diff --git a/README.md b/README.md
index 96a779d..baadcb6 100644
--- a/README.md
+++ b/README.md
@@ -53,7 +53,7 @@ and import this when you need:
 import "github.com/casdoor/casdoor-go-sdk/casdoorsdk"
 ```
 
-## Step2. Init Config
+## Step2. Init
 
 Initialization requires 6 parameters, which are all string type:
 
@@ -66,10 +66,18 @@ Initialization requires 6 parameters, which are all string type:
 | organizationName | Yes  | Application.organization                            |
 | applicationName  | Yes  | Application.applicationName                         |
 
+### You can either init the sdk with global config
 ```go
 func InitConfig(endpoint string, clientId string, clientSecret string, certificate string, organizationName string, applicationName string)
-```
 
+// Then call sdk functions like
+casdoorsdk.GetUsers()
+```
+### or create a custom Client with unique config
+```go
+client := casdoorsdk.NewClient(endpoint, clientId, clientSecret, certificate, organizationName, applicationName)
+client.GetUsers()
+```
 ## Step3. Get token and parse
 
 After casdoor verification passed, it will be redirected to your application with code and state, like `https://forum.casbin.com?code=xxx&state=yyyy`.
diff --git a/casdoorsdk/application.go b/casdoorsdk/application.go
index d9d8efd..907ca42 100644
--- a/casdoorsdk/application.go
+++ b/casdoorsdk/application.go
@@ -76,7 +76,7 @@ type Application struct {
 	FormBackgroundUrl    string   `xorm:"varchar(200)" json:"formBackgroundUrl"`
 }
 
-func AddApplication(application *Application) (bool, error) {
+func (c *Client) AddApplication(application *Application) (bool, error) {
 	if application.Owner == "" {
 		application.Owner = "admin"
 	}
@@ -85,7 +85,7 @@ func AddApplication(application *Application) (bool, error) {
 		return false, err
 	}
 
-	resp, err := DoPost("add-application", nil, postBytes, false, false)
+	resp, err := c.DoPost("add-application", nil, postBytes, false, false)
 	if err != nil {
 		return false, err
 	}
@@ -93,7 +93,11 @@ func AddApplication(application *Application) (bool, error) {
 	return resp.Data == "Affected", nil
 }
 
-func DeleteApplication(name string) (bool, error) {
+func AddApplication(application *Application) (bool, error) {
+	return globalClient.AddApplication(application)
+}
+
+func (c *Client) DeleteApplication(name string) (bool, error) {
 	application := Application{
 		Owner: "admin",
 		Name:  name,
@@ -103,10 +107,14 @@ func DeleteApplication(name string) (bool, error) {
 		return false, err
 	}
 
-	resp, err := DoPost("delete-application", nil, postBytes, false, false)
+	resp, err := c.DoPost("delete-application", nil, postBytes, false, false)
 	if err != nil {
 		return false, err
 	}
 
 	return resp.Data == "Affected", nil
 }
+
+func DeleteApplication(name string) (bool, error) {
+	return globalClient.DeleteApplication(name)
+}
diff --git a/casdoorsdk/auth.go b/casdoorsdk/auth.go
index 4cb576e..25a97dc 100644
--- a/casdoorsdk/auth.go
+++ b/casdoorsdk/auth.go
@@ -25,15 +25,30 @@ type AuthConfig struct {
 	ApplicationName  string
 }
 
-var authConfig AuthConfig
+type Client struct {
+	AuthConfig
+}
+
+var globalClient *Client
 
 func InitConfig(endpoint string, clientId string, clientSecret string, certificate string, organizationName string, applicationName string) {
-	authConfig = AuthConfig{
-		Endpoint:         endpoint,
-		ClientId:         clientId,
-		ClientSecret:     clientSecret,
-		Certificate:      certificate,
-		OrganizationName: organizationName,
-		ApplicationName:  applicationName,
+	globalClient = NewClient(endpoint, clientId, clientSecret, certificate, organizationName, applicationName)
+}
+
+func NewClient(endpoint string, clientId string, clientSecret string, certificate string, organizationName string, applicationName string) *Client {
+	return NewClientWithConf(
+		&AuthConfig{
+			Endpoint:         endpoint,
+			ClientId:         clientId,
+			ClientSecret:     clientSecret,
+			Certificate:      certificate,
+			OrganizationName: organizationName,
+			ApplicationName:  applicationName,
+		})
+}
+
+func NewClientWithConf(config *AuthConfig) *Client {
+	return &Client{
+		*config,
 	}
 }
diff --git a/casdoorsdk/base.go b/casdoorsdk/base.go
index 466d999..1449f4f 100644
--- a/casdoorsdk/base.go
+++ b/casdoorsdk/base.go
@@ -25,10 +25,8 @@ import (
 	"strings"
 )
 
-var (
-	// client is a shared http Client.
-	client HttpClient = &http.Client{}
-)
+// client is a shared http Client.
+var client HttpClient = &http.Client{}
 
 // SetHttpClient sets custom http Client.
 func SetHttpClient(httpClient HttpClient) {
@@ -49,8 +47,8 @@ type Response struct {
 }
 
 // DoGetResponse is a general function to get response from param url through HTTP Get method.
-func DoGetResponse(url string) (*Response, error) {
-	respBytes, err := doGetBytesRawWithoutCheck(url)
+func (c *Client) DoGetResponse(url string) (*Response, error) {
+	respBytes, err := c.doGetBytesRawWithoutCheck(url)
 	if err != nil {
 		return nil, err
 	}
@@ -69,8 +67,8 @@ func DoGetResponse(url string) (*Response, error) {
 }
 
 // DoGetBytes is a general function to get response data in bytes from param url through HTTP Get method.
-func DoGetBytes(url string) ([]byte, error) {
-	response, err := DoGetResponse(url)
+func (c *Client) DoGetBytes(url string) ([]byte, error) {
+	response, err := c.DoGetResponse(url)
 	if err != nil {
 		return nil, err
 	}
@@ -84,23 +82,23 @@ func DoGetBytes(url string) ([]byte, error) {
 }
 
 // DoGetBytesRaw is a general function to get response from param url through HTTP Get method.
-func DoGetBytesRaw(url string) ([]byte, error) {
-	respBytes, err := doGetBytesRawWithoutCheck(url)
+func (c *Client) DoGetBytesRaw(url string) ([]byte, error) {
+	respBytes, err := c.doGetBytesRawWithoutCheck(url)
 	if err != nil {
 		return nil, err
 	}
 
 	var response Response
 	err = json.Unmarshal(respBytes, &response)
-	if err == nil && response.Status == "error"{
+	if err == nil && response.Status == "error" {
 		return nil, errors.New(response.Msg)
 	}
 
 	return respBytes, nil
 }
 
-func DoPost(action string, queryMap map[string]string, postBytes []byte, isForm, isFile bool) (*Response, error) {
-	url := GetUrl(action, queryMap)
+func (c *Client) DoPost(action string, queryMap map[string]string, postBytes []byte, isForm, isFile bool) (*Response, error) {
+	url := c.GetUrl(action, queryMap)
 
 	var err error
 	var contentType string
@@ -128,7 +126,7 @@ func DoPost(action string, queryMap map[string]string, postBytes []byte, isForm,
 		body = bytes.NewReader(postBytes)
 	}
 
