refactor(service): Separate out login into LoginWithQRCode and LoginWithSessionCredentials

service/whatsapp/README.md

@@ -8,7 +8,17 @@ You will need a registered WhatsApp phone number to be used as source for sendin
 
 ## Usage
 
-In the current implementation, authentication requires scanning QR code from terminal using a registered WhatsApp device. Please refer [Login (go-whatsapp)](https://github.com/Rhymen/go-whatsapp#login) and [sigalor/whatsapp-web-reveng](https://github.com/sigalor/whatsapp-web-reveng) for more details.
+In the current implementation, authentication is implemented using 2 ways:
+
+1. Scanning QR code from terminal using a registered WhatsApp device.
+
+    - Go to WhatsApp on your device.
+    - Click on the ellipsis icon (3 vertical dots) on top right, then click on "WhatsApp Web".
+    - Click on the "+" icon and scan the QR code from terminal.
+
+> Refer: [Login (go-whatsapp)](https://github.com/Rhymen/go-whatsapp#login) and [sigalor/whatsapp-web-reveng](https://github.com/sigalor/whatsapp-web-reveng) for more details.
+
+2. Providing the Session credentials explicitly.
 
 ```go
 package main
@@ -26,6 +36,11 @@ func main() {
                 log.Fatalf("whatsapp.New() failed: %s", err.Error())
         }
 
+        err = whatsappSvc.LoginWithQRCode()
+        if err != nil {
+                log.Fatalf("whatsappSvc.LoginWithQRCode() failed: %s", err.Error())
+        }
+
         whatsappSvc.AddReceivers("Contact1")
 
         notifier := notify.New()

service/whatsapp/doc.go

@@ -18,6 +18,11 @@ Usage:
 			log.Fatalf("whatsapp.New() failed: %s", err.Error())
 		}
 
+		err = whatsappSvc.LoginWithQRCode()
+		if err != nil {
+			log.Fatalf("whatsappSvc.LoginWithQRCode() failed: %s", err.Error())
+		}
+
 		whatsappSvc.AddReceivers("Contact1")
 
 		notifier := notify.New()

service/whatsapp/mock_whatsappClient.go

@@ -2,13 +2,58 @@
 
 package whatsapp
 
-import mock "github.com/stretchr/testify/mock"
+import (
+	"github.com/Rhymen/go-whatsapp"
+	"github.com/stretchr/testify/mock"
+)
 
 // mockWhatsappClient is an autogenerated mock type for the whatsappClient type
 type mockWhatsappClient struct {
 	mock.Mock
 }
 
+// Login provides a mock function with given fields: qrChan
+func (_m *mockWhatsappClient) Login(qrChan chan<- string) (whatsapp.Session, error) {
+	ret := _m.Called(qrChan)
+
+	var r0 whatsapp.Session
+	if rf, ok := ret.Get(0).(func(chan<- string) whatsapp.Session); ok {
+		r0 = rf(qrChan)
+	} else {
+		r0 = ret.Get(0).(whatsapp.Session)
+	}
+
+	var r1 error
+	if rf, ok := ret.Get(1).(func(chan<- string) error); ok {
+		r1 = rf(qrChan)
+	} else {
+		r1 = ret.Error(1)
+	}
+
+	return r0, r1
+}
+
+// RestoreWithSession provides a mock function with given fields: session
+func (_m *mockWhatsappClient) RestoreWithSession(session whatsapp.Session) (whatsapp.Session, error) {
+	ret := _m.Called(session)
+
+	var r0 whatsapp.Session
+	if rf, ok := ret.Get(0).(func(whatsapp.Session) whatsapp.Session); ok {
+		r0 = rf(session)
+	} else {
+		r0 = ret.Get(0).(whatsapp.Session)
+	}
+
+	var r1 error
+	if rf, ok := ret.Get(1).(func(whatsapp.Session) error); ok {
+		r1 = rf(session)
