來源格式與預期記錄
這是原創假設轉換例子。輸入限下列欄位的普通、無循環 JSON 形記錄,統一記錄格式及拒絕代碼由本例訂明。若換來源,先修改格式約定。
本例路徑以點分層,各段用小寫字母及數字、字母開頭,不容 constructor、prototype。葉值可為文字、布林、有限數字或 null。按路徑建立巢狀物件;同一位置既要放葉值又要作物件,無論插入先後都拒絕。
| 個案 | 輸入記錄(JSON) | 預期輸出(JSON) |
|---|---|---|
| 按欄位路徑建物件 | {"fields":{"person.name":"Ada","address.city":"Demo"}} | {"ok":true,"value":{"record":{"person":{"name":"Ada"},"address":{"city":"Demo"}}}} |
| 拒絕值與容器衝突 | {"fields":{"person":"Ada","person.name":"Bo"}} | {"ok":false,"error":"PATH_CONFLICT"} |
| 保留明確空值 | {"fields":{"request.note":null}} | {"ok":true,"value":{"record":{"request":{"note":null}}}} |
在本機執行轉換
把完整例子以 JavaScript 模組在 Node.js 執行,內含純轉換函數、三個輸入及寫明的預期輸出,對不上便由斷言停止。拒絕個案回傳 ok=false 及代碼,不回傳半份統一記錄。
import assert from 'node:assert/strict';
function flatPaths(i){
const fail=error=>({ok:false,error});if(!i||!i.fields||typeof i.fields!=='object'||Array.isArray(i.fields))return fail('PATH_FIELDS');
const record={};const scalar=v=>v===null||typeof v==='string'||typeof v==='boolean'||(typeof v==='number'&&Number.isFinite(v));
for(const [path,value]of Object.entries(i.fields)){
const pieces=path.split('.');
if(!pieces.every(p=>/^[a-z][a-z0-9]*$/.test(p)&&!['constructor','prototype'].includes(p)))return fail('PATH_NAME');
if(!scalar(value))return fail('PATH_VALUE');let at=record;
for(let n=0;n<pieces.length;n++){
const key=pieces[n];
if(n===pieces.length-1){if(Object.hasOwn(at,key))return fail('PATH_CONFLICT');at[key]=value;}
else{
if(Object.hasOwn(at,key)){if(!at[key]||typeof at[key]!=='object'||Array.isArray(at[key]))return fail('PATH_CONFLICT');}
else at[key]={};at=at[key];
}
}
}
return {ok:true,value:{record}};
}
// Original synthetic cases; expected outputs are literal records.
const cases = [
{
"label": "Build objects from field paths",
"input": {
"fields": {
"person.name": "Ada",
"address.city": "Demo"
}
},
"expected": {
"ok": true,
"value": {
"record": {
"person": {
"name": "Ada"
},
"address": {
"city": "Demo"
}
}
}
}
},
{
"label": "Reject leaf/container conflict",
"input": {
"fields": {
"person": "Ada",
"person.name": "Bo"
}
},
"expected": {
"ok": false,
"error": "PATH_CONFLICT"
}
},
{
"label": "Preserve explicit null leaf",
"input": {
"fields": {
"request.note": null
}
},
"expected": {
"ok": true,
"value": {
"record": {
"request": {
"note": null
}
}
}
}
}
];
for (const sample of cases) {
const actual = flatPaths(sample.input);
assert.deepEqual(actual, sample.expected);
console.log(sample.label, JSON.stringify(actual));
}
判清邊界個案
person="Ada" 可否與 person.name="Bo" 並存?
查看參考答案
不可。person 不能同時是文字葉值及物件容器,回傳 PATH_CONFLICT。獨立的 request.note=null 則是有效明確葉值。