-	respBytes, err := DoPostBytesRaw(url, contentType, body)
+	respBytes, err := c.DoPostBytesRaw(url, contentType, body)
 	if err != nil {
 		return nil, err
 	}
@@ -147,7 +145,7 @@ func DoPost(action string, queryMap map[string]string, postBytes []byte, isForm,
 }
 
 // DoPostBytesRaw is a general function to post a request from url, body through HTTP Post method.
-func DoPostBytesRaw(url string, contentType string, body io.Reader) ([]byte, error) {
+func (c *Client) DoPostBytesRaw(url string, contentType string, body io.Reader) ([]byte, error) {
 	if contentType == "" {
 		contentType = "text/plain;charset=UTF-8"
 	}
@@ -159,7 +157,7 @@ func DoPostBytesRaw(url string, contentType string, body io.Reader) ([]byte, err
 		return nil, err
 	}
 
-	req.SetBasicAuth(authConfig.ClientId, authConfig.ClientSecret)
+	req.SetBasicAuth(c.ClientId, c.ClientSecret)
 	req.Header.Set("Content-Type", contentType)
 
 	resp, err = client.Do(req)
@@ -182,13 +180,13 @@ func DoPostBytesRaw(url string, contentType string, body io.Reader) ([]byte, err
 }
 
 // doGetBytesRawWithoutCheck is a general function to get response from param url through HTTP Get method without checking response status
-func doGetBytesRawWithoutCheck(url string) ([]byte, error) {
+func (c *Client) doGetBytesRawWithoutCheck(url string) ([]byte, error) {
 	req, err := http.NewRequest("GET", url, nil)
 	if err != nil {
 		return nil, err
 	}
 
-	req.SetBasicAuth(authConfig.ClientId, authConfig.ClientSecret)
+	req.SetBasicAuth(c.ClientId, c.ClientSecret)
 
 	resp, err := client.Do(req)
 	if err != nil {
@@ -211,11 +209,11 @@ func doGetBytesRawWithoutCheck(url string) ([]byte, error) {
 
 // modifyUser is an encapsulation of user CUD(Create, Update, Delete) operations.
 // possible actions are `add-user`, `update-user`, `delete-user`,
-func modifyUser(action string, user *User, columns []string) (*Response, bool, error) {
-	return modifyUserById(action, user.GetId(), user, columns)
+func (c *Client) modifyUser(action string, user *User, columns []string) (*Response, bool, error) {
+	return c.modifyUserById(action, user.GetId(), user, columns)
 }
 
-func modifyUserById(action string, id string, user *User, columns []string) (*Response, bool, error) {
+func (c *Client) modifyUserById(action string, id string, user *User, columns []string) (*Response, bool, error) {
 	queryMap := map[string]string{
 		"id": id,
 	}
@@ -224,13 +222,13 @@ func modifyUserById(action string, id string, user *User, columns []string) (*Re
 		queryMap["columns"] = strings.Join(columns, ",")
 	}
 
-	user.Owner = authConfig.OrganizationName
+	user.Owner = c.OrganizationName
 	postBytes, err := json.Marshal(user)
 	if err != nil {
 		return nil, false, err
 	}
 
-	resp, err := DoPost(action, queryMap, postBytes, false, false)
+	resp, err := c.DoPost(action, queryMap, postBytes, false, false)
 	if err != nil {
 		return nil, false, err
 	}
@@ -240,7 +238,7 @@ func modifyUserById(action string, id string, user *User, columns []string) (*Re
 
 // modifyPermission is an encapsulation of permission CUD(Create, Update, Delete) operations.
 // possible actions are `add-permission`, `update-permission`, `delete-permission`,
-func modifyPermission(action string, permission *Permission, columns []string) (*Response, bool, error) {
+func (c *Client) modifyPermission(action string, permission *Permission, columns []string) (*Response, bool, error) {
 	queryMap := map[string]string{
 		"id": fmt.Sprintf("%s/%s", permission.Owner, permission.Name),
 	}
@@ -249,13 +247,13 @@ func modifyPermission(action string, permission *Permission, columns []string) (
 		queryMap["columns"] = strings.Join(columns, ",")
 	}
 
-	permission.Owner = authConfig.OrganizationName
+	permission.Owner = c.OrganizationName
 	postBytes, err := json.Marshal(permission)
 	if err != nil {
 		return nil, false, err
 	}
 
-	resp, err := DoPost(action, queryMap, postBytes, false, false)
+	resp, err := c.DoPost(action, queryMap, postBytes, false, false)
 	if err != nil {
 		return nil, false, err
 	}
@@ -265,7 +263,7 @@ func modifyPermission(action string, permission *Permission, columns []string) (
 
 // modifyRole is an encapsulation of role CUD(Create, Update, Delete) operations.
 // possible actions are `add-role`, `update-role`, `delete-role`,
-func modifyRole(action string, role *Role, columns []string) (*Response, bool, error) {
+func (c *Client) modifyRole(action string, role *Role, columns []string) (*Response, bool, error) {
 	queryMap := map[string]string{
 		"id": fmt.Sprintf("%s/%s", role.Owner, role.Name),
 	}
@@ -274,13 +272,13 @@ func modifyRole(action string, role *Role, columns []string) (*Response, bool, e
 		queryMap["columns"] = strings.Join(columns, ",")
 	}
 
-	role.Owner = authConfig.OrganizationName
+	role.Owner = c.OrganizationName
 	postBytes, err := json.Marshal(role)
 	if err != nil {
 		return nil, false, err
 	}
 
-	resp, err := DoPost(action, queryMap, postBytes, false, false)
+	resp, err := c.DoPost(action, queryMap, postBytes, false, false)
 	if err != nil {
 		return nil, false, err
 	}
diff --git a/casdoorsdk/email.go b/casdoorsdk/email.go
index 0de58e7..0df5af3 100644
--- a/casdoorsdk/email.go
+++ b/casdoorsdk/email.go
@@ -26,7 +26,7 @@ type emailForm struct {
 	Receivers []string `json:"receivers"`
 }
 
-func SendEmail(title string, content string, sender string, receivers ...string) error {
+func (c *Client) SendEmail(title string, content string, sender string, receivers ...string) error {
 	form := emailForm{
 		Title:     title,
 		Content:   content,
@@ -38,7 +38,7 @@ func SendEmail(title string, content string, sender string, receivers ...string)
 		return err
 	}
 
-	resp, err := DoPost("send-email", nil, postBytes, false, false)
+	resp, err := c.DoPost("send-email", nil, postBytes, false, false)
 	if err != nil {
 		return err
 	}
@@ -49,3 +49,7 @@ func SendEmail(title string, content string, sender string, receivers ...string)
 
 	return nil
 }
+
+func SendEmail(title string, content string, sender string, receivers ...string) error {
+	return globalClient.SendEmail(title, content, sender, receivers...)
+}
diff --git a/casdoorsdk/enforce.go b/casdoorsdk/enforce.go
index 2cc80fa..0622eb5 100644
--- a/casdoorsdk/enforce.go
+++ b/casdoorsdk/enforce.go
@@ -32,13 +32,13 @@ type PermissionRule struct {
 
 type CasbinRequest = []interface{}
 
-func Enforce(permissionId, modelId, resourceId string, casbinRequest CasbinRequest) (bool, error) {
+func (c *Client) Enforce(permissionId, modelId, resourceId string, casbinRequest CasbinRequest) (bool, error) {
 	postBytes, err := json.Marshal(casbinRequest)
 	if err != nil {
 		return false, err
 	}
 
