设置了foreceDefaultValue{ "$env":"uid"}，为何创建记录的时候不生成

首先在schema里设置了

"reserve_userID": {  
            "forceDefaultValue": {  
                "$env": "uid"  
            },  
            "foreignKey": "uni-id-users._id",  
            "permission": {  
                "read": true,  
                "create": true,  
                "update": false,  
                "delete": false  
            },  
            "description": "用户ID"  
        },

我在前端提交相应表单数据的时候发现并没有生成该字段以及默认uid，如果我在前端主动提交reserve_userID，还会报错：

Uncaught (in promise)P: [router]: ValidationFailed:errCode: ValidationFailed | errMsg: 参数校验错误: doc field should not contain illegal character
at Function.complete (http://localhost:8081/static/js/chunk-vendors.js:13065:6053)
at http://localhost:8081/static/js/chunk-vendors.js:708:86381
at Object.I [as callback] (http://localhost:8081/static/js/chunk-vendors.js:708:89543)
at b (http://localhost:8081/static/js/chunk-vendors.js:708:90065)
at XMLHttpRequest.k.onload (http://localhost:8081/static/js/chunk-vendors.js:708:56285)