Ensure default values exist for worker limits/requests

Skip validation of limits/request unless one is specified: mostly for testing.
If you specify one of them for a worker, all four need to be specified or
inherited from ancestor worker classes.

lib/vmdb/settings/validator.rb

@@ -186,13 +186,27 @@ def workers(data)
       def validate_worker_request_limit(worker_class, data)
         valid = true
         errors = []
-        worker_settings = worker_class.worker_settings(data)
+        worker_settings = worker_class.fetch_worker_settings_from_options_hash(data[:config])
+
+        # Only validate request/limits if you specify any of them.  Specifying at least one of these four, requires
+        # all of them to be enumerated. This gets around tests that want to stub some of the worker_settings.
+        worker_settings_keys_with_dependencies = %i[cpu_request_percent cpu_threshold_percent memory_request memory_threshold]
+        return valid, errors if (worker_settings.keys & worker_settings_keys_with_dependencies).empty?
+
+        worker_settings_keys_with_dependencies.each do |key|
+          if !worker_settings.key?(key)
+            errors << [key, "#{worker_class.settings_name} #{key} is missing!"]
+            return false, errors
+          elsif !worker_settings[key].kind_of?(Numeric)
+            errors << [key, "#{worker_class.settings_name} #{key} has non-numeric value: #{worker_settings[key].inspect}"]
+            return false, errors
+          end
+        end
 
-        # add assertions that these keys exist - remove defaults
-        cpu_request     = worker_settings[:cpu_request_percent] || 0
-        cpu_limit       = worker_settings[:cpu_threshold_percent] || Float::INFINITY
-        memory_request  = worker_settings[:memory_request] || 0.bytes
-        memory_limit    = worker_settings[:memory_threshold] || Float::INFINITY.megabytes
+        cpu_request     = worker_settings[:cpu_request_percent]
+        cpu_limit       = worker_settings[:cpu_threshold_percent]
+        memory_request  = worker_settings[:memory_request]
+        memory_limit    = worker_settings[:memory_threshold]
 
         if cpu_request > cpu_limit
           valid = false

spec/lib/vmdb/settings/validator_spec.rb

@@ -111,13 +111,29 @@
       expect(errors.first.last).to include("cannot exceed cpu_threshold_percent")
     end
 
-    [:memory_request, 500.megabytes, :memory_threshold, 500.megabytes, :cpu_request, 50, :cpu_threshold_percent, 50].each_slice(2) do |key, value|
-      it "is valid with nil values replaced with default values, when specifying only: #{key}" do
-        stub_settings_merge(:workers => {:worker_base => {:defaults => {:cpu_request_percent => nil, :cpu_threshold_percent => nil}, :schedule_worker => {key => value}}})
-        result, errors = subject.validate
-        expect(result).to eql(true)
-        expect(errors.empty?).to eql(true)
-      end
+    it "is invalid if one of the request/limit values is nil" do
+      stub_settings_merge(:workers => {:worker_base => {:defaults => {:cpu_request_percent => nil}}})
+      result, errors = subject.validate
+      expect(result).to eql(false)
+      expect(errors.first.first).to eql("workers-cpu_request_percent")
+      expect(errors.first.last).to include("has non-numeric value")
+    end
+
+    it "is invalid if one of the request/limit values is provided but one is missing" do
+      hash = Settings.to_hash
+      hash[:workers][:worker_base][:defaults].delete(:cpu_threshold_percent)
+      stub_settings(hash)
+      result, errors = subject.validate
+      expect(result).to eql(false)
+      expect(errors.first.first).to eql("workers-cpu_threshold_percent")
+      expect(errors.first.last).to include("is missing")
+    end
+
+    it "is valid if none of the request/limit values are provided" do
+      stub_settings({})
+      result, errors = subject.validate
+      expect(result).to eql(true)
+      expect(errors.empty?).to eql(true)
     end
   end
 end