add a pdf generator for invoices

server/app/admin_handler.go

@@ -559,7 +559,7 @@ func (a *App) CreateNewAnnouncementHandler(req *http.Request) (interface{}, Resp
 	for _, user := range users {
 		subject, body := internal.AdminAnnouncementMailContent(adminAnnouncement.Subject, adminAnnouncement.Body, a.config.Server.Host, user.Name())
 
-		err = internal.SendMail(a.config.MailSender.Email, a.config.MailSender.SendGridKey, user.Email, subject, body)
+		err = a.mailer.SendMail(a.config.MailSender.Email, user.Email, subject, body)
 		if err != nil {
 			log.Error().Err(err).Send()
 			return nil, InternalServerError(errors.New(internalServerErrorMsg))
@@ -621,7 +621,7 @@ func (a *App) SendEmailHandler(req *http.Request) (interface{}, Response) {
 
 	subject, body := internal.AdminMailContent(fmt.Sprintf("Hey! 📢 %s", emailUser.Subject), emailUser.Body, a.config.Server.Host, user.Name())
 
-	err = internal.SendMail(a.config.MailSender.Email, a.config.MailSender.SendGridKey, user.Email, subject, body)
+	err = a.mailer.SendMail(a.config.MailSender.Email, user.Email, subject, body)
 	if err != nil {
 		log.Error().Err(err).Send()
 		return nil, InternalServerError(errors.New(internalServerErrorMsg))
@@ -699,7 +699,7 @@ func (a *App) notifyAdmins() {
 			subject, body := internal.NotifyAdminsMailContent(len(pending), a.config.Server.Host)
 
 			for _, admin := range admins {
-				err = internal.SendMail(a.config.MailSender.Email, a.config.MailSender.SendGridKey, admin.Email, subject, body)
+				err = a.mailer.SendMail(a.config.MailSender.Email, admin.Email, subject, body)
 				if err != nil {
 					log.Error().Err(err).Send()
 				}
@@ -716,7 +716,7 @@ func (a *App) notifyAdmins() {
 			subject, body := internal.NotifyAdminsMailLowBalanceContent(balance, a.config.Server.Host)
 
 			for _, admin := range admins {
-				err = internal.SendMail(a.config.MailSender.Email, a.config.MailSender.SendGridKey, admin.Email, subject, body)
+				err = a.mailer.SendMail(a.config.MailSender.Email, admin.Email, subject, body)
 				if err != nil {
 					log.Error().Err(err).Send()
 				}

server/app/app.go

@@ -26,6 +26,7 @@ type App struct {
 	db       models.DB
 	redis    streams.RedisClient
 	deployer c4sDeployer.Deployer
+	mailer   internal.Mailer
 }
 
 // NewApp creates new server app all configurations
@@ -73,6 +74,7 @@ func NewApp(ctx context.Context, configFile string) (app *App, err error) {
 		db:       db,
 		redis:    redis,
 		deployer: newDeployer,
+		mailer:   internal.NewMailer(config.MailSender.SendGridKey),
 	}, nil
 }
 
@@ -156,6 +158,7 @@ func (a *App) registerHandlers() {
 
 	invoiceRouter.HandleFunc("", WrapFunc(a.ListInvoicesHandler)).Methods("GET", "OPTIONS")
 	invoiceRouter.HandleFunc("/{id}", WrapFunc(a.GetInvoiceHandler)).Methods("GET", "OPTIONS")
+	invoiceRouter.HandleFunc("/download/{id}", WrapFunc(a.DownloadInvoiceHandler)).Methods("GET", "OPTIONS")
 	invoiceRouter.HandleFunc("/pay/{id}", WrapFunc(a.PayInvoiceHandler)).Methods("PUT", "OPTIONS")
 
 	notificationRouter.HandleFunc("", WrapFunc(a.ListNotificationsHandler)).Methods("GET", "OPTIONS")

server/app/invoice_handler.go

@@ -119,6 +119,72 @@ func (a *App) GetInvoiceHandler(req *http.Request) (interface{}, Response) {
 	}, Ok()
 }
 
