diff --git a/httplib/httplib.go b/httplib/httplib.go
index 935b7a71..2389a7cb 100644
--- a/httplib/httplib.go
+++ b/httplib/httplib.go
@@ -36,6 +36,7 @@ import (
 	"crypto/tls"
 	"encoding/json"
 	"encoding/xml"
+	"fmt"
 	"io"
 	"io/ioutil"
 	"log"
@@ -47,32 +48,20 @@ import (
 	"net/url"
 	"os"
 	"strings"
-	"sync"
 	"time"
 )
 
-var defaultSetting = BeegoHttpSettings{false, "beegoServer", 60 * time.Second, 60 * time.Second, nil, nil, nil, false, true}
+var defaultSetting = BeegoHttpSettings{UserAgent: "beegoServer", ConnectTimeout: 60 * time.Second, ReadWriteTimeout: 60 * time.Second, Gzip: true}
 var defaultCookieJar http.CookieJar
-var settingMutex sync.Mutex
 
 // createDefaultCookie creates a global cookiejar to store cookies.
 func createDefaultCookie() {
-	settingMutex.Lock()
-	defer settingMutex.Unlock()
 	defaultCookieJar, _ = cookiejar.New(nil)
 }
 
 // Overwrite default settings
 func SetDefaultSetting(setting BeegoHttpSettings) {
-	settingMutex.Lock()
-	defer settingMutex.Unlock()
 	defaultSetting = setting
-	if defaultSetting.ConnectTimeout == 0 {
-		defaultSetting.ConnectTimeout = 60 * time.Second
-	}
-	if defaultSetting.ReadWriteTimeout == 0 {
-		defaultSetting.ReadWriteTimeout = 60 * time.Second
-	}
 }
 
 // return *BeegoHttpRequest with specific method
@@ -85,7 +74,14 @@ func newBeegoRequest(url, method string) *BeegoHttpRequest {
 		ProtoMajor: 1,
 		ProtoMinor: 1,
 	}
-	return &BeegoHttpRequest{url, &req, map[string]string{}, map[string]string{}, defaultSetting, &resp, nil, nil}
+	return &BeegoHttpRequest{
+		url:     url,
+		req:     &req,
+		params:  map[string]string{},
+		files:   map[string]string{},
+		setting: defaultSetting,
+		resp:    &resp,
+	}
 }
 
 // Get returns *BeegoHttpRequest with GET method.
@@ -157,14 +153,14 @@ func (b *BeegoHttpRequest) SetEnableCookie(enable bool) *BeegoHttpRequest {
 }
 
 // SetUserAgent sets User-Agent header field
-func (b *BeegoHttpRequest) SetUserAgent(useragent string) *BeegoHttpRequest {
-	b.setting.UserAgent = useragent
+func (b *BeegoHttpRequest) SetUserAgent(userAgent string) *BeegoHttpRequest {
+	b.setting.UserAgent = userAgent
 	return b
 }
 
 // Debug sets show debug or not when executing request.
-func (b *BeegoHttpRequest) Debug(isdebug bool) *BeegoHttpRequest {
-	b.setting.ShowDebug = isdebug
+func (b *BeegoHttpRequest) Debug(isDebug bool) *BeegoHttpRequest {
+	b.setting.ShowDebug = isDebug
 	return b
 }
 
@@ -283,12 +279,15 @@ func (b *BeegoHttpRequest) JsonBody(obj interface{}) (*BeegoHttpRequest, error)
 }
 
