# Watchdog for the primary name server.
+
+REMOTE="gandi"
+REMOTE_DIR="/var/powerdns/"
+DIR="$REMOTE_DIR"
+
+echo "directory: $DIR"
+
+local_update() {
+	echo "local update of domain $1"
+	pdns_control bind-reload-now $1
+
+	# In case the update cannot be done, it might be because the zone wasn't loaded at all.
+	if [ $? -ne 0 ]; then
+		pdns_control bind-add-zone $1 $DIR/$1
+	fi
+}
+
+local_delete() {
+	echo "TODO: local delete of domain $1"
+}
+
+remote_update() {
+	echo "remote update on $REMOTE $REMOTE_DIR/$1"
+	scp $DIR/$1 $REMOTE:$REMOTE_DIR
+}
+
+remote_delete() {
+	echo "remote delete on $REMOTE $REMOTE_DIR/$1"
+	ssh $REMOTE rm $REMOTE_DIR/$1
+}
+
+action() {
+	event=$1
+	file=$2
+
+	echo $event | grep "MOVED_TO" >/dev/null
+	if [ $? -eq 0 ]; then
+		echo "$file has been modified"
+		local_update $file
+		remote_update $file
+	fi
+
+	echo $event | grep "DELETE" >/dev/null
+	if [ $? -eq 0 ]; then
+		echo "$file has been deleted"
+		local_delete $file
+		remote_delete $file
+	fi
+}
+
+# NOTE: dnsmanagerd writes bind9 files in $DIR and with a suffix ".wip" then moves them
+#       to remove the suffix. This way, the final file is expected to never be corrupted,
+#       for example by copying it to the secondary DNS server while the zone not being
+#       fully written to the file.
+#
+# Therefore, the different interesting actions we should monitor are:
+# - moved_to: a zone file has been modified
+# - delete: a domain has been removed
+opts="-e moved_to -e delete -m"
+echo "inotifywait ${opts} --format '%:e %f' $DIR"
+inotifywait ${opts} --format '%:e %f' $DIR | while read FILE; do action $FILE ; done
diff --git a/deployment/secondary-watchdog.sh b/deployment/secondary-watchdog.sh
new file mode 100755
index 0000000..10b2d12
--- /dev/null
+++ b/deployment/secondary-watchdog.sh
@@ -0,0 +1,42 @@
+#!/bin/sh
+
+# Primary sends files in $DIR.
+DIR="/var/powerdns/"
+
+local_update() {
+	echo "update domain $1"
+	pdns_control bind-reload-now $1
+
+	# In case the update cannot be done, it might be because the zone wasn't loaded at all.
+	if [ $? -ne 0 ]; then
+		pdns_control bind-add-zone $1 $DIR/$1
+	fi
+}
+
+local_delete() { echo "TODO: delete domain $1" ; }
+
+action() {
+	event=$1
+	file=$2
+
+	echo $event | grep "CLOSE_WRITE" >/dev/null
+	if [ $? -eq 0 ]; then
+		echo "$file has been modified"
+		local_update $file
+	fi
+
+	echo $event | grep "DELETE" >/dev/null
+	if [ $? -eq 0 ]; then
+		echo "$file has been deleted"
+		local_delete $file
+	fi
+}
+
+# NOTE: primary nameserver sends files in $DIR upon modification or remove them
+#
+# Therefore, the different interesting actions we should monitor are:
+# - close_write: a zone file has been modified
+# - delete: a domain has been removed
+opts="-e close_write -e delete -m"
+echo "inotifywait ${opts} --format '%:e %f' $DIR"
+inotifywait ${opts} --format '%:e %f' $DIR | while read FILE; do action $FILE ; done