Allow circular types to be imported

types/reflection.go

@@ -83,6 +83,9 @@ func (s *Schemas) newSchemaFromType(version *APIVersion, t reflect.Type, typeNam
 		CollectionActions: map[string]Action{},
 	}
 
+	s.processingTypes[t] = schema
+	defer delete(s.processingTypes, t)
+
 	if err := s.readFields(schema, t); err != nil {
 		return nil, err
 	}
@@ -148,6 +151,11 @@ func (s *Schemas) importType(version *APIVersion, t reflect.Type, overrides ...r
 		return existing, nil
 	}
 
+	if s, ok := s.processingTypes[t]; ok {
+		logrus.Debugf("Returning half built schema %s for %v", typeName, t)
+		return s, nil
+	}
+
 	logrus.Debugf("Inspecting schema %s for %v", typeName, t)
 
 	schema, err := s.newSchemaFromType(version, t, typeName)

types/schemas.go

@@ -29,6 +29,7 @@ type BackReference struct {
 
 type Schemas struct {
 	sync.Mutex
+	processingTypes    map[reflect.Type]*Schema
 	typeNames          map[reflect.Type]string
 	schemasByPath      map[string]map[string]*Schema
 	mappers            map[string]map[string][]Mapper
@@ -44,11 +45,12 @@ type Schemas struct {
 
 func NewSchemas() *Schemas {
 	return &Schemas{
-		typeNames:     map[reflect.Type]string{},
-		schemasByPath: map[string]map[string]*Schema{},
-		mappers:       map[string]map[string][]Mapper{},
-		references:    map[string][]BackReference{},
-		embedded:      map[string]*Schema{},
+		processingTypes: map[reflect.Type]*Schema{},
+		typeNames:       map[reflect.Type]string{},
+		schemasByPath:   map[string]map[string]*Schema{},
+		mappers:         map[string]map[string][]Mapper{},
+		references:      map[string][]BackReference{},
+		embedded:        map[string]*Schema{},
 	}
 }