set 类型的对象不是 JSON 可序列化的

Question

我正在尝试将以下列表传递给 ajax 响应，但我遇到了错误

remove_duplicates = [{**l[0], 'record_id': set([x['record_id'] for x in l])} if len(l:=list(v)) > 1 else l[0] for _, v in groupby(sorted(list_of_dict, key=func), key=func)]

我正在使用 set 删除重复的记录 ID

list_of_dicts = [{'f_note':'text','record_id':{4691}},{'f_note':'sample','record_id':{4692}}]

return jsonify(list_of_dicts )

set 类型的对象不是 JSON 可序列化的

请给我建议更好的选择。

Answer 1

当您创建字典列表时，您的 {4691} 的内部值实际上是一个集合而不是一个字典。

https://realpython.com/python-sets/

试试这个：

list_of_dicts = [{'f_note':'text','record_id': 4691},{'f_note':'sample','record_id': 4692}]

return jsonify(list_of_dicts)

查看您遇到的孤立错误

import json
test = {5565}

json.dumps(test)

Traceback (most recent call last):
  File "<input>", line 1, in <module>
  File "C:\Users\p\AppData\Local\Programs\Python\Python39\lib\json\__init__.py", line 231, in dumps
    return _default_encoder.encode(obj)
  File "C:\Users\p\AppData\Local\Programs\Python\Python39\lib\json\encoder.py", line 199, in encode
    chunks = self.iterencode(o, _one_shot=True)
  File "C:\Users\p\AppData\Local\Programs\Python\Python39\lib\json\encoder.py", line 257, in iterencode
    return _iterencode(o, 0)
  File "C:\Users\p\AppData\Local\Programs\Python\Python39\lib\json\encoder.py", line 179, in default
    raise TypeError(f'Object of type {o.__class__.__name__} '
TypeError: Object of type set is not JSON serializable

要保留设置的功能，您可以将其转换回列表

remove_duplicates = [{**l[0], 'record_id': list(set([x['record_id'] for x in l]))} if len(l:=list(v)) > 1 else l[0] for _, v in groupby(sorted(list_of_dict, key=func), key=func)]