Add interruption hook

lib/job-iteration/iteration.rb

@@ -59,6 +59,18 @@ def on_complete(*filters, &blk)
         set_callback(:complete, :after, *filters, &blk)
       end
 
+      def stop_iterating_on(interrupt_proc)
+        interruptors << interrupt_proc
+      end
+
+      def interruptors
+        @interruptors ||= [
+          ->(job) { JobIteration.max_job_runtime && job.start_time && (Time.now.utc - job.start_time) > JobIteration.max_job_runtime },
+          ->(_) { JobIteration.interruption_adapter.call },
+        ]
+        @interruptors
+      end
+
       private
 
       def ban_perform_definition
@@ -256,11 +268,8 @@ def output_interrupt_summary
     end
 
     def job_should_exit?
-      if ::JobIteration.max_job_runtime && start_time && (Time.now.utc - start_time) > ::JobIteration.max_job_runtime
-        return true
-      end
-
-      JobIteration.interruption_adapter.call || (defined?(super) && super)
+      self.class.interruptors.any? { |interrupt_proc| interrupt_proc.call(self) } ||
+        (defined?(super) && super)
     end
 
     def run_complete_callbacks?(completed)

test/unit/iteration_test.rb

@@ -138,6 +138,27 @@ def each_iteration(*)
     end
   end
 
+  class JobThatInterruptsItself < ActiveJob::Base
+    include JobIteration::Iteration
+
+    cattr_accessor :iterations_performed, instance_accessor: false
+    self.iterations_performed = []
+
+    stop_iterating_on(->(job) { job.class.iterations_performed.size >= 1 })
+
+    def build_enumerator(_params, cursor:)
+      enumerator_builder.build_array_enumerator([1, 2, 3], cursor: cursor)
+    end
+
+    def each_iteration(record, _params)
+      self.class.iterations_performed << record
+    end
+  end
+
+  setup do
+    JobThatInterruptsItself.iterations_performed = []
+  end
+
   def test_jobs_that_define_build_enumerator_and_each_iteration_will_not_raise
     push(JobWithRightMethods, "walrus" => "best")
     work_one_job
@@ -242,6 +263,12 @@ def test_jobs_using_on_complete_have_accurate_total_time
     end
   end
 
+  def test_jobs_can_define_custom_interruption_triggers
+    JobThatInterruptsItself.perform_now({})
+
+    assert_equal([1], JobThatInterruptsItself.iterations_performed)
+  end
+
   private
 
   def assert_raises_cursor_error(&block)