-	res, err := doEnforce("enforce", permissionId, modelId, resourceId, postBytes)
+	res, err := c.doEnforce("enforce", permissionId, modelId, resourceId, postBytes)
 	if err != nil {
 		return false, err
 	}
@@ -62,13 +62,17 @@ func Enforce(permissionId, modelId, resourceId string, casbinRequest CasbinReque
 	return false, nil
 }
 
-func BatchEnforce(permissionId, modelId, resourceId string, casbinRequests []CasbinRequest) ([][]bool, error) {
+func Enforce(permissionId, modelId, resourceId string, casbinRequest CasbinRequest) (bool, error) {
+	return globalClient.Enforce(permissionId, modelId, resourceId, casbinRequest)
+}
+
+func (c *Client) BatchEnforce(permissionId, modelId, resourceId string, casbinRequests []CasbinRequest) ([][]bool, error) {
 	postBytes, err := json.Marshal(casbinRequests)
 	if err != nil {
 		return nil, err
 	}
 
-	res, err := doEnforce("batch-enforce", permissionId, modelId, resourceId, postBytes)
+	res, err := c.doEnforce("batch-enforce", permissionId, modelId, resourceId, postBytes)
 	if err != nil {
 		return nil, err
 	}
@@ -98,15 +102,19 @@ func BatchEnforce(permissionId, modelId, resourceId string, casbinRequests []Cas
 	return allows, nil
 }
 
-func doEnforce(action string, permissionId, modelId, resourceId string, postBytes []byte) (*Response, error) {
+func BatchEnforce(permissionId, modelId, resourceId string, casbinRequests []CasbinRequest) ([][]bool, error) {
+	return globalClient.BatchEnforce(permissionId, modelId, resourceId, casbinRequests)
+}
+
+func (c *Client) doEnforce(action string, permissionId, modelId, resourceId string, postBytes []byte) (*Response, error) {
 	queryMap := map[string]string{
 		"permissionId": permissionId,
 		"modelId":      modelId,
 		"resourceId":   resourceId,
 	}
 
-	//bytes, err := DoPostBytesRaw(url, "", bytes.NewBuffer(postBytes))
-	resp, err := DoPost(action, queryMap, postBytes, false, false)
+	// bytes, err := DoPostBytesRaw(url, "", bytes.NewBuffer(postBytes))
+	resp, err := c.DoPost(action, queryMap, postBytes, false, false)
 	if err != nil {
 		return nil, err
 	}
diff --git a/casdoorsdk/jwt.go b/casdoorsdk/jwt.go
index 69d1a13..11496d7 100644
--- a/casdoorsdk/jwt.go
+++ b/casdoorsdk/jwt.go
@@ -26,13 +26,13 @@ type Claims struct {
 	jwt.RegisteredClaims
 }
 
-func ParseJwtToken(token string) (*Claims, error) {
+func (c *Client) ParseJwtToken(token string) (*Claims, error) {
 	t, err := jwt.ParseWithClaims(token, &Claims{}, func(token *jwt.Token) (interface{}, error) {
 		if _, ok := token.Method.(*jwt.SigningMethodRSA); !ok {
 			return nil, fmt.Errorf("unexpected signing method: %v", token.Header["alg"])
 		}
 
-		publicKey, err := jwt.ParseRSAPublicKeyFromPEM([]byte(authConfig.Certificate))
+		publicKey, err := jwt.ParseRSAPublicKeyFromPEM([]byte(c.Certificate))
 		if err != nil {
 			return nil, err
 		}
@@ -48,3 +48,7 @@ func ParseJwtToken(token string) (*Claims, error) {
 
 	return nil, err
 }
+
+func ParseJwtToken(token string) (*Claims, error) {
+	return globalClient.ParseJwtToken(token)
+}
diff --git a/casdoorsdk/organization.go b/casdoorsdk/organization.go
index 6c65dce..bbc5142 100644
--- a/casdoorsdk/organization.go
+++ b/casdoorsdk/organization.go
@@ -45,7 +45,7 @@ type Organization struct {
 	AccountItems []*AccountItem `xorm:"varchar(3000)" json:"accountItems"`
 }
 
-func AddOrganization(organization *Organization) (bool, error) {
+func (c *Client) AddOrganization(organization *Organization) (bool, error) {
 	if organization.Owner == "" {
 		organization.Owner = "admin"
 	}
@@ -54,7 +54,7 @@ func AddOrganization(organization *Organization) (bool, error) {
 		return false, err
 	}
 
-	resp, err := DoPost("add-organization", nil, postBytes, false, false)
+	resp, err := c.DoPost("add-organization", nil, postBytes, false, false)
 	if err != nil {
 		return false, err
 	}
@@ -62,7 +62,11 @@ func AddOrganization(organization *Organization) (bool, error) {
 	return resp.Data == "Affected", nil
 }
 
-func DeleteOrganization(name string) (bool, error) {
+func AddOrganization(organization *Organization) (bool, error) {
+	return globalClient.AddOrganization(organization)
+}
+
+func (c *Client) DeleteOrganization(name string) (bool, error) {
 	organization := Organization{
 		Owner: "admin",
 		Name:  name,
@@ -72,10 +76,14 @@ func DeleteOrganization(name string) (bool, error) {
 		return false, err
 	}
 
-	resp, err := DoPost("delete-organization", nil, postBytes, false, false)
+	resp, err := c.DoPost("delete-organization", nil, postBytes, false, false)
 	if err != nil {
 		return false, err
 	}
 
 	return resp.Data == "Affected", nil
 }
+
+func DeleteOrganization(name string) (bool, error) {
+	return globalClient.DeleteOrganization(name)
+}
diff --git a/casdoorsdk/permission.go b/casdoorsdk/permission.go
index 5b379f0..0d96d2c 100644
--- a/casdoorsdk/permission.go
+++ b/casdoorsdk/permission.go
@@ -44,14 +44,14 @@ type Permission struct {
 	State       string `xorm:"varchar(100)" json:"state"`
 }
 
-func GetPermissions() ([]*Permission, error) {
+func (c *Client) GetPermissions() ([]*Permission, error) {
 	queryMap := map[string]string{
-		"owner": authConfig.OrganizationName,
+		"owner": c.OrganizationName,
 	}
 
-	url := GetUrl("get-permissions", queryMap)
+	url := c.GetUrl("get-permissions", queryMap)
 
-	bytes, err := DoGetBytes(url)
+	bytes, err := c.DoGetBytes(url)
 	if err != nil {
 		return nil, err
 	}
@@ -64,14 +64,18 @@ func GetPermissions() ([]*Permission, error) {
 	return permissions, nil
 }
 
-func GetPermissionsByRole(name string) ([]*Permission, error) {
+func GetPermissions() ([]*Permission, error) {
+	return globalClient.GetPermissions()
+}
+
+func (c *Client) GetPermissionsByRole(name string) ([]*Permission, error) {
 	queryMap := map[string]string{
-		"id": fmt.Sprintf("%s/%s", authConfig.OrganizationName, name),
+		"id": fmt.Sprintf("%s/%s", c.OrganizationName, name),
 	}
 
-	url := GetUrl("get-permissions-by-role", queryMap)
+	url := c.GetUrl("get-permissions-by-role", queryMap)
 
-	bytes, err := DoGetBytes(url)
+	bytes, err := c.DoGetBytes(url)
 	if err != nil {
 		return nil, err
 	}
@@ -84,14 +88,18 @@ func GetPermissionsByRole(name string) ([]*Permission, error) {
 	return permissions, nil
 }
 
