feat: example of multiple sessions

.gitignore

@@ -0,0 +1 @@
+.idea/

client_test.go

@@ -9,43 +9,51 @@ package whatsmeow_test
 import (
 	"context"
 	"fmt"
+	"go.mau.fi/whatsmeow/store"
+	"go.mau.fi/whatsmeow/types"
 	"os"
 	"os/signal"
 	"syscall"
+	"time"
 
 	"go.mau.fi/whatsmeow"
 	"go.mau.fi/whatsmeow/store/sqlstore"
 	"go.mau.fi/whatsmeow/types/events"
 	waLog "go.mau.fi/whatsmeow/util/log"
 )
 
+// For single and multiple sessions
+
+var container *sqlstore.Container
+var dbLog waLog.Logger
+var clientLog waLog.Logger
+
 func eventHandler(evt interface{}) {
 	switch v := evt.(type) {
 	case *events.Message:
 		fmt.Println("Received a message!", v.Message.GetConversation())
 	}
 }
 
-func Example() {
-	dbLog := waLog.Stdout("Database", "DEBUG", true)
+func start() {
+	dbLog = waLog.Stdout("Database", "DEBUG", true)
+	var err error
 	// Make sure you add appropriate DB connector imports, e.g. github.com/mattn/go-sqlite3 for SQLite
-	container, err := sqlstore.New("sqlite3", "file:examplestore.db?_foreign_keys=on", dbLog)
+	container, err = sqlstore.New("sqlite3", "file:examplestore.db?_foreign_keys=on", dbLog)
 	if err != nil {
 		panic(err)
 	}
-	// If you want multiple sessions, remember their JIDs and use .GetDevice(jid) or .GetAllDevices() instead.
-	deviceStore, err := container.GetFirstDevice()
-	if err != nil {
-		panic(err)
-	}
-	clientLog := waLog.Stdout("Client", "DEBUG", true)
-	client := whatsmeow.NewClient(deviceStore, clientLog)
-	client.AddEventHandler(eventHandler)
+
+	clientLog = waLog.Stdout("Client", "DEBUG", true)
+}
+
+func connectClient(client *whatsmeow.Client) *types.JID {
 
 	if client.Store.ID == nil {
+
 		// No ID stored, new login
 		qrChan, _ := client.GetQRChannel(context.Background())
-		err = client.Connect()
+		err := client.Connect()
 		if err != nil {
 			panic(err)
 		}
@@ -55,22 +63,127 @@ func Example() {
 				// e.g. qrterminal.GenerateHalfBlock(evt.Code, qrterminal.L, os.Stdout)
 				// or just manually `echo 2@... | qrencode -t ansiutf8` in a terminal
 				fmt.Println("QR code:", evt.Code)
+			} else if evt.Event == "success" {
+				return client.Store.ID
 			} else {
 				fmt.Println("Login event:", evt.Event)
 			}
 		}
+
 	} else {
+
 		// Already logged in, just connect
-		err = client.Connect()
+		err := client.Connect()
 		if err != nil {
 			panic(err)
 		}
 	}
 
+	return nil
+}
+
+func getClient(deviceStore *store.Device) *whatsmeow.Client {
+
+	client := whatsmeow.NewClient(deviceStore, clientLog)
+	client.AddEventHandler(eventHandler)
+
+	return client
+}
+
+// For multiple sessions
+
+var jid1 *types.JID // This pretends to be your database
+var jid2 *types.JID // This pretends to be your database
+
+func selectJIDFromFakeDatabase(textJID string) *types.JID {
+
+	jid, err := types.ParseJID(textJID) // Fake database search
+	if err != nil {
+		panic(err)
+	}
+
+	return &jid
+}
+
+// Exemples
+
+func ExampleSigleSession() {
+
+	start()
+
+	// If you want multiple sessions, remember their JIDs and use .GetDevice(jid) or .GetAllDevices() instead.
+	deviceStore, err := container.GetFirstDevice()
+	if err != nil {
+		panic(err)
+	}
+
+	client := getClient(deviceStore)
+	connectClient(client)
+
 	// Listen to Ctrl+C (you can also do something else that prevents the program from exiting)
 	c := make(chan os.Signal)
 	signal.Notify(c, os.Interrupt, syscall.SIGTERM)
 	<-c
 
 	client.Disconnect()
 }
+
+func ExampleMultipleSessions() {
+
+	start()
+
+	// First run, adding new users / WhatsApp
+	deviceStore1 := container.NewDevice()
+	deviceStore2 := container.NewDevice()
+
+	client1 := getClient(deviceStore1)
+	client2 := getClient(deviceStore2)
+
+	jid1 = connectClient(client1) // Scanning the QR Code and saving the JID in the fake database
+	jid2 = connectClient(client2) // Scanning the QR Code and saving the JID in the fake database
+
+	// Here your system may suffer a crash, be restarted or other reasons that may require you to recover old sessions
+	fmt.Println("\n\n\n\n\n\n\n\n\n Waiting for initial sync \n\n\n\n\n\n\n\n\n ")
+	time.Sleep(30 * time.Second)
+
+	client1.Disconnect() // Ending current session to simulate reconnection
+	client2.Disconnect() // Ending current session to simulate reconnection
+
+	fmt.Println("\n\n\n\n\n\n\n\n\n Disconnected customers \n\n\n\n\n\n\n\n\n ")
+	time.Sleep(10 * time.Second)
+
+	fmt.Println("\n\n\n\n\n\n\n\n\n Restoring sessions \n\n\n\n\n\n\n\n\n ")
+	// Here your system is connecting again and so that you don't have to scan the QR Code again, retrieve the JIDs from your database
+	jid1 = selectJIDFromFakeDatabase(jid1.String()) // Fake JID recovery
+	jid2 = selectJIDFromFakeDatabase(jid2.String()) // Fake JID recovery
+
+	// Recreating devices and clients for new connection with old session
+	var err error
+	deviceStore1, err = container.GetDevice(*jid1)
+	if err != nil {
+		panic(err)
+	}
+
+	deviceStore2, err = container.GetDevice(*jid2)
+	if err != nil {
+		panic(err)
+	}
+
+	client1 = getClient(deviceStore1)
+	client2 = getClient(deviceStore2)
+
+	// Connecting clients with previous sessions
+
+	connectClient(client1) // Now you will only be connected to WhatsApp and will not need to scan the QR Code
+	connectClient(client2) // Now you will only be connected to WhatsApp and will not need to scan the QR Code
+
+	fmt.Println("\n\n\n\n\n\n\n\n\n Clients connected to old sessions \n\n\n\n\n\n\n\n\n ")
+
+	// Listen to Ctrl+C (you can also do something else that prevents the program from exiting)
+	c := make(chan os.Signal)
+	signal.Notify(c, os.Interrupt, syscall.SIGTERM)
+	<-c
+
+	client1.Disconnect()
+	client2.Disconnect()
+}