How can I detect that a record was created by a trigger without creating custom fields?

Question

I have two triggers:

1. First trigger fires on lead update. It creates a task when lead is converted and links the created task to the contact resulting from the conversion.
2. Second trigger fires on Task update. It closes all opportunities related to the account of the contact linked in the task.

The problem is that the second trigger must only do its job on tasks created by the first trigger, not tasks created through the UI or any other how.

How can I detect in the second trigger that a task was created by the first trigger, knowing that I don't have enough permissions to :

• add custom fields to the task object
• create custom objects that can refer to the task object

Any help is of tremendously appreciated.

Answer 1

Use a static variable.

// Static variable class
public class SystemFlags {
  public static Boolean tasksCreatedFromTrigger = false;
}

...

// Lead trigger logic
SystemFlags.tasksCreatedFromTrigger = true;
insert taskList;

...

// Task trigger logic
if(SystemFlags.tasksCreatedFromTrigger) {
  updateRelatedOpportunities(taskList);
}

Obviously, this is all just generic code, but the idea is that we can communicate across triggers by using static memory in a shared utility class.