// POST api/values
 public bool Post([FromBody] DataAccess.UserSchema value)
 {
     try
     {
         var ctx   = new DataAccess.GraphKnowledgeEntities();
         var model = ctx.UserSchemas.Add(new DataAccess.UserSchema
         {
             OwnerUserId = value.OwnerUserId,
             SchemaName  = value.SchemaName,
             SchemaDesc  = value.SchemaDesc
         });
         ctx.SaveChanges();
         //if (!File.Exists(System.Web.HttpContext.Current.Server.MapPath($"~/Content/graph{DateTime.Now.ToString("yyyyMMdd")}.json")))
         //{
         //    File.WriteAllText(System.Web.HttpContext.Current.Server.MapPath($"~/Content/graph{DateTime.Now.ToString("yyyyMMdd")}.json"), File.ReadAllText(System.Web.HttpContext.Current.Server.MapPath("~/Content/graph.json")));
         //}
         //File.WriteAllText(System.Web.HttpContext.Current.Server.MapPath("~/Content/graph.json"), value);
         return(true);
     }
     catch (Exception e)
     {
     }
     return(false);
 }