added condition if empty asg

automate-launch-configuration-update-with-latest-image/automate-launch-configuration-update-with-latest-image.sh

@@ -23,6 +23,7 @@ else
 	# export AWS PROFILES
 	export AWS_PROFILE="$1"
 	export AWS_REGION="$2"
+	export DATETODAY=$(date +%d%m%Y)
 
 	# Enter ASG Name
 	export ASG_NAME="$3"
@@ -32,8 +33,6 @@ else
 	alias aws=''`which aws`' --region '"$AWS_REGION"' --output text --profile '"$AWS_PROFILE"''
 	shopt -s expand_aliases
 
-	DATETODAY=$(date +%d%m%Y)
-	DATEYESTERDAY=$(date +%d%m%Y --date='yesterday')
 
 	# Get launch configuration name from ASG_NAME
 	LC_NAME="$(aws autoscaling describe-auto-scaling-groups --auto-scaling-group-names $ASG_NAME --output text --query 'AutoScalingGroups[].LaunchConfigurationName')"
@@ -42,34 +41,39 @@ else
 	# Get 1 random instance ID from the list of instances running under ASG_NAME
 	RANDOM_INST_ID="$(aws autoscaling describe-auto-scaling-groups --auto-scaling-group-names $ASG_NAME --output text --query 'AutoScalingGroups[].Instances[?HealthStatus==`Healthy`].InstanceId' | tr -s '\t' '\n' | shuf -n 1)"
 
-	# Create AMI from the Instance without reboot
-	AMI_ID="$(aws ec2 create-image --instance-id $RANDOM_INST_ID --name "$ASG_NAME"-"$DATETODAY" --output text --no-reboot)"
-
-	# Extract existing launch configuration
-	aws autoscaling describe-launch-configurations --launch-configuration-names $LC_NAME --output json --query 'LaunchConfigurations[0]' > /tmp/$LC_NAME.json
-
-	# Remove unnecessary and empty entries from the launch configuration JSON and fill up with latest AMI ID
-	cat /tmp/$LC_NAME.json | \
-		jq 'walk(if type == "object" then with_entries(select(.value != null and .value != "" and .value != [] and .value != {} and .value != [""] )) else . end )' | \
-		jq 'del(.CreatedTime, .LaunchConfigurationARN)' | \
-		jq ".ImageId = \"$AMI_ID\" | .LaunchConfigurationName = \"$NEW_LC_NAME\"" > /tmp/$NEW_LC_NAME.json
-
-	# Create new launch configuration with new name
-	if [ -z "$(jq .UserData /tmp/$LC_NAME.json --raw-output)" ]; then
-		aws autoscaling create-launch-configuration \
-			--cli-input-json file:///tmp/$NEW_LC_NAME.json
+	if [ -z "$RANDOM_INST_ID" ]; then
+		echo "No instances running in this ASG; Quitting"
+		exit 1
 	else
-		aws autoscaling create-launch-configuration \
-			--cli-input-json file:///tmp/$NEW_LC_NAME.json \
-			--user-data file://<(jq .UserData /tmp/$NEW_LC_NAME.json --raw-output | base64 --decode)
-	fi
-
-	# Update autoscaling group with new launch configuration
-	aws autoscaling update-auto-scaling-group --auto-scaling-group-name "$ASG_NAME" --launch-configuration-name "$NEW_LC_NAME"
+		# Create AMI from the Instance without reboot
+		AMI_ID="$(aws ec2 create-image --instance-id $RANDOM_INST_ID --name "$ASG_NAME"-"$DATETODAY" --output text --no-reboot)"
+
+		# Extract existing launch configuration
+		aws autoscaling describe-launch-configurations --launch-configuration-names $LC_NAME --output json --query 'LaunchConfigurations[0]' > /tmp/$LC_NAME.json
 
-	# Delete old launch configuration
-	#aws autoscaling delete-launch-configuration --launch-configuration-name "$LC_NAME_OLD"
+		# Remove unnecessary and empty entries from the launch configuration JSON and fill up with latest AMI ID
+		cat /tmp/$LC_NAME.json | \
+			jq 'walk(if type == "object" then with_entries(select(.value != null and .value != "" and .value != [] and .value != {} and .value != [""] )) else . end )' | \
+			jq 'del(.CreatedTime, .LaunchConfigurationARN)' | \
+			jq ".ImageId = \"$AMI_ID\" | .LaunchConfigurationName = \"$NEW_LC_NAME\"" > /tmp/$NEW_LC_NAME.json
 
-	# Resetting aws binary alias
-	unalias aws
+		# Create new launch configuration with new name
+		if [ -z "$(jq .UserData /tmp/$LC_NAME.json --raw-output)" ]; then
+			aws autoscaling create-launch-configuration \
+				--cli-input-json file:///tmp/$NEW_LC_NAME.json
+		else
+			aws autoscaling create-launch-configuration \
+				--cli-input-json file:///tmp/$NEW_LC_NAME.json \
+				--user-data file://<(jq .UserData /tmp/$NEW_LC_NAME.json --raw-output | base64 --decode)
+		fi
+
+		# Update autoscaling group with new launch configuration
+		aws autoscaling update-auto-scaling-group --auto-scaling-group-name "$ASG_NAME" --launch-configuration-name "$NEW_LC_NAME"
+
+		# Delete old launch configuration
+		#aws autoscaling delete-launch-configuration --launch-configuration-name "$LC_NAME_OLD"
+
+		# Resetting aws binary alias
+		unalias aws
+	fi
 fi