-func GetPaginationPermissions(p int, pageSize int, queryMap map[string]string) ([]*Permission, int, error) {
-	queryMap["owner"] = authConfig.OrganizationName
+func GetPermissionsByRole(name string) ([]*Permission, error) {
+	return globalClient.GetPermissionsByRole(name)
+}
+
+func (c *Client) GetPaginationPermissions(p int, pageSize int, queryMap map[string]string) ([]*Permission, int, error) {
+	queryMap["owner"] = c.OrganizationName
 	queryMap["p"] = strconv.Itoa(p)
 	queryMap["pageSize"] = strconv.Itoa(pageSize)
 
-	url := GetUrl("get-permissions", queryMap)
+	url := c.GetUrl("get-permissions", queryMap)
 
-	response, err := DoGetResponse(url)
+	response, err := c.DoGetResponse(url)
 	if err != nil {
 		return nil, 0, err
 	}
@@ -113,14 +121,18 @@ func GetPaginationPermissions(p int, pageSize int, queryMap map[string]string) (
 	return permissions, int(response.Data2.(float64)), nil
 }
 
-func GetPermission(name string) (*Permission, error) {
+func GetPaginationPermissions(p int, pageSize int, queryMap map[string]string) ([]*Permission, int, error) {
+	return globalClient.GetPaginationPermissions(p, pageSize, queryMap)
+}
+
+func (c *Client) GetPermission(name string) (*Permission, error) {
 	queryMap := map[string]string{
-		"id": fmt.Sprintf("%s/%s", authConfig.OrganizationName, name),
+		"id": fmt.Sprintf("%s/%s", c.OrganizationName, name),
 	}
 
-	url := GetUrl("get-permission", queryMap)
+	url := c.GetUrl("get-permission", queryMap)
 
-	bytes, err := DoGetBytes(url)
+	bytes, err := c.DoGetBytes(url)
 	if err != nil {
 		return nil, err
 	}
@@ -133,22 +145,42 @@ func GetPermission(name string) (*Permission, error) {
 	return permission, nil
 }
 
+func GetPermission(name string) (*Permission, error) {
+	return globalClient.GetPermission(name)
+}
+
+func (c *Client) UpdatePermission(permission *Permission) (bool, error) {
+	_, affected, err := c.modifyPermission("update-permission", permission, nil)
+	return affected, err
+}
+
 func UpdatePermission(permission *Permission) (bool, error) {
-	_, affected, err := modifyPermission("update-permission", permission, nil)
+	return globalClient.UpdatePermission(permission)
+}
+
+func (c *Client) UpdatePermissionForColumns(permission *Permission, columns []string) (bool, error) {
+	_, affected, err := c.modifyPermission("update-permission", permission, columns)
 	return affected, err
 }
 
 func UpdatePermissionForColumns(permission *Permission, columns []string) (bool, error) {
-	_, affected, err := modifyPermission("update-permission", permission, columns)
+	return globalClient.UpdatePermissionForColumns(permission, columns)
+}
+
+func (c *Client) AddPermission(permission *Permission) (bool, error) {
+	_, affected, err := c.modifyPermission("add-permission", permission, nil)
 	return affected, err
 }
 
 func AddPermission(permission *Permission) (bool, error) {
-	_, affected, err := modifyPermission("add-permission", permission, nil)
+	return globalClient.AddPermission(permission)
+}
+
+func (c *Client) DeletePermission(permission *Permission) (bool, error) {
+	_, affected, err := c.modifyPermission("delete-permission", permission, nil)
 	return affected, err
 }
 
 func DeletePermission(permission *Permission) (bool, error) {
-	_, affected, err := modifyPermission("delete-permission", permission, nil)
-	return affected, err
+	return globalClient.DeletePermission(permission)
 }
diff --git a/casdoorsdk/record.go b/casdoorsdk/record.go
index 685f446..f3c61ca 100644
--- a/casdoorsdk/record.go
+++ b/casdoorsdk/record.go
@@ -35,12 +35,12 @@ type Record struct {
 	IsTriggered bool `json:"isTriggered"`
 }
 
-func AddRecord(record *Record) (bool, error) {
+func (c *Client) AddRecord(record *Record) (bool, error) {
 	if record.Owner == "" {
-		record.Owner = authConfig.OrganizationName
+		record.Owner = c.OrganizationName
 	}
 	if record.Organization == "" {
-		record.Organization = authConfig.OrganizationName
+		record.Organization = c.OrganizationName
 	}
 
 	postBytes, err := json.Marshal(record)
@@ -48,10 +48,14 @@ func AddRecord(record *Record) (bool, error) {
 		return false, err
 	}
 
-	resp, err := DoPost("add-record", nil, postBytes, false, false)
+	resp, err := c.DoPost("add-record", nil, postBytes, false, false)
 	if err != nil {
 		return false, err
 	}
 
 	return resp.Data == "Affected", nil
 }
+
+func AddRecord(record *Record) (bool, error) {
+	return globalClient.AddRecord(record)
+}
diff --git a/casdoorsdk/resource.go b/casdoorsdk/resource.go
index dc260ba..2890a61 100644
--- a/casdoorsdk/resource.go
+++ b/casdoorsdk/resource.go
@@ -39,15 +39,15 @@ type Resource struct {
 	Description string `xorm:"varchar(1000)" json:"description"`
 }
 
-func GetResource(id string) (*Resource, error) {
+func (c *Client) GetResource(id string) (*Resource, error) {
 	queryMap := map[string]string{
-		"owner": authConfig.OrganizationName,
+		"owner": c.OrganizationName,
 		"id":    id,
 	}
 
-	url := GetUrl("get-resource", queryMap)
+	url := c.GetUrl("get-resource", queryMap)
 
-	bytes, err := DoGetBytes(url)
+	bytes, err := c.DoGetBytes(url)
 	if err != nil {
 		return nil, err
 	}
@@ -61,11 +61,19 @@ func GetResource(id string) (*Resource, error) {
 	return resource, nil
 }
 
+func GetResource(id string) (*Resource, error) {
+	return globalClient.GetResource(id)
+}
+
+func (c *Client) GetResourceEx(owner, name string) (*Resource, error) {
+	return c.GetResource(fmt.Sprintf("%s/%s", owner, name))
+}
+
 func GetResourceEx(owner, name string) (*Resource, error) {
-	return GetResource(fmt.Sprintf("%s/%s", owner, name))
+	return globalClient.GetResourceEx(owner, name)
 }
 
-func GetResources(owner, user, field, value, sortField, sortOrder string) ([]*Resource, error) {
+func (c *Client) GetResources(owner, user, field, value, sortField, sortOrder string) ([]*Resource, error) {
 	queryMap := map[string]string{
 		"owner":     owner,
 		"user":      user,
@@ -75,9 +83,9 @@ func GetResources(owner, user, field, value, sortField, sortOrder string) ([]*Re
 		"sortOrder": sortOrder,
 	}
 
-	url := GetUrl("get-resources", queryMap)
+	url := c.GetUrl("get-resources", queryMap)
 
-	bytes, err := DoGetBytes(url)
+	bytes, err := c.DoGetBytes(url)
 	if err != nil {
 		return nil, err
 	}
@@ -90,7 +98,11 @@ func GetResources(owner, user, field, value, sortField, sortOrder string) ([]*Re
 	return resources, nil
 }
 
