Moved notification about negative account balance to background.

app/models/ordergroup.rb

@@ -43,12 +43,15 @@ class Ordergroup < Group
   # Throws an exception if it fails.
   def add_financial_transaction!(amount, note, user)
     transaction do      
-      trans = FinancialTransaction.new(:ordergroup => self, :amount => amount, :note => note, :user => user)
-      trans.save!
+      t = FinancialTransaction.new(:ordergroup => self, :amount => amount, :note => note, :user => user)
+      t.save!
       self.account_balance = financial_transactions.sum('amount')
-      self.account_updated = trans.created_on
+      self.account_updated = t.created_on
       save!
-      notify_negative_balance(trans)
+      # Notify only when order group had a positive balance before the last transaction:
+      if t.amount < 0 && self.account_balance < 0 && self.account_balance - t.amount >= 0
+        UserNotifier.delay.negative_balance(self.id, t.id)
+      end
     end
   end
 
@@ -76,17 +79,6 @@ class Ordergroup < Group
   end
   
   private
-  
-  # If this order group's account balance is made negative by the given/last transaction, 
-  # a message is sent to all users who have enabled notification.
-  def notify_negative_balance(transaction)
-    # Notify only when order group had a positive balance before the last transaction:
-    if (transaction.amount < 0 && self.account_balance < 0 && self.account_balance - transaction.amount >= 0)
-      for user in users
-        Mailer.negative_balance(user,transaction).deliver if user.settings["notify.negativeBalance"] == '1'
-      end
-    end
-  end
 
   # Make sure, that a user can only be in one ordergroup
   def uniqueness_of_members

app/models/user_notifier.rb

@@ -12,4 +12,18 @@ class UserNotifier
       end
     end
   end
+
+  # If this order group's account balance is made negative by the given/last transaction,
+  # a message is sent to all users who have enabled notification.
+  def self.negative_balance(ordergroup_id, transaction_id)
+    transaction = FinancialTransaction.find transaction_id
+
+    Ordergroup.find(ordergroup_id).users.each do |user|
+      begin
+        Mailer.negative_balance(user, transaction).deliver if user.settings["notify.negativeBalance"] == '1'
+      rescue
+        Rails.logger.warn "Can't deliver mail to #{user.email}"
+      end
+    end
+  end
 end