Restart agent on debian package upgrade (#1826)

Author: dricross

Tools/src/create_deb.sh

@@ -52,6 +52,7 @@ mkdir -p ${BUILD_ROOT}/var/run/amazon
 ln -f -s /opt/aws/amazon-cloudwatch-agent/var ${BUILD_ROOT}/var/run/amazon/amazon-cloudwatch-agent
 
 cp ${BUILD_SPACE}/packaging/debian/conffiles ${BUILD_ROOT}/
+cp ${BUILD_SPACE}/packaging/debian/postinst ${BUILD_ROOT}/
 cp ${BUILD_SPACE}/packaging/debian/preinst ${BUILD_ROOT}/
 cp ${BUILD_SPACE}/packaging/debian/prerm ${BUILD_ROOT}/
 cp ${BUILD_SPACE}/packaging/debian/debian-binary ${BUILD_ROOT}/
@@ -79,7 +80,7 @@ cd ${BUILD_ROOT}
 tar czf data.tar.gz opt etc usr var --owner=0 --group=0
 cd ~-
 cd ${BUILD_ROOT}
-tar czf control.tar.gz control conffiles preinst prerm --owner=0 --group=0
+tar czf control.tar.gz control conffiles postinst preinst prerm --owner=0 --group=0
 cd ~-
 
 echo "Creating the debian package"

packaging/debian/postinst

@@ -0,0 +1,14 @@
+#!/bin/sh
+# Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+# SPDX-License-Identifier: MIT
+
+set -e
+
+# restart agent after upgrade
+if [ "$1" = "configure" ]; then
+     if [ -x /opt/aws/amazon-cloudwatch-agent/bin/amazon-cloudwatch-agent-ctl ]; then
+          /opt/aws/amazon-cloudwatch-agent/bin/amazon-cloudwatch-agent-ctl -a cond-restart
+     fi
+fi
+
+exit 0