 func (b *BeegoHttpRequest) buildUrl(paramBody string) {
+	if paramBody == "" {
+		return
+	}
 	// build GET url with query string
-	if b.req.Method == "GET" && len(paramBody) > 0 {
-		if strings.Index(b.url, "?") != -1 {
-			b.url += "&" + paramBody
-		} else {
+	if b.req.Method == "GET" {
+		if strings.Index(b.url, "?") == -1 {
 			b.url = b.url + "?" + paramBody
+		} else {
+			b.url += "&" + paramBody
 		}
 		return
 	}
@@ -341,18 +340,14 @@ func (b *BeegoHttpRequest) getResponse() (*http.Response, error) {
 	}
 	var paramBody string
 	if len(b.params) > 0 {
-		var buf bytes.Buffer
 		for k, v := range b.params {
-			buf.WriteString(url.QueryEscape(k))
-			buf.WriteByte('=')
-			buf.WriteString(url.QueryEscape(v))
-			buf.WriteByte('&')
+			paramBody += fmt.Sprintf("&%s=%v", url.QueryEscape(k), url.QueryEscape(v))
 		}
-		paramBody = buf.String()
-		paramBody = paramBody[0 : len(paramBody)-1]
+		paramBody = paramBody[1:]
 	}
 
 	b.buildUrl(paramBody)
+
 	url, err := url.Parse(b.url)
 	if err != nil {
 		return nil, err
@@ -362,6 +357,13 @@ func (b *BeegoHttpRequest) getResponse() (*http.Response, error) {
 
 	trans := b.setting.Transport
 
+	if b.setting.ConnectTimeout == 0 {
+		b.setting.ConnectTimeout = 60 * time.Second
+	}
+	if b.setting.ReadWriteTimeout == 0 {
+		b.setting.ReadWriteTimeout = 60 * time.Second
+	}
+
 	if trans == nil {
 		// create default transport
 		trans = &http.Transport{
@@ -404,17 +406,13 @@ func (b *BeegoHttpRequest) getResponse() (*http.Response, error) {
 	if b.setting.ShowDebug {
 		dump, err := httputil.DumpRequest(b.req, true)
 		if err != nil {
-			println(err.Error())
+			log.Println(err.Error())
 		}
 		b.dump = dump
 	}
 
-	resp, err := client.Do(b.req)
-	if err != nil {
-		return nil, err
-	}
-	b.resp = resp
-	return resp, nil
+	b.resp, err = client.Do(b.req)
+	return b.resp, err
 }
 
 // String returns the body string in response.
@@ -435,12 +433,9 @@ func (b *BeegoHttpRequest) Bytes() ([]byte, error) {
 		return b.body, nil
 	}
 	resp, err := b.getResponse()
-	if err != nil {
+	if resp == nil || resp.Body == nil {
 		return nil, err
 	}
-	if resp.Body == nil {
-		return nil, nil
-	}
 	defer resp.Body.Close()
 	if b.setting.Gzip && resp.Header.Get("Content-Encoding") == "gzip" {
 		reader, err := gzip.NewReader(resp.Body)
@@ -451,29 +446,24 @@ func (b *BeegoHttpRequest) Bytes() ([]byte, error) {
 	} else {
 		b.body, err = ioutil.ReadAll(resp.Body)
 	}
-	if err != nil {
-		return nil, err
-	}
-	return b.body, nil
+	return b.body, err
 }
 
 // ToFile saves the body data in response to one file.
 // it calls Response inner.
 func (b *BeegoHttpRequest) ToFile(filename string) error {
+	resp, err := b.getResponse()
+	if resp == nil || resp.Body == nil {
+		return err
+	}
+	defer resp.Body.Close()
+
 	f, err := os.Create(filename)
 	if err != nil {
 		return err
 	}
 	defer f.Close()
 
-	resp, err := b.getResponse()
-	if err != nil {
-		return err
-	}
-	if resp.Body == nil {
-		return nil
-	}
-	defer resp.Body.Close()
 	_, err = io.Copy(f, resp.Body)
 	return err
 }
@@ -510,7 +500,7 @@ func TimeoutDialer(cTimeout time.Duration, rwTimeout time.Duration) func(net, ad
 		if err != nil {
 			return nil, err
 		}
-		conn.SetDeadline(time.Now().Add(rwTimeout))
-		return conn, nil
+		err = conn.SetDeadline(time.Now().Add(rwTimeout))
+		return conn, err
 	}
 }