Merge pull request #1601 from FarmBot/log_fix

Prevent background workers from crashing when logs are deleted.

app/lib/log_service.rb

@@ -40,7 +40,7 @@ class LogService < AbstractServiceRunner
   def deliver(data)
     dev, log = [data.device, data.payload]
     dev.maybe_unthrottle
-    Log.deliver(dev, Logs::Create.run!(log, device: dev))
+    Log.deliver(Logs::Create.run!(log, device: dev).id)
     print LOG_TPL % [data.device_id, data.payload["message"] || "??"]
   rescue => x
     Rollbar.error(x)

app/models/log_delivery_stuff.rb

@@ -6,8 +6,9 @@ module LogDeliveryStuff
 
   module ClassMethods
     # If this method grows, create a mutation.
-    def deliver(device, log)
-      send_fatal_emails(log, device)
+    def deliver(log_id)
+      log = Log.find_by(id: log_id)
+      send_fatal_emails(log, log.device) if log
     end
 
     def send_fatal_emails(log, device)

app/mutations/logs/create.rb

@@ -53,7 +53,7 @@ module Logs
     end
 
     def maybe_deliver
-      Log.delay.deliver(device, @log)
+      Log.delay.deliver(@log.id)
     end
 
     def has_bad_words