Merge pull request #17354 from NickLaMuro/sql_improvements_for_miq_re…

…quest_workflow

Prevents N+1 SQL queries in miq_request_workflow.rb

app/models/host.rb

@@ -1750,11 +1750,19 @@ def openstack_host? # TODO: This doesn't belong here
   end
 
   def writable_storages
-    storages.where(:host_storages => {:read_only => [false, nil]})
+    if host_storages.loaded? && host_storages.all? { |hs| hs.association(:storage).loaded? }
+      host_storages.reject(&:read_only).map(&:storage)
+    else
+      storages.where(:host_storages => {:read_only => [false, nil]})
+    end
   end
 
   def read_only_storages
-    storages.where(:host_storages => {:read_only => true})
+    if host_storages.loaded? && host_storages.all? { |hs| hs.association(:storage).loaded? }
+      host_storages.select(&:read_only).map(&:storage)
+    else
+      storages.where(:host_storages => {:read_only => true})
+    end
   end
 
   def archived?

app/models/miq_provision_virt_workflow.rb

@@ -1077,7 +1077,9 @@ def get_selected_hosts(src)
             elsif src[:host_id]
               selected_host(src)
             else
-              load_ar_obj(allowed_hosts)
+              allowed_hosts.group_by(&:evm_object_class).flat_map do |type, objs|
+                type.to_s.camelize.constantize.where(:id => objs.map(&:id)).to_a
+              end
             end
     Rbac.filtered(hosts, :class => Host, :user => @requester)
   end

app/models/miq_request_workflow.rb

@@ -1055,7 +1055,7 @@ def allowed_storages(_options = {})
 
     rails_logger('allowed_storages', 0)
     st = Time.now
-    MiqPreloader.preload(hosts, :storages)
+    MiqPreloader.preload(hosts, :storages => {}, :host_storages => :storage)
 
     storages = hosts.each_with_object({}) do |host, hash|
       host.writable_storages.each { |s| hash[s.id] = s }