don't send to notification endpoints whose token has changed

fixes CNVS-22551

test plan
- see repro step on the ticket
- ensure multiple notifications aren't sent

Change-Id: Ia3e3b5623cd4c8bd78961e1857a045d81b0bc91f
Reviewed-on: https://gerrit.instructure.com/64174
Tested-by: Jenkins
Reviewed-by: Steven Burnett <sburnett@instructure.com>
QA-Review: Adrian Russell <arussell@instructure.com>
Product-Review: Joel Hough <joel@instructure.com>

app/models/notification_endpoint.rb

@@ -29,7 +29,7 @@ class NotificationEndpoint < ActiveRecord::Base
   after_destroy :delete_platform_endpoint
 
   def push_json(json)
-    return false unless endpoint_exists? && own_endpoint? && endpoint_enabled?
+    return false unless endpoint_exists? && own_endpoint? && endpoint_enabled? && !token_changed?
     sns_client.publish(target_arn: self.arn, message: json, message_structure: 'json')
   end
 
@@ -65,6 +65,10 @@ class NotificationEndpoint < ActiveRecord::Base
     endpoint_attributes['Enabled'] == 'true'
   end
 
+  def token_changed?
+    self.token != endpoint_attributes['Token']
+  end
+
   def create_platform_endpoint
     # try to create new or find existing with our access_token
     begin

spec/models/notification_endpoint_spec.rb

@@ -59,6 +59,14 @@ describe NotificationEndpoint do
       ne = @at.notification_endpoints.new(token: 'token')
       expect(ne.push_json('json')).to be_falsey
     end
+
+    it "returns false if the token has changed" do
+      sns_client = mock()
+      sns_client.expects(:get_endpoint_attributes).returns(attributes: {'Enabled' => 'true', 'CustomUserData' => @at.global_id.to_s, 'Token' => 'token2'})
+      NotificationEndpoint.any_instance.expects(:sns_client).returns(sns_client)
+      ne = @at.notification_endpoints.new(token: 'token')
+      expect(ne.push_json('json')).to be_falsey
+    end
   end
 
   describe "#destroy" do