Extract flatjson package

stats/stats.go

@@ -10,6 +10,7 @@ import (
 	"time"
 
 	"github.com/chihaya/chihaya/config"
+	"github.com/pushrax/flatjson"
 )
 
 const (
@@ -93,7 +94,7 @@ type Stats struct {
 	responseTimeEvents chan time.Duration
 	recordMemStats     <-chan time.Time
 
-	flattened FlatMap
+	flattened flatjson.FlatMap
 }
 
 func New(cfg config.StatsConfig) *Stats {
@@ -117,12 +118,12 @@ func New(cfg config.StatsConfig) *Stats {
 		s.recordMemStats = time.NewTicker(cfg.MemUpdateInterval.Duration).C
 	}
 
-	s.flattened = Flatten(s)
+	s.flattened = flatjson.Flatten(s)
 	go s.handleEvents()
 	return s
 }
 
-func (s *Stats) Flattened() FlatMap {
+func (s *Stats) Flattened() flatjson.FlatMap {
 	return s.flattened
 }
 

stats/struct_flattener.go

@@ -1,101 +0,0 @@
-package stats
-
-import (
-	"reflect"
-	"strings"
-)
-
-type FlatMap map[string]interface{}
-
-func isEmptyValue(v reflect.Value) bool {
-	return v.Interface() == reflect.Zero(v.Type()).Interface()
-}
-
-func keyForField(field reflect.StructField, v reflect.Value) (string, bool) {
-	if tag := field.Tag.Get("json"); tag != "" {
-		tokens := strings.SplitN(tag, ",", 2)
-		name := tokens[0]
-		opts := ""
-
-		if len(tokens) > 1 {
-			opts = tokens[1]
-		}
-
-		if name == "-" || strings.Contains(opts, "omitempty") && isEmptyValue(v) {
-			return "", false
-		} else if name != "" {
-			return name, false
-		}
-	}
-
-	if field.Anonymous {
-		return "", true
-	}
-	return field.Name, false
-}
-
-func extractValue(val, fallback reflect.Value) reflect.Value {
-	switch val.Kind() {
-	case reflect.Struct:
-		return val
-	case reflect.Ptr:
-		return extractValue(val.Elem(), fallback)
-	case reflect.Interface:
-		return extractValue(val.Elem(), fallback)
-	default:
-		return fallback
-	}
-}
-
-func recursiveFlatten(val reflect.Value, prefix string, output FlatMap) int {
-	valType := val.Type()
-	added := 0
-
-	for i := 0; i < val.NumField(); i++ {
-		child := val.Field(i)
-		childType := valType.Field(i)
-		childPrefix := ""
-
-		key, anonymous := keyForField(childType, child)
-
-		if childType.PkgPath != "" || (key == "" && !anonymous) {
-			continue
-		}
-
-		child = extractValue(child, child)
-		if !anonymous {
-			childPrefix = prefix + key + "."
-		}
-
-		if child.Kind() == reflect.Struct {
-			childAdded := recursiveFlatten(child, childPrefix, output)
-			if childAdded != 0 {
-				added += childAdded
-				continue
-			}
-		}
-
-		output[prefix+key] = child.Addr().Interface()
-		added++
-	}
-
-	return added
-}
-
-func flattenValue(val reflect.Value) FlatMap {
-	if val.Kind() == reflect.Ptr {
-		return flattenValue(val.Elem())
-	}
-
-	if val.Kind() != reflect.Struct {
-		panic("must be called with a struct type")
-	}
-
-	m := FlatMap{}
-	recursiveFlatten(val, "", m)
-	return m
-}
-
-func Flatten(val interface{}) FlatMap {
-	return flattenValue(reflect.ValueOf(val))
-}