+// DownloadInvoiceHandler downloads user's invoice by ID
+// Example endpoint: Downloads user's invoice by ID
+// @Summary Downloads user's invoice by ID
+// @Description Downloads user's invoice by ID
+// @Tags Invoice
+// @Accept  json
+// @Produce  json
+// @Security BearerAuth
+// @Param id path string true "Invoice ID"
+// @Success 200 {object} Response
+// @Failure 400 {object} Response
+// @Failure 401 {object} Response
+// @Failure 404 {object} Response
+// @Failure 500 {object} Response
+// @Router /invoice/download/{id} [get]
+func (a *App) DownloadInvoiceHandler(req *http.Request) (interface{}, Response) {
+	userID := req.Context().Value(middlewares.UserIDKey("UserID")).(string)
+
+	id, err := strconv.Atoi(mux.Vars(req)["id"])
+	if err != nil {
+		log.Error().Err(err).Send()
+		return nil, BadRequest(errors.New("failed to read invoice id"))
+	}
+
+	invoice, err := a.db.GetInvoice(id)
+	if err == gorm.ErrRecordNotFound {
+		return nil, NotFound(errors.New("invoice is not found"))
+	}
+	if err != nil {
+		log.Error().Err(err).Send()
+		return nil, InternalServerError(errors.New(internalServerErrorMsg))
+	}
+
+	// Creating pdf for invoice if it doesn't have it
+	if len(invoice.FileData) == 0 {
+		user, err := a.db.GetUserByID(userID)
+		if err == gorm.ErrRecordNotFound {
+			return nil, NotFound(errors.New("user is not found"))
+		}
+		if err != nil {
+			log.Error().Err(err).Send()
+			return nil, InternalServerError(errors.New(internalServerErrorMsg))
+		}
+
+		pdfContent, err := internal.CreateInvoicePDF(invoice, user, a.config.InvoiceLogoPath)
+		if err != nil {
+			log.Error().Err(err).Send()
+			return nil, InternalServerError(errors.New(internalServerErrorMsg))
+		}
+
+		invoice.FileData = pdfContent
+		if err := a.db.UpdateInvoicePDF(id, invoice.FileData); err != nil {
+			log.Error().Err(err).Send()
+			return nil, InternalServerError(errors.New(internalServerErrorMsg))
+		}
+	}
+
+	if userID != invoice.UserID {
+		return nil, NotFound(errors.New("invoice is not found"))
+	}
+
+	return invoice.FileData, Ok().
+		WithHeader("Content-Disposition", fmt.Sprintf("attachment; filename=%s", fmt.Sprintf("invoice-%s-%d.pdf", invoice.UserID, invoice.ID))).
+		WithHeader("Content-Type", "application/pdf")
+}
+
 // PayInvoiceHandler pay user's invoice
 // Example endpoint: Pay user's invoice
 // @Summary Pay user's invoice
@@ -213,7 +279,7 @@ func (a *App) monthlyInvoices() {
 		// Create invoices for all system users
 		for _, user := range users {
 			// 1. Create new monthly invoice
-			if err = a.createInvoice(user.ID.String(), now); err != nil {
+			if err = a.createInvoice(user, now); err != nil {
 				log.Error().Err(err).Send()
 			}
 
@@ -275,15 +341,15 @@ func (a *App) monthlyInvoices() {
 	}
 }
 
-func (a *App) createInvoice(userID string, now time.Time) error {
+func (a *App) createInvoice(user models.User, now time.Time) error {
 	monthStart := time.Date(now.Year(), now.Month(), 0, 0, 0, 0, 0, time.Local)
 
-	vms, err := a.db.GetAllSuccessfulVms(userID)
+	vms, err := a.db.GetAllSuccessfulVms(user.ID.String())
 	if err != nil && err != gorm.ErrRecordNotFound {
 		return err
 	}
 
