Add 'allocated cpu cores' chargeback rate detail to existing chargeba…

…ck rates

db/migrate/20171026103833_add_cores_allocated_rate_detail.rb

@@ -0,0 +1,27 @@
+class AddCoresAllocatedRateDetail < ActiveRecord::Migration[5.0]
+  def up
+    chargeable_field = ChargeableField.find_or_create(:metric      => "derived_vm_numvcpus_cores",
+                                                      :description => "Allocated CPU Cores",
+                                                      :group       => "cpu_cores",
+                                                      :source      => "allocated") if chargeable_field.nil?
+
+    rate_detail_template = ChargebackRateDetail.where(:description => "Allocated CPU Count").first
+    return if rate_detail_template.nil? # No rates that need this detail.
+    rate_detail_template = rate_detail_template.dup
+    rate_detail_template.chargeable_field = chargeable_field
+    rate_detail_template.description = "Allocated CPU Cores"
+    rate_detail_template.per_unit = "cpu core"
+    tier_template = {:start => 0, :finish => Float::INFINITY, :fixed_rate => 1.0, :variable_rate => 0.0}
+
+    # Add to cb rates that do not have the "Allocated CPU Cores" cb detail
+    ChargebackRate.where(:rate_type => "Compute").where.not(:id => ChargebackRateDetail.where(:description => "Allocated CPU Cores").select(:chargeback_rate_id)).each do |rate|
+      new_rate_detail = rate_detail_template.dup
+      new_rate_detail.chargeback_tiers << ChargebackTier.new(tier_template.slice(*ChargebackTier::FORM_ATTRIBUTES))
+      rate.chargeback_rate_details << new_rate_detail
+    end
+  end
+
+  def down
+    ChargebackRateDetail.where(:description => "Allocated CPU Cores").destroy_all
+  end
+end