[MM-29845] Add CWS Webhook endpoint and payment failed email (#16351)

* Add a new handler to allow authentication via CWS API Key

* Make error better

* Add tests and cases for new handler functions

* Move some code around

* Add test for GetCloudSession function

* unset the env after test completion

* Remove white space

* Add CWS Webhook endpoint and email code

* handle returned errors from email sending function

* Change FailureCode to FailureMessage

* Remove unnecessary translations

* Fix translations

* Forgot to add template

* Update api4/cloud.go

Co-authored-by: Maria A Nunez <maria.nunez@mattermost.com>

* Update api4/cloud.go

Co-authored-by: Maria A Nunez <maria.nunez@mattermost.com>

* Update api4/cloud.go

Co-authored-by: Maria A Nunez <maria.nunez@mattermost.com>

* PR changes

* Update app/email.go

Co-authored-by: Mario de Frutos Dieguez <mario@defrutos.org>

* Close body in proper spot

Co-authored-by: Mattermod <mattermod@users.noreply.github.com>
Co-authored-by: Maria A Nunez <maria.nunez@mattermost.com>
Co-authored-by: Mario de Frutos Dieguez <mario@defrutos.org>

app/cloud.go

@@ -4,9 +4,20 @@
 package app
 
 import (
+	"github.com/mattermost/mattermost-server/v5/mlog"
 	"github.com/mattermost/mattermost-server/v5/model"
 )
 
+func (a *App) getSysAdminsEmailRecipients() ([]*model.User, *model.AppError) {
+	userOptions := &model.UserGetOptions{
+		Page:     0,
+		PerPage:  100,
+		Role:     model.SYSTEM_ADMIN_ROLE_ID,
+		Inactive: false,
+	}
+	return a.GetUsers(userOptions)
+}
+
 func (a *App) CheckAndSendUserLimitWarningEmails() *model.AppError {
 	if a.Srv().License() == nil || (a.Srv().License() != nil && !*a.Srv().License().Features.Cloud) {
 		// Not cloud instance, do nothing
@@ -30,13 +41,7 @@ func (a *App) CheckAndSendUserLimitWarningEmails() *model.AppError {
 	if remainingUsers > 0 {
 		return nil
 	}
-	userOptions := &model.UserGetOptions{
-		Page:     0,
-		PerPage:  100,
-		Role:     model.SYSTEM_ADMIN_ROLE_ID,
-		Inactive: false,
-	}
-	sysAdmins, err := a.GetUsers(userOptions)
+	sysAdmins, err := a.getSysAdminsEmailRecipients()
 	if err != nil {
 		return err
 	}
@@ -55,3 +60,18 @@ func (a *App) CheckAndSendUserLimitWarningEmails() *model.AppError {
 	}
 	return nil
 }
+
+func (a *App) SendPaymentFailedEmail(failedPayment *model.FailedPayment) *model.AppError {
+	sysAdmins, err := a.getSysAdminsEmailRecipients()
+	if err != nil {
+		return err
+	}
+
+	for _, admin := range sysAdmins {
+		_, err := a.Srv().EmailService.SendPaymentFailedEmail(admin.Email, admin.Locale, failedPayment, *a.Config().ServiceSettings.SiteURL)
+		if err != nil {
+			a.Log().Error("Error sending payment failed email", mlog.Err(err))
+		}
+	}
+	return nil
+}