-	k8s, err := a.db.GetAllSuccessfulK8s(userID)
+	k8s, err := a.db.GetAllSuccessfulK8s(user.ID.String())
 	if err != nil && err != gorm.ErrRecordNotFound {
 		return err
 	}
@@ -308,6 +374,8 @@ func (a *App) createInvoice(userID string, now time.Time) error {
 			DeploymentResources: vm.Resources,
 			DeploymentType:      "vm",
 			DeploymentID:        vm.ID,
+			DeploymentName:      vm.Name,
+			DeploymentCreatedAt: vm.CreatedAt,
 			HasPublicIP:         vm.Public,
 			PeriodInHours:       time.Since(usageStart).Hours(),
 			Cost:                cost,
@@ -333,6 +401,8 @@ func (a *App) createInvoice(userID string, now time.Time) error {
 			DeploymentResources: cluster.Master.Resources,
 			DeploymentType:      "k8s",
 			DeploymentID:        cluster.ID,
+			DeploymentName:      cluster.Master.Name,
+			DeploymentCreatedAt: cluster.CreatedAt,
 			HasPublicIP:         cluster.Master.Public,
 			PeriodInHours:       time.Since(usageStart).Hours(),
 			Cost:                cost,
@@ -342,11 +412,22 @@ func (a *App) createInvoice(userID string, now time.Time) error {
 	}
 
 	if len(items) > 0 {
-		if err = a.db.CreateInvoice(&models.Invoice{
-			UserID:      userID,
+		in := models.Invoice{
+			UserID:      user.ID.String(),
 			Total:       total,
 			Deployments: items,
-		}); err != nil {
+		}
+
+		// Creating pdf for invoice
+		pdfContent, err := internal.CreateInvoicePDF(in, user, a.config.InvoiceLogoPath)
+		if err != nil {
+			return err
+		}
+
+		in.FileData = pdfContent
+
+		// Creating invoice in db
+		if err = a.db.CreateInvoice(&in); err != nil {
 			return err
 		}
 	}
@@ -415,14 +496,14 @@ func (a *App) sendInvoiceReminderToUser(userID, userEmail, userName string, now
 	}
 
 	for _, invoice := range invoices {
-		oneMonthsAgo := now.AddDate(0, -1, 0)
+		// oneMonthsAgo := now.AddDate(0, -1, 0)
 		oneWeekAgo := now.AddDate(0, 0, -7)
 
 		// check if the invoice created 1 months ago (not after it) and
-		// last remainder sent for this invoice was 7 days ago and
+		// last remainder sent for this invoice was before 7 days ago and
 		// invoice is not paid
-		if invoice.CreatedAt.Before(oneMonthsAgo) &&
-			invoice.LastReminderAt.Before(oneWeekAgo) &&
+		// invoice.CreatedAt.Before(oneMonthsAgo) &&
+		if invoice.LastReminderAt.Before(oneWeekAgo) &&
 			!invoice.Paid {
 			// overdue date starts after one month since invoice creation
 			overDueStart := invoice.CreatedAt.AddDate(0, 1, 0)
@@ -434,20 +515,27 @@ func (a *App) sendInvoiceReminderToUser(userID, userEmail, userName string, now
 
 			mailBody := "We hope this message finds you well.\n"
 			mailBody += fmt.Sprintf("Our records show that there is an outstanding invoice for %v %s associated with your account (%d). ", invoice.Total, currencyName, invoice.ID)
-			mailBody += fmt.Sprintf("As of today, the payment for this invoice is %d days overdue.", overDueDays)
+			if overDueDays > 0 {
+				mailBody += fmt.Sprintf("As of today, the payment for this invoice is %d days overdue.", overDueDays)
+			}
 			mailBody += "To avoid any interruptions to your services and the potential deletion of your deployments, "
 			mailBody += fmt.Sprintf("we kindly ask that you make the payment within the next %d days. If the invoice remains unpaid after this period, ", gracePeriod)
 			mailBody += "please be advised that the associated deployments will be deleted from our system.\n\n"
 
 			mailBody += "You can easily pay your invoice by charging balance, activating voucher or using cards.\n\n"
 			mailBody += "If you have already made the payment or need any assistance, "
 			mailBody += "please don't hesitate to reach out to us.\n\n"
-			mailBody += "We appreciate your prompt attention to this matter and thank you fosr being a valued customer."
+			mailBody += "We appreciate your prompt attention to this matter and thank you for being a valued customer."
 
 			subject := "Unpaid Invoice Notification – Action Required"
 			subject, body := internal.AdminMailContent(subject, mailBody, a.config.Server.Host, userName)
 
