Django python：如何從Django queryset制作json

Question

我有查詢集，它在轉換后的列表后返回一個json字符串。

[{"pid": 1, "loc": "KL", "sid": 1, "sd": "south-1"},
 {"pid": 1, "loc": "KL", "sid": 2, "sd": "north-5"},    
 {"pid": 1, "loc": "KL", "sid": 3, "sd": "west-3"}
]

我已經嘗試了許多序列化器選項，但不知道如何使上述內容成為：

[{"pid": 1,
  "s": [{"sid": 1, "sd": "south-1",
         "sid": 2, "sd": "north-5",
         "sid": 3, "sd": "west-3"
       }]
}]

Answer 1

首先，您的預期輸出中有錯誤。 您可能的意思是：

[{"pid": 1,
  "s": [{"sid": 1, "sd": "south-1"},
        {"sid": 2, "sd": "north-5"},
        {"sid": 3, "sd": "west-3"}
       ],
  "loc": "KL"
}]

即s應該是字典列表，而不是一個字典（和沖突鍵）。 我添加了"loc": "KL"因為它似乎丟失了。

假設每個查詢只返回相同的pid和loc ，你可以創建s與每個列表sid和sd在原來的查詢：

>>> q = ... # as above
>>> r = {"pid": q[0]["pid"], "loc": q[0]["loc"]}  # since pid and loc are always the same
>>> r["s"] = [{"sid": x["sid"], "sd": x["sd"]} for x in q]
>>> print r
[{'pid': 1,
  's': [{'sid': 1, 'sd': 'south-1'},
        {'sid': 2, 'sd': 'north-5'},
        {'sid': 3, 'sd': 'west-3'}
       ],
  'loc': 'KL'
}]
>>> print json.dumps(r)  # gives the output as a json string