func setFrom(mail *sendgrid.SGMail, event *Event) (*sendgrid.SGMail, error) {
from, ok := event.Properties["from"]
if !ok {
from = DefaultFromAddress
}
if err := mail.SetFrom(from.(string)); err != nil {
return nil, err
}
fromName, ok := event.Properties["fromName"]
if !ok {
fromName = DefaultFromName
}
mail.SetFromName(fromName.(string))
return mail, nil
}
