public async Task <IHttpActionResult> PostContactInfo(ContactInfo contactInfo)
        {
            if (!ModelState.IsValid)
            {
                return(BadRequest(ModelState));
            }

            try
            {
                await MessagingService.AddContactInfo(contactInfo);
            }
            catch (InvalidOperationException)
            {
                if (ContactInfoExists(contactInfo.ContactUsername, contactInfo.UserId))
                {
                    return(Conflict());
                }
                else
                {
                    throw;
                }
            }

            return(CreatedAtRoute("DefaultApi", new { id1 = contactInfo.ContactUsername, id2 = contactInfo.UserId }, contactInfo));
        }