-			if err = internal.SendMail(a.config.MailSender.Email, a.config.MailSender.SendGridKey, userEmail, subject, body); err != nil {
+			if err = a.mailer.SendMail(
+				a.config.MailSender.Email, userEmail, subject, body, internal.Attachment{
+					FileName: fmt.Sprintf("invoice-%s-%d.pdf", invoice.UserID, invoice.ID),
+					Data:     invoice.FileData,
+				},
+			); err != nil {
 				log.Error().Err(err).Send()
 			}
 

server/app/payments_handler.go

@@ -349,6 +349,8 @@ func (a *App) DeleteCardHandler(req *http.Request) (interface{}, Response) {
 		return nil, BadRequest(errors.New("you have active deployment and cannot delete the card"))
 	}
 
+	// TODO: deleting vms before the end of the month then deleting all cards case
+
 	// Update the default payment method for future payments (if deleted card is the default)
 	if card.PaymentMethodID == user.StripeDefaultPaymentID {
 		var newPaymentMethod string

server/app/setup.go

@@ -76,7 +76,9 @@ func SetUp(t testing.TB) *App {
 		"medium_vm": 20,
 		"large_vm": 30
 	},
-	"stripe_secret": "sk_test"
+	"stripe_secret": "sk_test",
+	"voucher_balance": 10,
+	"invoice_logo": "server/internal/img/logo.png"
 }
 	`, dbPath)
 
@@ -105,6 +107,7 @@ func SetUp(t testing.TB) *App {
 		db:       db,
 		redis:    streams.RedisClient{},
 		deployer: newDeployer,
+		mailer:   internal.NewMailer(configuration.MailSender.SendGridKey),
 	}
 
 	return app

server/app/user_handler.go

@@ -65,8 +65,7 @@ type EmailInput struct {
 
 // ApplyForVoucherInput struct for user to apply for voucher
 type ApplyForVoucherInput struct {
-	Balance uint64 `json:"balance" binding:"required" validate:"min=0"`
-	Reason  string `json:"reason" binding:"required" validate:"nonzero"`
+	Reason string `json:"reason" binding:"required" validate:"nonzero"`
 }
 
 // AddVoucherInput struct for voucher applied by user
@@ -145,7 +144,7 @@ func (a *App) SignUpHandler(req *http.Request) (interface{}, Response) {
 	// send verification code if user is not verified or not exist
 	code := internal.GenerateRandomCode()
 	subject, body := internal.SignUpMailContent(code, a.config.MailSender.Timeout, fmt.Sprintf("%s %s", signUp.FirstName, signUp.LastName), a.config.Server.Host)
-	err = internal.SendMail(a.config.MailSender.Email, a.config.MailSender.SendGridKey, signUp.Email, subject, body)
+	err = a.mailer.SendMail(a.config.MailSender.Email, signUp.Email, subject, body)
 	if err != nil {
 		log.Error().Err(err).Send()
 		return nil, InternalServerError(errors.New(internalServerErrorMsg))
@@ -245,7 +244,7 @@ func (a *App) VerifySignUpCodeHandler(req *http.Request) (interface{}, Response)
 	middlewares.UserCreations.WithLabelValues(user.ID.String(), user.Email).Inc()
 
 	subject, body := internal.WelcomeMailContent(user.Name(), a.config.Server.Host)
-	err = internal.SendMail(a.config.MailSender.Email, a.config.MailSender.SendGridKey, user.Email, subject, body)
+	err = a.mailer.SendMail(a.config.MailSender.Email, user.Email, subject, body)
 	if err != nil {
 		log.Error().Err(err).Send()
 		return nil, InternalServerError(errors.New(internalServerErrorMsg))
@@ -405,7 +404,7 @@ func (a *App) ForgotPasswordHandler(req *http.Request) (interface{}, Response) {
 	// send verification code
 	code := internal.GenerateRandomCode()
 	subject, body := internal.ResetPasswordMailContent(code, a.config.MailSender.Timeout, user.Name(), a.config.Server.Host)
-	err = internal.SendMail(a.config.MailSender.Email, a.config.MailSender.SendGridKey, email.Email, subject, body)
+	err = a.mailer.SendMail(a.config.MailSender.Email, email.Email, subject, body)
 
 	if err != nil {
 		log.Error().Err(err).Send()
@@ -711,7 +710,7 @@ func (a *App) ApplyForVoucherHandler(req *http.Request) (interface{}, Response)
 	voucher := models.Voucher{
 		Voucher: v,
 		UserID:  userID,
-		Balance: input.Balance,
+		Balance: a.config.VoucherBalance,
 		Reason:  input.Reason,
 	}
 
