Allow maximum number of workers to be configured per job type.

README.md

@@ -115,6 +115,30 @@ it.
 
 If you don't want more than one job running at a time then set this to 1.
 
+Beyond this global scope you can adjust the total number of workers on each
+individual Resque Job type by overriding the `max_workers` class method for the job.
+If you change this, the value returned by that method takes precedence over the
+global value.
+
+```ruby
+class ResourceIntensiveJob
+  extend Resque::Kubernetes::Job
+
+  def perform
+    # ...
+  end
+
+  def job_manifest
+    # ...
+  end
+
+  def max_workers
+    # Simply return an integer value, or do something more complicated if needed.
+    105
+  end
+end
+```
+
 ## To Do
 
 - We probably need better namespace support, particularly for reaping 

lib/resque/kubernetes/job.rb

@@ -49,6 +49,32 @@ def before_enqueue_kubernetes_job(*_)
         apply_kubernetes_job
       end
 
+      protected
+
+      # Return the maximum number of workers to autoscale the job to.
+      #
+      # While the number of active Kubernetes Jobs is less than this number,
+      # the gem will add new Jobs to auto-scale the workers.
+      #
+      # By default, this returns `Resque::Kubernetes.max_workers` from the gem
+      # configuration. You may override this method to return any other value,
+      # either as a simple integer or with some complex logic.
+      #
+      # Example:
+      #    def max_workers
+      #      # A simple integer
+      #      105
+      #    end
+      #
+      # Example:
+      #    def max_workers
+      #      # Scale based on time of day
+      #      Time.now.hour < 8 ? 15 : 5
+      #    end
+      def max_workers
+        Resque::Kubernetes.max_workers
+      end
+
       private
 
       def jobs_client
@@ -98,7 +124,7 @@ def jobs_maxed?(name, namespace)
             namespace:      namespace
         )
         running = resque_jobs.reject { |job| job.spec.completions == job.status.succeeded }
-        running.size == Resque::Kubernetes.max_workers
+        running.size == max_workers
       end
 
       def adjust_manifest(manifest)