-func GetPaginationResources(owner, user, field, value string, pageSize, page int, sortField, sortOrder string) ([]*Resource, error) {
+func GetResources(owner, user, field, value, sortField, sortOrder string) ([]*Resource, error) {
+	return globalClient.GetResources(owner, user, field, value, sortField, sortOrder)
+}
+
+func (c *Client) GetPaginationResources(owner, user, field, value string, pageSize, page int, sortField, sortOrder string) ([]*Resource, error) {
 	queryMap := map[string]string{
 		"owner":     owner,
 		"user":      user,
@@ -102,9 +114,9 @@ func GetPaginationResources(owner, user, field, value string, pageSize, page int
 		"sortOrder": sortOrder,
 	}
 
-	url := GetUrl("get-resources", queryMap)
+	url := c.GetUrl("get-resources", queryMap)
 
-	bytes, err := DoGetBytes(url)
+	bytes, err := c.DoGetBytes(url)
 	if err != nil {
 		return nil, err
 	}
@@ -117,17 +129,21 @@ func GetPaginationResources(owner, user, field, value string, pageSize, page int
 	return resources, nil
 }
 
-func UploadResource(user string, tag string, parent string, fullFilePath string, fileBytes []byte) (string, string, error) {
+func GetPaginationResources(owner, user, field, value string, pageSize, page int, sortField, sortOrder string) ([]*Resource, error) {
+	return globalClient.GetPaginationResources(owner, user, field, value, pageSize, page, sortField, sortOrder)
+}
+
+func (c *Client) UploadResource(user string, tag string, parent string, fullFilePath string, fileBytes []byte) (string, string, error) {
 	queryMap := map[string]string{
-		"owner":        authConfig.OrganizationName,
+		"owner":        c.OrganizationName,
 		"user":         user,
-		"application":  authConfig.ApplicationName,
+		"application":  c.ApplicationName,
 		"tag":          tag,
 		"parent":       parent,
 		"fullFilePath": fullFilePath,
 	}
 
-	resp, err := DoPost("upload-resource", queryMap, fileBytes, true, true)
+	resp, err := c.DoPost("upload-resource", queryMap, fileBytes, true, true)
 	if err != nil {
 		return "", "", err
 	}
@@ -141,11 +157,15 @@ func UploadResource(user string, tag string, parent string, fullFilePath string,
 	return fileUrl, name, nil
 }
 
-func UploadResourceEx(user string, tag string, parent string, fullFilePath string, fileBytes []byte, createdTime string, description string) (string, string, error) {
+func UploadResource(user string, tag string, parent string, fullFilePath string, fileBytes []byte) (string, string, error) {
+	return globalClient.UploadResource(user, tag, parent, fullFilePath, fileBytes)
+}
+
+func (c *Client) UploadResourceEx(user string, tag string, parent string, fullFilePath string, fileBytes []byte, createdTime string, description string) (string, string, error) {
 	queryMap := map[string]string{
-		"owner":        authConfig.OrganizationName,
+		"owner":        c.OrganizationName,
 		"user":         user,
-		"application":  authConfig.ApplicationName,
+		"application":  c.ApplicationName,
 		"tag":          tag,
 		"parent":       parent,
 		"fullFilePath": fullFilePath,
@@ -153,7 +173,7 @@ func UploadResourceEx(user string, tag string, parent string, fullFilePath strin
 		"description":  description,
 	}
 
-	resp, err := DoPost("upload-resource", queryMap, fileBytes, true, true)
+	resp, err := c.DoPost("upload-resource", queryMap, fileBytes, true, true)
 	if err != nil {
 		return "", "", err
 	}
@@ -167,9 +187,13 @@ func UploadResourceEx(user string, tag string, parent string, fullFilePath strin
 	return fileUrl, name, nil
 }
 
-func DeleteResource(name string) (bool, error) {
+func UploadResourceEx(user string, tag string, parent string, fullFilePath string, fileBytes []byte, createdTime string, description string) (string, string, error) {
+	return globalClient.UploadResourceEx(user, tag, parent, fullFilePath, fileBytes, createdTime, description)
+}
+
+func (c *Client) DeleteResource(name string) (bool, error) {
 	resource := Resource{
-		Owner: authConfig.OrganizationName,
+		Owner: c.OrganizationName,
 		Name:  name,
 	}
 	postBytes, err := json.Marshal(resource)
@@ -177,10 +201,14 @@ func DeleteResource(name string) (bool, error) {
 		return false, err
 	}
 
-	resp, err := DoPost("delete-resource", nil, postBytes, false, false)
+	resp, err := c.DoPost("delete-resource", nil, postBytes, false, false)
 	if err != nil {
 		return false, err
 	}
 
 	return resp.Data == "Affected", nil
 }
+
+func DeleteResource(name string) (bool, error) {
+	return globalClient.DeleteResource(name)
+}
diff --git a/casdoorsdk/role.go b/casdoorsdk/role.go
index 3ee8217..4748948 100644
--- a/casdoorsdk/role.go
+++ b/casdoorsdk/role.go
@@ -33,14 +33,14 @@ type Role struct {
 	IsEnabled bool     `json:"isEnabled"`
 }
 
-func GetRoles() ([]*Role, error) {
+func (c *Client) GetRoles() ([]*Role, error) {
 	queryMap := map[string]string{
-		"owner": authConfig.OrganizationName,
+		"owner": c.OrganizationName,
 	}
 
-	url := GetUrl("get-roles", queryMap)
+	url := c.GetUrl("get-roles", queryMap)
 
-	bytes, err := DoGetBytes(url)
+	bytes, err := c.DoGetBytes(url)
 	if err != nil {
 		return nil, err
 	}
@@ -53,14 +53,18 @@ func GetRoles() ([]*Role, error) {
 	return roles, nil
 }
 
-func GetPaginationRoles(p int, pageSize int, queryMap map[string]string) ([]*Role, int, error) {
-	queryMap["owner"] = authConfig.OrganizationName
+func GetRoles() ([]*Role, error) {
+	return globalClient.GetRoles()
+}
+
+func (c *Client) GetPaginationRoles(p int, pageSize int, queryMap map[string]string) ([]*Role, int, error) {
+	queryMap["owner"] = c.OrganizationName
 	queryMap["p"] = strconv.Itoa(p)
 	queryMap["pageSize"] = strconv.Itoa(pageSize)
 
-	url := GetUrl("get-roles", queryMap)
+	url := c.GetUrl("get-roles", queryMap)
 
-	response, err := DoGetResponse(url)
+	response, err := c.DoGetResponse(url)
 	if err != nil {
 		return nil, 0, err
 	}
@@ -78,14 +82,18 @@ func GetPaginationRoles(p int, pageSize int, queryMap map[string]string) ([]*Rol
 	return roles, int(response.Data2.(float64)), nil
 }
 
-func GetRole(name string) (*Role, error) {
+func GetPaginationRoles(p int, pageSize int, queryMap map[string]string) ([]*Role, int, error) {
+	return globalClient.GetPaginationRoles(p, pageSize, queryMap)
+}
+
+func (c *Client) GetRole(name string) (*Role, error) {
 	queryMap := map[string]string{
-		"id": fmt.Sprintf("%s/%s", authConfig.OrganizationName, name),
+		"id": fmt.Sprintf("%s/%s", c.OrganizationName, name),
 	}
 
-	url := GetUrl("get-role", queryMap)
+	url := c.GetUrl("get-role", queryMap)
 
-	bytes, err := DoGetBytes(url)
+	bytes, err := c.DoGetBytes(url)
 	if err != nil {
 		return nil, err
 	}
@@ -98,22 +106,42 @@ func GetRole(name string) (*Role, error) {
 	return role, nil
 }
 