@@ -840,7 +839,6 @@ func (a *App) ActivateVoucherHandler(req *http.Request) (interface{}, Response)
 // @Failure 500 {object} Response
 // @Router /user/charge_balance [put]
 func (a *App) ChargeBalance(req *http.Request) (interface{}, Response) {
-
 	userID := req.Context().Value(middlewares.UserIDKey("UserID")).(string)
 
 	var input ChargeBalance
@@ -919,6 +917,7 @@ func (a *App) ChargeBalance(req *http.Request) (interface{}, Response) {
 // @Failure 500 {object} Response
 // @Router /user [delete]
 func (a *App) DeleteUserHandler(req *http.Request) (interface{}, Response) {
+	// TODO: delete customer from stripe
 	userID := req.Context().Value(middlewares.UserIDKey("UserID")).(string)
 	user, err := a.db.GetUserByID(userID)
 	if err == gorm.ErrRecordNotFound {
@@ -930,7 +929,7 @@ func (a *App) DeleteUserHandler(req *http.Request) (interface{}, Response) {
 	}
 
 	// 1. Create last invoice to pay if there were active deployments
-	if err := a.createInvoice(userID, time.Now()); err != nil {
+	if err := a.createInvoice(user, time.Now()); err != nil {
 		log.Error().Err(err).Send()
 		return nil, InternalServerError(errors.New(internalServerErrorMsg))
 	}

server/app/user_handler_test.go

@@ -870,8 +870,6 @@ func TestApplyForVoucherHandler(t *testing.T) {
 	assert.NoError(t, err)
 
 	voucherBody := []byte(`{
-		"vms":10,
-		"public_ips":1,
 		"reason":"strongReason"
 	}`)
 

server/app/voucher_handler.go

@@ -176,7 +176,7 @@ func (a *App) UpdateVoucherHandler(req *http.Request) (interface{}, Response) {
 		subject, body = internal.RejectedVoucherMailContent(user.Name(), a.config.Server.Host)
 	}
 
-	err = internal.SendMail(a.config.MailSender.Email, a.config.MailSender.SendGridKey, user.Email, subject, body)
+	err = a.mailer.SendMail(a.config.MailSender.Email, user.Email, subject, body)
 	if err != nil {
 		log.Error().Err(err).Send()
 		return nil, InternalServerError(errors.New(internalServerErrorMsg))
@@ -228,7 +228,7 @@ func (a *App) ApproveAllVouchersHandler(req *http.Request) (interface{}, Respons
 		}
 
 		subject, body := internal.ApprovedVoucherMailContent(v.Voucher, user.Name(), a.config.Server.Host)
-		err = internal.SendMail(a.config.MailSender.Email, a.config.MailSender.SendGridKey, user.Email, subject, body)
+		err = a.mailer.SendMail(a.config.MailSender.Email, user.Email, subject, body)
 		if err != nil {
 			log.Error().Err(err).Send()
 			return nil, InternalServerError(errors.New(internalServerErrorMsg))

server/app/wrapper.go

@@ -69,7 +69,11 @@ func WrapFunc(a Handler) http.HandlerFunc {
 			status = result.Status()
 		}
 
-		if err := json.NewEncoder(w).Encode(object); err != nil {
+		if bytes, ok := object.([]byte); ok {
+			if _, err := w.Write(bytes); err != nil {
+				log.Error().Err(err).Msg("failed to write return object")
+			}
+		} else if err := json.NewEncoder(w).Encode(object); err != nil {
 			log.Error().Err(err).Msg("failed to encode return object")
 		}
 		middlewares.Requests.WithLabelValues(r.Method, r.RequestURI, fmt.Sprint(status)).Inc()