diff --git a/vendor/github.com/json-iterator/go/iter_object.go b/vendor/github.com/json-iterator/go/iter_object.go
new file mode 100644
index 0000000..1c57576
--- /dev/null
+++ b/vendor/github.com/json-iterator/go/iter_object.go
@@ -0,0 +1,251 @@
+package jsoniter
+
+import (
+	"fmt"
+	"strings"
+)
+
+// ReadObject read one field from object.
+// If object ended, returns empty string.
+// Otherwise, returns the field name.
+func (iter *Iterator) ReadObject() (ret string) {
+	c := iter.nextToken()
+	switch c {
+	case 'n':
+		iter.skipThreeBytes('u', 'l', 'l')
+		return "" // null
+	case '{':
+		c = iter.nextToken()
+		if c == '"' {
+			iter.unreadByte()
+			field := iter.ReadString()
+			c = iter.nextToken()
+			if c != ':' {
+				iter.ReportError("ReadObject", "expect : after object field, but found "+string([]byte{c}))
+			}
+			return field
+		}
+		if c == '}' {
+			return "" // end of object
+		}
+		iter.ReportError("ReadObject", `expect " after {, but found `+string([]byte{c}))
+		return
+	case ',':
+		field := iter.ReadString()
+		c = iter.nextToken()
+		if c != ':' {
+			iter.ReportError("ReadObject", "expect : after object field, but found "+string([]byte{c}))
+		}
+		return field
+	case '}':
+		return "" // end of object
+	default:
+		iter.ReportError("ReadObject", fmt.Sprintf(`expect { or , or } or n, but found %s`, string([]byte{c})))
+		return
+	}
+}
+
+// CaseInsensitive
+func (iter *Iterator) readFieldHash() int64 {
+	hash := int64(0x811c9dc5)
+	c := iter.nextToken()
+	if c != '"' {
+		iter.ReportError("readFieldHash", `expect ", but found `+string([]byte{c}))
+		return 0
+	}
+	for {
+		for i := iter.head; i < iter.tail; i++ {
+			// require ascii string and no escape
+			b := iter.buf[i]
+			if b == '\\' {
+				iter.head = i
+				for _, b := range iter.readStringSlowPath() {
+					if 'A' <= b && b <= 'Z' && !iter.cfg.caseSensitive {
+						b += 'a' - 'A'
+					}
+					hash ^= int64(b)
+					hash *= 0x1000193
+				}
+				c = iter.nextToken()
+				if c != ':' {
+					iter.ReportError("readFieldHash", `expect :, but found `+string([]byte{c}))
+					return 0
+				}
+				return hash
+			}
+			if b == '"' {
+				iter.head = i + 1
+				c = iter.nextToken()
+				if c != ':' {
+					iter.ReportError("readFieldHash", `expect :, but found `+string([]byte{c}))
+					return 0
+				}
+				return hash
+			}
+			if 'A' <= b && b <= 'Z' && !iter.cfg.caseSensitive {
+				b += 'a' - 'A'
+			}
+			hash ^= int64(b)
+			hash *= 0x1000193
+		}
+		if !iter.loadMore() {
+			iter.ReportError("readFieldHash", `incomplete field name`)
+			return 0
+		}
+	}
+}
+
+func calcHash(str string, caseSensitive bool) int64 {
+	if !caseSensitive {
+		str = strings.ToLower(str)
+	}
+	hash := int64(0x811c9dc5)
+	for _, b := range []byte(str) {
+		hash ^= int64(b)
+		hash *= 0x1000193
+	}
+	return int64(hash)
+}
+
+// ReadObjectCB read object with callback, the key is ascii only and field name not copied
+func (iter *Iterator) ReadObjectCB(callback func(*Iterator, string) bool) bool {
+	c := iter.nextToken()
+	var field string
+	if c == '{' {
+		c = iter.nextToken()
+		if c == '"' {
+			iter.unreadByte()
+			field = iter.ReadString()
+			c = iter.nextToken()
+			if c != ':' {