+func GetRole(name string) (*Role, error) {
+	return globalClient.GetRole(name)
+}
+
+func (c *Client) UpdateRole(role *Role) (bool, error) {
+	_, affected, err := c.modifyRole("update-role", role, nil)
+	return affected, err
+}
+
 func UpdateRole(role *Role) (bool, error) {
-	_, affected, err := modifyRole("update-role", role, nil)
+	return globalClient.UpdateRole(role)
+}
+
+func (c *Client) UpdateRoleForColumns(role *Role, columns []string) (bool, error) {
+	_, affected, err := c.modifyRole("update-role", role, columns)
 	return affected, err
 }
 
 func UpdateRoleForColumns(role *Role, columns []string) (bool, error) {
-	_, affected, err := modifyRole("update-role", role, columns)
+	return globalClient.UpdateRoleForColumns(role, columns)
+}
+
+func (c *Client) AddRole(role *Role) (bool, error) {
+	_, affected, err := c.modifyRole("add-role", role, nil)
 	return affected, err
 }
 
 func AddRole(role *Role) (bool, error) {
-	_, affected, err := modifyRole("add-role", role, nil)
+	return globalClient.AddRole(role)
+}
+
+func (c *Client) DeleteRole(role *Role) (bool, error) {
+	_, affected, err := c.modifyRole("delete-role", role, nil)
 	return affected, err
 }
 
 func DeleteRole(role *Role) (bool, error) {
-	_, affected, err := modifyRole("delete-role", role, nil)
-	return affected, err
+	return globalClient.DeleteRole(role)
 }
diff --git a/casdoorsdk/sms.go b/casdoorsdk/sms.go
index 61839ba..9293260 100644
--- a/casdoorsdk/sms.go
+++ b/casdoorsdk/sms.go
@@ -24,7 +24,7 @@ type smsForm struct {
 	Receivers []string `json:"receivers"`
 }
 
-func SendSms(content string, receivers ...string) error {
+func (c *Client) SendSms(content string, receivers ...string) error {
 	form := smsForm{
 		Content:   content,
 		Receivers: receivers,
@@ -34,7 +34,7 @@ func SendSms(content string, receivers ...string) error {
 		return err
 	}
 
-	resp, err := DoPost("send-sms", nil, postBytes, false, false)
+	resp, err := c.DoPost("send-sms", nil, postBytes, false, false)
 	if err != nil {
 		return err
 	}
@@ -45,3 +45,7 @@ func SendSms(content string, receivers ...string) error {
 
 	return nil
 }
+
+func SendSms(content string, receivers ...string) error {
+	return globalClient.SendSms(content, receivers...)
+}
diff --git a/casdoorsdk/token.go b/casdoorsdk/token.go
index 5cd58b6..a80824c 100644
--- a/casdoorsdk/token.go
+++ b/casdoorsdk/token.go
@@ -47,13 +47,13 @@ type Token struct {
 }
 
 // GetOAuthToken gets the pivotal and necessary secret to interact with the Casdoor server
-func GetOAuthToken(code string, state string) (*oauth2.Token, error) {
+func (c *Client) GetOAuthToken(code string, state string) (*oauth2.Token, error) {
 	config := oauth2.Config{
-		ClientID:     authConfig.ClientId,
-		ClientSecret: authConfig.ClientSecret,
+		ClientID:     c.ClientId,
+		ClientSecret: c.ClientSecret,
 		Endpoint: oauth2.Endpoint{
-			AuthURL:   fmt.Sprintf("%s/api/login/oauth/authorize", authConfig.Endpoint),
-			TokenURL:  fmt.Sprintf("%s/api/login/oauth/access_token", authConfig.Endpoint),
+			AuthURL:   fmt.Sprintf("%s/api/login/oauth/authorize", c.Endpoint),
+			TokenURL:  fmt.Sprintf("%s/api/login/oauth/access_token", c.Endpoint),
 			AuthStyle: oauth2.AuthStyleInParams,
 		},
 		// RedirectURL: redirectUri,
@@ -72,14 +72,18 @@ func GetOAuthToken(code string, state string) (*oauth2.Token, error) {
 	return token, err
 }
 
+func GetOAuthToken(code string, state string) (*oauth2.Token, error) {
+	return globalClient.GetOAuthToken(code, state)
+}
+
 // RefreshOAuthToken refreshes the OAuth token
-func RefreshOAuthToken(refreshToken string) (*oauth2.Token, error) {
+func (c *Client) RefreshOAuthToken(refreshToken string) (*oauth2.Token, error) {
 	config := oauth2.Config{
-		ClientID:     authConfig.ClientId,
-		ClientSecret: authConfig.ClientSecret,
+		ClientID:     c.ClientId,
+		ClientSecret: c.ClientSecret,
 		Endpoint: oauth2.Endpoint{
-			AuthURL:   fmt.Sprintf("%s/api/login/oauth/authorize", authConfig.Endpoint),
-			TokenURL:  fmt.Sprintf("%s/api/login/oauth/refresh_token", authConfig.Endpoint),
+			AuthURL:   fmt.Sprintf("%s/api/login/oauth/authorize", c.Endpoint),
+			TokenURL:  fmt.Sprintf("%s/api/login/oauth/refresh_token", c.Endpoint),
 			AuthStyle: oauth2.AuthStyleInParams,
 		},
 		// RedirectURL: redirectUri,
@@ -98,16 +102,20 @@ func RefreshOAuthToken(refreshToken string) (*oauth2.Token, error) {
 	return token, err
 }
 
-func GetTokens(p int, pageSize int) ([]*Token, int, error) {
+func RefreshOAuthToken(refreshToken string) (*oauth2.Token, error) {
+	return globalClient.RefreshOAuthToken(refreshToken)
+}
+
+func (c *Client) GetTokens(p int, pageSize int) ([]*Token, int, error) {
 	queryMap := map[string]string{
-		"owner":    authConfig.OrganizationName,
+		"owner":    c.OrganizationName,
 		"p":        strconv.Itoa(p),
 		"pageSize": strconv.Itoa(pageSize),
 	}
 
-	url := GetUrl("get-tokens", queryMap)
+	url := c.GetUrl("get-tokens", queryMap)
 
-	response, err := DoGetResponse(url)
+	response, err := c.DoGetResponse(url)
 	if err != nil {
 		return nil, 0, err
 	}
@@ -125,7 +133,11 @@ func GetTokens(p int, pageSize int) ([]*Token, int, error) {
 	return tokens, int(response.Data2.(float64)), nil
 }
 
-func DeleteToken(name string) (bool, error) {
+func GetTokens(p int, pageSize int) ([]*Token, int, error) {
+	return globalClient.GetTokens(p, pageSize)
+}
+
+func (c *Client) DeleteToken(name string) (bool, error) {
 	organization := Organization{
 		Owner: "admin",
 		Name:  name,
@@ -135,10 +147,14 @@ func DeleteToken(name string) (bool, error) {
 		return false, err
 	}
 
-	resp, err := DoPost("delete-token", nil, postBytes, false, false)
+	resp, err := c.DoPost("delete-token", nil, postBytes, false, false)
 	if err != nil {
 		return false, err
 	}
 
 	return resp.Data == "Affected", nil
 }
+
+func DeleteToken(name string) (bool, error) {
+	return globalClient.DeleteToken(name)
+}
diff --git a/casdoorsdk/url.go b/casdoorsdk/url.go
index ca441f9..0969379 100644
--- a/casdoorsdk/url.go
+++ b/casdoorsdk/url.go
@@ -20,36 +20,52 @@ import (
 	"strings"
 )
 
