chore: Move private packages to internal (#1664)

internal/config/flatten.go

@@ -0,0 +1,73 @@
+package config
+
+import (
+	"fmt"
+	"strconv"
+)
+
+// flatten flattens the nested struct.
+//
+// All keys will be joined by dot
+// e.g. {"a": {"b":"c"}} => {"a.b":"c"}
+// or {"a": {"b":[1,2]}} => {"a.b.0":1, "a.b.1": 2}.
+func flatten(data map[string]interface{}) map[string]string {
+	ret := make(map[string]string)
+
+	for k, v := range data {
+		switch typed := v.(type) {
+		case map[interface{}]interface{}:
+			for fk, fv := range flatten(convertMap(typed)) {
+				ret[fmt.Sprintf("%s.%s", k, fk)] = fv
+			}
+		case map[string]interface{}:
+			for fk, fv := range flatten(typed) {
+				ret[fmt.Sprintf("%s.%s", k, fk)] = fv
+			}
+		case []interface{}:
+			for fk, fv := range flattenSlice(typed) {
+				ret[fmt.Sprintf("%s.%s", k, fk)] = fv
+			}
+		default:
+			ret[k] = fmt.Sprint(typed)
+		}
+	}
+
+	return ret
+}
+
+func flattenSlice(data []interface{}) map[string]string {
+	ret := make(map[string]string)
+
+	for idx, v := range data {
+		switch typed := v.(type) {
+		case map[interface{}]interface{}:
+			for fk, fv := range flatten(convertMap(typed)) {
+				ret[fmt.Sprintf("%d,%s", idx, fk)] = fv
+			}
+		case map[string]interface{}:
+			for fk, fv := range flatten(typed) {
+				ret[fmt.Sprintf("%d,%s", idx, fk)] = fv
+			}
+		case []interface{}:
+			for fk, fv := range flattenSlice(typed) {
+				ret[fmt.Sprintf("%d,%s", idx, fk)] = fv
+			}
+		default:
+			ret[strconv.Itoa(idx)] = fmt.Sprint(typed)
+		}
+	}
+
+	return ret
+}
+
+func convertMap(originalMap map[interface{}]interface{}) map[string]interface{} {
+	convertedMap := map[string]interface{}{}
+
+	for key, value := range originalMap {
+		if keyString, ok := key.(string); ok {
+			convertedMap[keyString] = value
+		}
+	}
+
+	return convertedMap
+}