From 2dfc33b9136b1bec8047382a6daecf3b38f05211 Mon Sep 17 00:00:00 2001
From: Michael Banck <mbanck@debian.org>
Date: Fri, 15 Nov 2019 19:12:14 +0100
Subject: [PATCH]   * debian/pg_createconfig_patroni: Add --vip option and
 write out a     vip-manager configuration if present.   *
 debian/config.yml.in: Add @LISTEN_VIP@ tag.

---
 debian/changelog               |  5 ++-
 debian/config.yml.in           |  2 +-
 debian/pg_createconfig_patroni | 56 ++++++++++++++++++++++++++++++++++
 3 files changed, 61 insertions(+), 2 deletions(-)

diff --git a/debian/changelog b/debian/changelog
index 4d6768d..b1aafd8 100644
--- a/debian/changelog
+++ b/debian/changelog
@@ -1,6 +1,9 @@
 patroni (1.6.0-5) UNRELEASED; urgency=medium
 
-  * 
+  [ Michael Banck ]
+  * debian/pg_createconfig_patroni: Add --vip option and write out a
+    vip-manager configuration if present.
+  * debian/config.yml.in: Add @LISTEN_VIP@ tag.
 
  -- Debian PostgreSQL Maintainers <team+postgresql@tracker.debian.org>  Tue, 08 Oct 2019 12:58:40 +0200
 
diff --git a/debian/config.yml.in b/debian/config.yml.in
index 16d33aa..76c690c 100644
--- a/debian/config.yml.in
+++ b/debian/config.yml.in
@@ -75,7 +75,7 @@ postgresql:
   pg_clonecluster:
     command: /usr/share/patroni/pg_clonecluster_patroni
 
-  listen: "@HOSTIP@,127.0.0.1:@PORT@"
+  listen: "@HOSTIP@@LISTEN_VIP@,127.0.0.1:@PORT@"
   connect_address: @HOSTIP@:@PORT@
   use_unix_socket: true
   data_dir: /var/lib/postgresql/@VERSION@/@CLUSTER@
diff --git a/debian/pg_createconfig_patroni b/debian/pg_createconfig_patroni
index ea32788..0ef1851 100755
--- a/debian/pg_createconfig_patroni
+++ b/debian/pg_createconfig_patroni
@@ -19,6 +19,10 @@ case $i in
     FORCE="y"
     shift # past argument=value
     ;;
+    --vip=*)
+    VIP_IP="${i#*=}"
+    shift # past argument=value
+    ;;
     *)
        # unknown option
     ;;
@@ -78,6 +82,44 @@ if [ $? != 0 ]; then
 fi
 DCS_CONFIG="$(egrep -v '^[[:space:]]*$|^ *#' /etc/patroni/dcs.yml | sed -e ':a;N;$!ba;s/\n/\\n/g' -e 's/\$/\\$/g')"
 
+# check vip configuration
+if [ -n "$VIP_IP" ]; then
+    VIP_FILE=/etc/patroni/${VERSION}-${CLUSTER}.vip
+    if [ ! -e /etc/patroni/vip.in ]; then
+        echo "VIP template /etc/patroni/vip.in does not exist, cannot write VIP file"
+        exit 1
+    fi
+    if [ $(grep -q LISTEN_VIP /etc/patroni/config.yml.in) ]; then
+        echo "Patroni configuration template does not have @LISTEN_VIP@ tag"
+        echo "Postgres will not be able to bind to the VIP $VIP_IP."
+        exit 1
+    fi
+    VIP_IFACE="$(ip -4 route get 8.8.8.8 | grep ^8.8.8.8 | sed -e s/.*dev.// -e s/\ .*//)"
+    if [ -z "$VIP_IFACE" ]; then
+        echo "Network interface could not be determined, cannot write VIP file"
+        exit 1
+    fi
+    VIP_MASK="$(ip -o -f inet addr show $VIP_IFACE | awk '{print $4}' | sed -e 's/.*\///' | uniq)"
+    if [ -z "$VIP_MASK" ]; then
+        echo "Netmask could not be determined, cannot write VIP file"
+        exit 1
+    fi
+    VIP_KEY="/postgresql-common/${VERSION}-${CLUSTER}/leader"
+    DCS_TYPE="$(egrep -v '^[[:space:]]*$|^ *#' /etc/patroni/dcs.yml | egrep '(etcd|consul|zookeeper)' | sed s/:.*//)"
+    if [ -z "$DCS_TYPE" ]; then
+        echo "DCS type could not be determined from /etc/patroni/dcs.yml, cannot write VIP file"
+	exit 1
+    fi
+    DCS_ENDPOINT="$(egrep -v '^[[:space:]]*$|^ *#' /etc/patroni/dcs.yml | grep 'host' | sed -r -e s/.*host:// -e s/-// -e 's/ //g' -e 's/^([0-9])/http:\/\/\1/')"
+    if [ -z "$DCS_ENDPOINT" ]; then
+        echo "DCS endpoint URL could not be determined from /etc/patroni/dcs.yml, cannot write VIP file"
+	exit 1
+    fi
+    LISTEN_VIP=",$VIP_IP"
+else
+    LISTEN_VIP=
+fi
+
 CONFIG_FILE=/etc/patroni/${VERSION}-${CLUSTER}.yml
 
 if [ -f $CONFIG_FILE -a -z "$FORCE" ]; then
@@ -117,12 +159,26 @@ cat /etc/patroni/config.yml.in |		\
         -e "s/@CLUSTER@/${CLUSTER}/g"		\
         -e "s/@HOSTNAME@/${HOSTNAME}/g"		\
         -e "s/@HOSTIP@/${HOSTIP}/g"		\
+        -e "s/@LISTEN_VIP@/${LISTEN_VIP}/g"	\
         -e "s#@NETWORK@#${NETWORK}#g"		\
         -e "s/@API_PORT@/${API_PORT}/g"		\
         -e "s/@PORT@/${PORT}/g"			\
         -e "s/@DCS_CONFIG@/${DCS_CONFIG}/g"	\
 >> $CONFIG_FILE
 
+# write vip configuration, if requested
+if [ -n "$VIP_IP" ]; then
+    cat /etc/patroni/vip.in |				\
+        sed -e "s/@VIP_IP@/${VIP_IP}/g"			\
+            -e "s/@VIP_MASK@/${VIP_MASK}/g"		\
+            -e "s/@VIP_IFACE@/${VIP_IFACE}/g"		\
+            -e "s#@VIP_KEY@#${VIP_KEY}#g"		\
+            -e "s/@VIP_HOST@/${HOSTNAME}/g"		\
+            -e "s/@VIP_TYPE@/${DCS_TYPE}/g"		\
+            -e "s#@VIP_ENDPOINT@#${DCS_ENDPOINT}#g"	\
+    >> $VIP_FILE
+fi
+
 # Set permissions
 chown postgres:postgres $CONFIG_FILE
 chmod 660 $CONFIG_FILE