-func GetSignupUrl(enablePassword bool, redirectUri string) string {
+func (c *Client) GetSignupUrl(enablePassword bool, redirectUri string) string {
 	// redirectUri can be empty string if enablePassword == true (only password enabled signup page is required)
 	if enablePassword {
-		return fmt.Sprintf("%s/signup/%s", authConfig.Endpoint, authConfig.ApplicationName)
+		return fmt.Sprintf("%s/signup/%s", c.Endpoint, c.ApplicationName)
 	} else {
-		return strings.ReplaceAll(GetSigninUrl(redirectUri), "/login/oauth/authorize", "/signup/oauth/authorize")
+		return strings.ReplaceAll(c.GetSigninUrl(redirectUri), "/login/oauth/authorize", "/signup/oauth/authorize")
 	}
 }
 
-func GetSigninUrl(redirectUri string) string {
+func GetSignupUrl(enablePassword bool, redirectUri string) string {
+	return globalClient.GetSignupUrl(enablePassword, redirectUri)
+}
+
+func (c *Client) GetSigninUrl(redirectUri string) string {
 	// origin := "https://door.casbin.com"
 	// redirectUri := fmt.Sprintf("%s/callback", origin)
 	scope := "read"
-	state := authConfig.ApplicationName
+	state := c.ApplicationName
 	return fmt.Sprintf("%s/login/oauth/authorize?client_id=%s&response_type=code&redirect_uri=%s&scope=%s&state=%s",
-		authConfig.Endpoint, authConfig.ClientId, url.QueryEscape(redirectUri), scope, state)
+		c.Endpoint, c.ClientId, url.QueryEscape(redirectUri), scope, state)
 }
 
-func GetUserProfileUrl(userName string, accessToken string) string {
+func GetSigninUrl(redirectUri string) string {
+	return globalClient.GetSigninUrl(redirectUri)
+}
+
+func (c *Client) GetUserProfileUrl(userName string, accessToken string) string {
 	param := ""
 	if accessToken != "" {
 		param = fmt.Sprintf("?access_token=%s", accessToken)
 	}
-	return fmt.Sprintf("%s/users/%s/%s%s", authConfig.Endpoint, authConfig.OrganizationName, userName, param)
+	return fmt.Sprintf("%s/users/%s/%s%s", c.Endpoint, c.OrganizationName, userName, param)
 }
 
-func GetMyProfileUrl(accessToken string) string {
+func GetUserProfileUrl(userName string, accessToken string) string {
+	return globalClient.GetUserProfileUrl(userName, accessToken)
+}
+
+func (c *Client) GetMyProfileUrl(accessToken string) string {
 	param := ""
 	if accessToken != "" {
 		param = fmt.Sprintf("?access_token=%s", accessToken)
 	}
-	return fmt.Sprintf("%s/account%s", authConfig.Endpoint, param)
+	return fmt.Sprintf("%s/account%s", c.Endpoint, param)
+}
+
+func GetMyProfileUrl(accessToken string) string {
+	return globalClient.GetMyProfileUrl(accessToken)
 }
diff --git a/casdoorsdk/user.go b/casdoorsdk/user.go
index 99d3526..1d01c56 100644
--- a/casdoorsdk/user.go
+++ b/casdoorsdk/user.go
@@ -173,14 +173,14 @@ type User struct {
 	ManagedAccounts []ManagedAccount `xorm:"managedAccounts blob" json:"managedAccounts"`
 }
 
-func GetUsers() ([]*User, error) {
+func (c *Client) GetUsers() ([]*User, error) {
 	queryMap := map[string]string{
-		"owner": authConfig.OrganizationName,
+		"owner": c.OrganizationName,
 	}
 
-	url := GetUrl("get-users", queryMap)
+	url := c.GetUrl("get-users", queryMap)
 
-	bytes, err := DoGetBytes(url)
+	bytes, err := c.DoGetBytes(url)
 	if err != nil {
 		return nil, err
 	}
@@ -193,16 +193,20 @@ func GetUsers() ([]*User, error) {
 	return users, nil
 }
 
-func GetSortedUsers(sorter string, limit int) ([]*User, error) {
+func GetUsers() ([]*User, error) {
+	return globalClient.GetUsers()
+}
+
+func (c *Client) GetSortedUsers(sorter string, limit int) ([]*User, error) {
 	queryMap := map[string]string{
-		"owner":  authConfig.OrganizationName,
+		"owner":  c.OrganizationName,
 		"sorter": sorter,
 		"limit":  strconv.Itoa(limit),
 	}
 
-	url := GetUrl("get-sorted-users", queryMap)
+	url := c.GetUrl("get-sorted-users", queryMap)
 
-	bytes, err := DoGetBytes(url)
+	bytes, err := c.DoGetBytes(url)
 	if err != nil {
 		return nil, err
 	}
@@ -215,14 +219,18 @@ func GetSortedUsers(sorter string, limit int) ([]*User, error) {
 	return users, nil
 }
 
-func GetPaginationUsers(p int, pageSize int, queryMap map[string]string) ([]*User, int, error) {
-	queryMap["owner"] = authConfig.OrganizationName
+func GetSortedUsers(sorter string, limit int) ([]*User, error) {
+	return globalClient.GetSortedUsers(sorter, limit)
+}
+
+func (c *Client) GetPaginationUsers(p int, pageSize int, queryMap map[string]string) ([]*User, int, error) {
+	queryMap["owner"] = c.OrganizationName
 	queryMap["p"] = strconv.Itoa(p)
 	queryMap["pageSize"] = strconv.Itoa(pageSize)
 
-	url := GetUrl("get-users", queryMap)
+	url := c.GetUrl("get-users", queryMap)
 
-	response, err := DoGetResponse(url)
+	response, err := c.DoGetResponse(url)
 	if err != nil {
 		return nil, 0, err
 	}
@@ -244,15 +252,19 @@ func GetPaginationUsers(p int, pageSize int, queryMap map[string]string) ([]*Use
 	return users, int(response.Data2.(float64)), nil
 }
 
-func GetUserCount(isOnline string) (int, error) {
+func GetPaginationUsers(p int, pageSize int, queryMap map[string]string) ([]*User, int, error) {
+	return globalClient.GetPaginationUsers(p, pageSize, queryMap)
+}
+
+func (c *Client) GetUserCount(isOnline string) (int, error) {
 	queryMap := map[string]string{
-		"owner":    authConfig.OrganizationName,
+		"owner":    c.OrganizationName,
 		"isOnline": isOnline,
 	}
 
-	url := GetUrl("get-user-count", queryMap)
+	url := c.GetUrl("get-user-count", queryMap)
 
-	bytes, err := DoGetBytes(url)
+	bytes, err := c.DoGetBytes(url)
 	if err != nil {
 		return -1, err
 	}
@@ -265,14 +277,18 @@ func GetUserCount(isOnline string) (int, error) {
 	return count, nil
 }
 
-func GetUser(name string) (*User, error) {
+func GetUserCount(isOnline string) (int, error) {
+	return globalClient.GetUserCount(isOnline)
+}
+
+func (c *Client) GetUser(name string) (*User, error) {
 	queryMap := map[string]string{
-		"id": fmt.Sprintf("%s/%s", authConfig.OrganizationName, name),
+		"id": fmt.Sprintf("%s/%s", c.OrganizationName, name),
 	}
 
