Fix Reference (#1095)

Make sure that reference type attributes have been computed
prior to building base attribute that relies on it.

design/apidsl/attribute.go

@@ -110,13 +110,7 @@ func Attribute(name string, args ...interface{}) {
 			return
 		}
 
-		var baseAttr *design.AttributeDefinition
-		if parent.Reference != nil && parent.Reference.IsObject() {
-			if att, ok := parent.Reference.ToObject()[name]; ok {
-				baseAttr = design.DupAtt(att)
-			}
-		}
-
+		baseAttr := attributeFromRef(name, parent.Reference)
 		dataType, description, dsl := parseAttributeArgs(baseAttr, args...)
 		if baseAttr != nil {
 			if description != "" {
@@ -143,6 +137,35 @@ func Attribute(name string, args ...interface{}) {
 	}
 }
 
+// attributeFromRef returns a base attribute given a reference data type.
+// It takes care of running the DSL on the reference type if it hasn't run yet.
+func attributeFromRef(name string, ref design.DataType) *design.AttributeDefinition {
+	if ref == nil {
+		return nil
+	}
+	switch t := ref.(type) {
+	case *design.UserTypeDefinition:
+		if t.DSLFunc != nil {
+			dsl := t.DSLFunc
+			t.DSLFunc = nil
+			dslengine.Execute(dsl, t.AttributeDefinition)
+		}
+		if att, ok := t.ToObject()[name]; ok {
+			return design.DupAtt(att)
+		}
+	case *design.MediaTypeDefinition:
+		if t.DSLFunc != nil {
+			dsl := t.DSLFunc
+			t.DSLFunc = nil
+			dslengine.Execute(dsl, t)
+		}
+		if att, ok := t.ToObject()[name]; ok {
+			return design.DupAtt(att)
+		}
+	}
+	return nil
+}
+
 func parseAttributeArgs(baseAttr *design.AttributeDefinition, args ...interface{}) (design.DataType, string, func()) {
 	var (
 		dataType    design.DataType

dslengine/runner.go

@@ -294,7 +294,9 @@ func runSet(set DefinitionSet) error {
 		for _, def := range set[executed:] {
 			executed++
 			if source, ok := def.(Source); ok {
-				Execute(source.DSL(), source)
+				if dsl := source.DSL(); dsl != nil {
+					Execute(dsl, source)
+				}
 			}
 		}
 		if recursed > 100 {