public virtual ICollection <MongoDbDatabase> GetMongoDatabases()
 {
     try
     {
         var webConfigDocument = GetWebConfigResult();
         var webRootPath       = Instance.WebRootPath;
         return(WebConfig.GetMongoDatabases(webRootPath, webConfigDocument));
     }
     catch (Exception ex)
     {
         throw new InvalidOperationException($"Failed to get mongo databases of {Instance.WebRootPath}", ex);
     }
 }