-	url := GetUrl("get-user", queryMap)
+	url := c.GetUrl("get-user", queryMap)
 
-	bytes, err := DoGetBytes(url)
+	bytes, err := c.DoGetBytes(url)
 	if err != nil {
 		return nil, err
 	}
@@ -285,15 +301,19 @@ func GetUser(name string) (*User, error) {
 	return user, nil
 }
 
-func GetUserByEmail(email string) (*User, error) {
+func GetUser(name string) (*User, error) {
+	return globalClient.GetUser(name)
+}
+
+func (c *Client) GetUserByEmail(email string) (*User, error) {
 	queryMap := map[string]string{
-		"owner": authConfig.OrganizationName,
+		"owner": c.OrganizationName,
 		"email": email,
 	}
 
-	url := GetUrl("get-user", queryMap)
+	url := c.GetUrl("get-user", queryMap)
 
-	bytes, err := DoGetBytes(url)
+	bytes, err := c.DoGetBytes(url)
 	if err != nil {
 		return nil, err
 	}
@@ -306,15 +326,19 @@ func GetUserByEmail(email string) (*User, error) {
 	return user, nil
 }
 
-func GetUserByPhone(phone string) (*User, error) {
+func GetUserByEmail(email string) (*User, error) {
+	return globalClient.GetUserByEmail(email)
+}
+
+func (c *Client) GetUserByPhone(phone string) (*User, error) {
 	queryMap := map[string]string{
-		"owner": authConfig.OrganizationName,
+		"owner": c.OrganizationName,
 		"phone": phone,
 	}
 
-	url := GetUrl("get-user", queryMap)
+	url := c.GetUrl("get-user", queryMap)
 
-	bytes, err := DoGetBytes(url)
+	bytes, err := c.DoGetBytes(url)
 	if err != nil {
 		return nil, err
 	}
@@ -327,15 +351,19 @@ func GetUserByPhone(phone string) (*User, error) {
 	return user, nil
 }
 
-func GetUserByUserId(userId string) (*User, error) {
+func GetUserByPhone(phone string) (*User, error) {
+	return globalClient.GetUserByPhone(phone)
+}
+
+func (c *Client) GetUserByUserId(userId string) (*User, error) {
 	queryMap := map[string]string{
-		"owner":  authConfig.OrganizationName,
+		"owner":  c.OrganizationName,
 		"userId": userId,
 	}
 
-	url := GetUrl("get-user", queryMap)
+	url := c.GetUrl("get-user", queryMap)
 
-	bytes, err := DoGetBytes(url)
+	bytes, err := c.DoGetBytes(url)
 	if err != nil {
 		return nil, err
 	}
@@ -348,8 +376,12 @@ func GetUserByUserId(userId string) (*User, error) {
 	return user, nil
 }
 
+func GetUserByUserId(userId string) (*User, error) {
+	return globalClient.GetUserByUserId(userId)
+}
+
 // note: oldPassword is not required, if you don't need, just pass a empty string
-func SetPassword(owner, name, oldPassword, newPassword string) (bool, error) {
+func (c *Client) SetPassword(owner, name, oldPassword, newPassword string) (bool, error) {
 	param := map[string]string{
 		"userOwner":   owner,
 		"userName":    name,
@@ -362,7 +394,7 @@ func SetPassword(owner, name, oldPassword, newPassword string) (bool, error) {
 		return false, err
 	}
 
-	resp, err := DoPost("set-password", nil, bytes, true, false)
+	resp, err := c.DoPost("set-password", nil, bytes, true, false)
 	if err != nil {
 		return false, err
 	}
@@ -370,36 +402,65 @@ func SetPassword(owner, name, oldPassword, newPassword string) (bool, error) {
 	return resp.Status == "ok", nil
 }
 
+// note: oldPassword is not required, if you don't need, just pass a empty string
+func SetPassword(owner, name, oldPassword, newPassword string) (bool, error) {
+	return globalClient.SetPassword(owner, name, oldPassword, newPassword)
+}
+
+func (c *Client) UpdateUserById(id string, user *User) (bool, error) {
+	_, affected, err := c.modifyUserById("update-user", id, user, nil)
+	return affected, err
+}
+
 func UpdateUserById(id string, user *User) (bool, error) {
-	_, affected, err := modifyUserById("update-user", id, user, nil)
+	return globalClient.UpdateUserById(id, user)
+}
+
+func (c *Client) UpdateUser(user *User) (bool, error) {
+	_, affected, err := c.modifyUser("update-user", user, nil)
 	return affected, err
 }
 
 func UpdateUser(user *User) (bool, error) {
-	_, affected, err := modifyUser("update-user", user, nil)
+	return globalClient.UpdateUser(user)
+}
+
+func (c *Client) UpdateUserForColumns(user *User, columns []string) (bool, error) {
+	_, affected, err := c.modifyUser("update-user", user, columns)
 	return affected, err
 }
 
 func UpdateUserForColumns(user *User, columns []string) (bool, error) {
-	_, affected, err := modifyUser("update-user", user, columns)
+	return globalClient.UpdateUserForColumns(user, columns)
+}
+
+func (c *Client) AddUser(user *User) (bool, error) {
+	_, affected, err := c.modifyUser("add-user", user, nil)
 	return affected, err
 }
 
 func AddUser(user *User) (bool, error) {
-	_, affected, err := modifyUser("add-user", user, nil)
+	return globalClient.AddUser(user)
+}
+
+func (c *Client) DeleteUser(user *User) (bool, error) {
+	_, affected, err := c.modifyUser("delete-user", user, nil)
 	return affected, err
 }
 
 func DeleteUser(user *User) (bool, error) {
-	_, affected, err := modifyUser("delete-user", user, nil)
-	return affected, err
+	return globalClient.DeleteUser(user)
 }
 
-func CheckUserPassword(user *User) (bool, error) {
-	response, _, err := modifyUser("check-user-password", user, nil)
+func (c *Client) CheckUserPassword(user *User) (bool, error) {
+	response, _, err := c.modifyUser("check-user-password", user, nil)
 	return response.Status == "ok", err
 }
 
+func CheckUserPassword(user *User) (bool, error) {
+	return globalClient.CheckUserPassword(user)
+}
+
 func (u User) GetId() string {
 	return fmt.Sprintf("%s/%s", u.Owner, u.Name)
 }
diff --git a/casdoorsdk/util.go b/casdoorsdk/util.go
index f981c70..8243b79 100644
--- a/casdoorsdk/util.go
+++ b/casdoorsdk/util.go
@@ -22,19 +22,19 @@ import (
 	"strings"
 )
 
-func GetUrl(action string, queryMap map[string]string) string {
+func (c *Client) GetUrl(action string, queryMap map[string]string) string {
 	query := ""
 	for k, v := range queryMap {
 		query += fmt.Sprintf("%s=%s&", k, v)
 	}
 	query = strings.TrimRight(query, "&")
 
-	url := fmt.Sprintf("%s/api/%s?%s", authConfig.Endpoint, action, query)
+	url := fmt.Sprintf("%s/api/%s?%s", c.Endpoint, action, query)
 	return url
 }
 
-func GetId(name string) string {
-	return authConfig.OrganizationName + "/" + name
+func (c *Client) GetId(name string) string {
+	return c.OrganizationName + "/" + name
 }
 
 func createFormFile(formData map[string][]byte) (string, io.Reader, error) {