+				iter.ReportError("ReadObject", "expect : after object field, but found "+string([]byte{c}))
+			}
+			if !callback(iter, field) {
+				return false
+			}
+			c = iter.nextToken()
+			for c == ',' {
+				field = iter.ReadString()
+				c = iter.nextToken()
+				if c != ':' {
+					iter.ReportError("ReadObject", "expect : after object field, but found "+string([]byte{c}))
+				}
+				if !callback(iter, field) {
+					return false
+				}
+				c = iter.nextToken()
+			}
+			if c != '}' {
+				iter.ReportError("ReadObjectCB", `object not ended with }`)
+				return false
+			}
+			return true
+		}
+		if c == '}' {
+			return true
+		}
+		iter.ReportError("ReadObjectCB", `expect " after }, but found `+string([]byte{c}))
+		return false
+	}
+	if c == 'n' {
+		iter.skipThreeBytes('u', 'l', 'l')
+		return true // null
+	}
+	iter.ReportError("ReadObjectCB", `expect { or n, but found `+string([]byte{c}))
+	return false
+}
+
+// ReadMapCB read map with callback, the key can be any string
+func (iter *Iterator) ReadMapCB(callback func(*Iterator, string) bool) bool {
+	c := iter.nextToken()
+	if c == '{' {
+		c = iter.nextToken()
+		if c == '"' {
+			iter.unreadByte()
+			field := iter.ReadString()
+			if iter.nextToken() != ':' {
+				iter.ReportError("ReadMapCB", "expect : after object field, but found "+string([]byte{c}))
+				return false
+			}
+			if !callback(iter, field) {
+				return false
+			}
+			c = iter.nextToken()
+			for c == ',' {
+				field = iter.ReadString()
+				if iter.nextToken() != ':' {
+					iter.ReportError("ReadMapCB", "expect : after object field, but found "+string([]byte{c}))
+					return false
+				}
+				if !callback(iter, field) {
+					return false
+				}
+				c = iter.nextToken()
+			}
+			if c != '}' {
+				iter.ReportError("ReadMapCB", `object not ended with }`)
+				return false
+			}
+			return true
+		}
+		if c == '}' {
+			return true
+		}
+		iter.ReportError("ReadMapCB", `expect " after }, but found `+string([]byte{c}))
+		return false
+	}
+	if c == 'n' {
+		iter.skipThreeBytes('u', 'l', 'l')
+		return true // null
+	}
+	iter.ReportError("ReadMapCB", `expect { or n, but found `+string([]byte{c}))
+	return false
+}
+
+func (iter *Iterator) readObjectStart() bool {
+	c := iter.nextToken()
+	if c == '{' {
+		c = iter.nextToken()
+		if c == '}' {
+			return false
+		}
+		iter.unreadByte()
+		return true
+	} else if c == 'n' {
+		iter.skipThreeBytes('u', 'l', 'l')
+		return false
+	}
+	iter.ReportError("readObjectStart", "expect { or n, but found "+string([]byte{c}))
+	return false
+}
+
+func (iter *Iterator) readObjectFieldAsBytes() (ret []byte) {
+	str := iter.ReadStringAsSlice()
+	if iter.skipWhitespacesWithoutLoadMore() {
+		if ret == nil {
+			ret = make([]byte, len(str))
+			copy(ret, str)
+		}
+		if !iter.loadMore() {
+			return
+		}
+	}
+	if iter.buf[iter.head] != ':' {
+		iter.ReportError("readObjectFieldAsBytes", "expect : after object field, but found "+string([]byte{iter.buf[iter.head]}))
+		return
+	}
+	iter.head++
+	if iter.skipWhitespacesWithoutLoadMore() {
+		if ret == nil {
+			ret = make([]byte, len(str))
+			copy(ret, str)
+		}
+		if !iter.loadMore() {
+			return
+		}
+	}
+	if ret == nil {
+		return str
+	}
+	return ret
+}