fix aws sns topic subscribe (#193)

Author: davehorton

lib/autoscale-manager.js

@@ -8,7 +8,7 @@ module.exports = (logger) => {
   // listen for SNS lifecycle changes
   let lifecycleEmitter = new Emitter();
   lifecycleEmitter.dryUpCalls = false;
-  if (process.env.AWS_SNS_TOPIC_ARM) {
+  if (process.env.AWS_SNS_TOPIC_ARN) {
 
     (async function() {
       try {

lib/aws-sns-lifecycle.js

@@ -69,7 +69,17 @@ class SnsNotifier extends Emitter {
             subscriptionRequestId: this.subscriptionRequestId
           }, 'response from SNS SubscribeURL');
           const data = await this.describeInstance();
-          this.lifecycleState = data.AutoScalingGroups[0].Instances[0].LifecycleState;
+
+          const group = data.AutoScalingGroups.find((group) =>
+            group.Instances && group.Instances.some((instance) => instance.InstanceId === this.instanceId)
+          );
+          if (!group) {
+            this.logger.error('Current instance not found in any Auto Scaling group', data);
+          } else {
+            const instance = group.Instances.find((instance) => instance.InstanceId === this.instanceId);
+            this.lifecycleState = instance.LifecycleState;
+          }
+
           this.emit('SubscriptionConfirmation', {publicIp: this.publicIp});
           break;
 
@@ -137,13 +147,13 @@ class SnsNotifier extends Emitter {
     try {
       const params = {
         Protocol: 'http',
-        TopicArn: process.env.AWS_SNS_TOPIC_ARM,
+        TopicArn: process.env.AWS_SNS_TOPIC_ARN,
         Endpoint: this.snsEndpoint
       };
       const response = await snsClient.send(new SubscribeCommand(params));
-      this.logger.info({response}, `response to SNS subscribe to ${process.env.AWS_SNS_TOPIC_ARM}`);
+      this.logger.info({response}, `response to SNS subscribe to ${process.env.AWS_SNS_TOPIC_ARN}`);
     } catch (err) {
-      this.logger.error({err}, `Error subscribing to SNS topic arn ${process.env.AWS_SNS_TOPIC_ARM}`);
+      this.logger.error({err}, `Error subscribing to SNS topic arn ${process.env.AWS_SNS_TOPIC_ARN}`);
     }
   }
 
@@ -154,9 +164,9 @@ class SnsNotifier extends Emitter {
         SubscriptionArn: this.subscriptionArn
       };
       const response = await snsClient.send(new UnsubscribeCommand(params));
-      this.logger.info({response}, `response to SNS unsubscribe to ${process.env.AWS_SNS_TOPIC_ARM}`);
+      this.logger.info({response}, `response to SNS unsubscribe to ${process.env.AWS_SNS_TOPIC_ARN}`);
     } catch (err) {
-      this.logger.error({err}, `Error unsubscribing to SNS topic arn ${process.env.AWS_SNS_TOPIC_ARM}`);
+      this.logger.error({err}, `Error unsubscribing to SNS topic arn ${process.env.AWS_SNS_TOPIC_ARN}`);
     }
   }