fix check miners

lib/tasks/miners.rake

@@ -4,7 +4,7 @@ namespace :miners do
     response = HTTParty.get(url)
 
     response_json = JSON.parse(response.body)
-    time = DateTime.new
+    time = DateTime.now
     miners = Miner.all
 
     if response_json == []
@@ -17,6 +17,7 @@ namespace :miners do
       is_work = false
       hr_stats = 0
       check_activity_time = (DateTime.now - 5.minutes)
+      last_activity_time = miner.last_activity || check_activity_time
 
       response_json.each do |item|
         if item['work_id'] == miner.name
@@ -29,7 +30,7 @@ namespace :miners do
       if is_work
         miner.update(status: 'work', hash_rate: hr_stats)
       else
-        if miner.last_activity < check_activity_time
+        if last_activity_time <= check_activity_time
           miner.update(status: 'miss', last_activity: time, hash_rate: hr_stats)
         end
       end