Added support for API slugs

app/models/application_record.rb

@@ -6,6 +6,7 @@ class ApplicationRecord < ActiveRecord::Base
   include ArRegion
   include ArLock
   include ArNestedCountBy
+  include ArHrefSlug
   include ToModelHash
 
   extend ArTableLock

lib/api/collection_config.rb

@@ -73,6 +73,13 @@ def name_for_klass(resource_klass)
       @cfg.detect { |_, spec| spec[:klass] == resource_klass.name }.try(:first)
     end
 
+    def name_for_subclass(resource_class)
+      @cfg.detect do |collection, _|
+        collection_class = klass(collection)
+        collection_class && (collection_class == resource_class || collection_class.descendants.include?(resource_class))
+      end.try(:first)
+    end
+
     def what_refers_to_feature(product_feature_name)
       referenced_identifiers[product_feature_name]
     end

lib/api/utils.rb

@@ -0,0 +1,9 @@
+module Api
+  module Utils
+    def self.build_href_slug(klass, id)
+      return unless id
+      collection = Api::CollectionConfig.new.name_for_subclass(klass)
+      "#{collection}/#{id}" if collection
+    end
+  end
+end

lib/extensions/ar_href_slug.rb

@@ -0,0 +1,11 @@
+module ArHrefSlug
+  extend ActiveSupport::Concern
+
+  included do
+    virtual_column :href_slug, :type => :string
+
+    def href_slug
+      Api::Utils.build_href_slug(self.class, id)
+    end
+  end
+end

spec/lib/api/collection_config_spec.rb

@@ -8,4 +8,18 @@
       expect(subject.name_for_klass(String)).to be_nil
     end
   end
+
+  describe "#name_for_subclass" do
+    it "returns the collection name for classes declared by the API" do
+      expect(subject.name_for_subclass(Vm)).to eq(:vms)
+    end
+
+    it "returns the collection name for classes that are accessible via collection_class" do
+      expect(subject.name_for_subclass(ManageIQ::Providers::Vmware::InfraManager::Vm)).to eq(:vms)
+    end
+
+    it "returns nil for classes unknown to the API" do
+      expect(subject.name_for_subclass(String)).to be_nil
+    end
+  end
 end

spec/requests/api/querying_spec.rb

@@ -506,18 +506,19 @@ def create_vms_by_name(names)
       api_basic_authorize collection_action_identifier(:vms, :read, :get)
       vm = create_vms_by_name(%w(aa)).first
 
-      run_get vms_url, :expand => "resources", :attributes => "name,vendor"
+      run_get vms_url, :expand => "resources", :attributes => "href_slug,name,vendor"
 
       expected = {
         "name"      => "vms",
         "count"     => 1,
         "subcount"  => 1,
         "resources" => [
           {
-            "id"     => vm.id,
-            "href"   => a_string_matching(vms_url(vm.id)),
-            "name"   => "aa",
-            "vendor" => anything
+            "id"        => vm.id,
+            "href"      => a_string_matching(vms_url(vm.id)),
+            "href_slug" => "vms/#{vm.id}",
+            "name"      => "aa",
+            "vendor"    => anything
           }
         ]
       }