Store next naming sequence in custom_attributes

With this implemenation naming sequences are global through current region.
The binding can be changed to other models through NamingSequenceMixin.

https://bugzilla.redhat.com/show_bug.cgi?id=1173336

vmdb/app/models/miq_provision/naming.rb

@@ -3,6 +3,7 @@ module MiqProvision::Naming
 
   NAME_VIA_AUTOMATE = true
   NAME_SEQUENCE_REGEX = /\$n\{(\d+)\}/
+  SOURCE_IDENTIFIER = "provisioning"  # a unique name for the source column in custom_attributes table
 
   module ClassMethods
     def get_next_vm_name(prov_obj, determine_index=true)
@@ -51,28 +52,20 @@ def get_vm_full_name(unresolved_vm_name, prov_obj, determine_index)
       # if we are just building a sample of what the vm_name will look like use '#' inplace of actual number.
       return "#{name[:prefix]}#{'#' * name[:index_length]}#{name[:suffix]}" if determine_index == false
 
-      # Determine starting index based on already assigned names in miq_provision table.
-      start_idx = 0
-      reg_val = Regexp.new("(#{name[:prefix]})(\\d{#{name[:index_length]}})(#{name[:suffix]})")
-
-      MiqProvision.find(:all).each do |p|
-        if p.options[:vm_target_name].to_s.strip =~ reg_val
-          name_prefix, name_idx, name_suffix = $1.to_s, $2.to_i, $3
-          # If the name prefix and suffix match record the highest index number
-          if name[:prefix].downcase == name_prefix.downcase && name[:suffix].to_s.downcase == name_suffix.to_s.downcase
-            start_idx = name_idx if name_idx > start_idx
-          end
+      index_length = name[:index_length]
+      loop do
+        next_number = MiqRegion.my_region.next_naming_sequence(unresolved_vm_name, SOURCE_IDENTIFIER)
+        idx_str  = "%0#{index_length}d" % next_number
+        if idx_str.length > index_length
+          index_length += 1
+          unresolved_vm_name = "#{name[:prefix]}$n{#{index_length}}#{name[:suffix]}"
+          next
         end
-      end
-      start_idx += 1
 
-      start_idx.upto(9999) do |x|
-        idx_str  = format("%0#{name[:index_length]}d", x)
         fullname = "#{name[:prefix]}#{idx_str}#{name[:suffix]}"
         vm       = check_vm_name_uniqueness(fullname, prov_obj)
         return fullname if vm.nil?
       end
-      return nil
     end
 
     def check_vm_name_uniqueness(fullname, prov_obj)
@@ -86,7 +79,4 @@ def check_vm_name_uniqueness(fullname, prov_obj)
   def get_next_vm_name()
     self.class.get_next_vm_name(self)
   end
-
-
-
 end

vmdb/app/models/miq_region.rb

@@ -19,7 +19,7 @@ class MiqRegion < ActiveRecord::Base
   acts_as_miq_taggable
   include ReportableMixin
   include UuidMixin
-
+  include NamingSequenceMixin
   include AggregationMixin
   # Since we've overridden the implementation of methods from AggregationMixin,
   # we must also override the :uses portion of the virtual columns.

vmdb/app/models/mixins/naming_sequence_mixin.rb

@@ -0,0 +1,17 @@
+module NamingSequenceMixin
+  extend ActiveSupport::Concern
+
+  included do
+    # these are possible naming sequences because there is no constraint to source column
+    has_many :naming_sequences, :as => :resource, :dependent => :destroy, :class_name => "CustomAttribute"
+  end
+
+  def next_naming_sequence(name, source)
+    lock do
+      record = naming_sequences.where(:name => name, :source => source).first_or_initialize
+      record.update_attributes!(:value => record.value.to_i + 1)
+
+      record.value
+    end
+  end
+end

vmdb/spec/models/miq_provision_spec.rb

@@ -76,6 +76,24 @@
           @vm_prov.get_option(:vm_target_hostname).should == name_002.gsub(/ +|_+/, "-")
         end
 
+        context "when auto naming sequence exceeds the range" do
+          before do
+            region = MiqRegion.my_region
+            region.naming_sequences.create(:name => "#{@target_vm_name}$n{3}", :source => "provisioning", :value => 998)
+            region.naming_sequences.create(:name => "#{@target_vm_name}$n{4}", :source => "provisioning", :value => 10)
+          end
+
+          it "should advance to next range but based on the existing sequence number for the new range" do
+            @vm_prov.options[:number_of_vms] = 2
+            @vm_prov.after_request_task_create
+            @vm_prov.get_option(:vm_target_name).should == "#{@target_vm_name}999"  # 3 digits
+
+            @vm_prov.options[:pass] = 2
+            @vm_prov.after_request_task_create
+            @vm_prov.get_option(:vm_target_name).should == "#{@target_vm_name}0011" # 4 digits
+          end
+        end
+
         it "should create a hostname with a valid length based on the OS" do
           # Hostname lengths by platform:
           #   Linux   : 63

vmdb/spec/models/miq_region_spec.rb

@@ -27,6 +27,13 @@ def write_region(number)
       MiqRegion.count.should == 1
     end
 
+    it "should increment naming sequence number after each call" do
+      MiqRegion.my_region.next_naming_sequence("namingtest$n{3}", "naming").should == 1
+      MiqRegion.my_region.next_naming_sequence("namingtest$n{3}", "naming").should == 2
+      MiqRegion.my_region.next_naming_sequence("anothertest$n{3}", "naming").should == 1
+      MiqRegion.my_region.next_naming_sequence("anothertest$n{3}", "naming").should == 2
+    end
+
     context "with cloud and infra EMSes" do
 
       before :each do