+	} else {
+		r1 = ret.Error(1)
+	}
+
+	return r0, r1
+}
+
 // Send provides a mock function with given fields: msg
 func (_m *mockWhatsappClient) Send(msg interface{}) (string, error) {
 	ret := _m.Called(msg)

service/whatsapp/whatsapp.go

@@ -7,17 +7,19 @@ import (
 	"time"
 
 	qrcodeTerminal "github.com/Baozisoftware/qrcode-terminal-go"
-	whatsapp "github.com/Rhymen/go-whatsapp"
+	"github.com/Rhymen/go-whatsapp"
 	"github.com/pkg/errors"
 )
 
 const (
-	loginWaitTimeSeconds = 3
-	clientTimeout        = 5
+	qrLoginWaitTimeSeconds = 3
+	clientTimeout          = 5
 )
 
 // whatsappClient abstracts go-whatsapp for writing unit tests
 type whatsappClient interface {
+	Login(qrChan chan<- string) (whatsapp.Session, error)
+	RestoreWithSession(session whatsapp.Session) (whatsapp.Session, error)
 	Send(msg interface{}) (string, error)
 }
 
@@ -34,13 +36,6 @@ func New() (*Service, error) {
 		return nil, err
 	}
 
-	err = login(client)
-	if err != nil {
-		return nil, err
-	}
-
-	<-time.After(loginWaitTimeSeconds * time.Second)
-
 	s := &Service{
 		client:   client,
 		contacts: []string{},
@@ -48,12 +43,37 @@ func New() (*Service, error) {
 	return s, nil
 }
 
-// login helps with the WhatsApp authentication process.
+// LoginWithSessionCredentials provides helper for authentication using whatsapp.Session credentials.
+func (s *Service) LoginWithSessionCredentials(clientID, clientToken, serverToken, wid string, encKey, macKey []byte) error {
+	session := whatsapp.Session{
+		ClientId:    clientID,
+		ClientToken: clientToken,
+		ServerToken: serverToken,
+		Wid:         wid,
+		EncKey:      encKey,
+		MacKey:      macKey,
+	}
+
+	session, err := s.client.RestoreWithSession(session)
+	if err != nil {
+		return fmt.Errorf("restoring session failed: %v", err)
+	}
+
+	// Save the updated session for future use without login.
+	err = writeSession(&session)
+	if err != nil {
+		return fmt.Errorf("error saving session: %v", err)
+	}
+
+	return nil
+}
+
+// LoginWithQRCode provides helper for authentication using QR code on terminal.
 // Refer: https://github.com/Rhymen/go-whatsapp#login for more information.
-func login(client *whatsapp.Conn) error {
+func (s *Service) LoginWithQRCode() error {
 	session, err := readSession()
 	if err == nil {
-		session, err = client.RestoreWithSession(session)
+		session, err = s.client.RestoreWithSession(session)
 		if err != nil {
 			return fmt.Errorf("restoring session failed: %v", err)
 		}
@@ -65,7 +85,7 @@ func login(client *whatsapp.Conn) error {
 			terminal.Get(<-qr).Print()
 		}()
 
-		session, err = client.Login(qr)
+		session, err = s.client.Login(qr)
 		if err != nil {
 			return fmt.Errorf("error during login: %v", err)
 		}
@@ -76,6 +96,8 @@ func login(client *whatsapp.Conn) error {
 		return fmt.Errorf("error saving session: %v", err)
 	}
 
+	<-time.After(qrLoginWaitTimeSeconds * time.Second)
+
 	return nil
 }
 

service/whatsapp/whatsapp_test.go

@@ -3,7 +3,7 @@ package whatsapp
 import (
 	"testing"
 
-	whatsapp "github.com/Rhymen/go-whatsapp"
+	"github.com/Rhymen/go-whatsapp"
 	"github.com/pkg/errors"
 	"github.com/stretchr/testify/require"
 )