将数据添加到 python 中的 json dict

Question

hi im importing multiple json files

and i want to add current time to each doc of the file i tried this:

for filename in os.listdir(directory):
    if filename.endswith(".json"):
        f = open(filename)
        data = json.loads(f.read())
        for i in range (len(data)):
            print(data[i])
            data[i].append({'Date':datetime.now()})
            print(data[i])

i got this:( AttributeError: 'dict' object has no attribute 'append') because it's not a list

Here is what data looks like (my json file content):

[{'trimestre': '2',
  'season': 'spring'},
 {'trimestre': '2',
  'season': 'spring'}]

and i want it to look like

[{'date': '2021-06-02T12:18:22.694+02:00',
  'trimestre': '2',
  'season': 'spring'},
 {'date': '2021-06-02T12:18:22.694+02:00',
  'trimestre': '2',
  'season': 'spring'}]

With date=current time Any help?

Answer 1

First, your answer: The only line you have to change is the one with the assignment. Like the answer above is also mentioning, the assignment has to be changed, like that:

dictionary[key] = datetime.now()

However, JSON can't store a datetime object, which is why you will have to change the format. I would therefore advise you to use strftime():

dictionary[key] = datetime.now().strftime("%d/%m/%y")

You can change the format to the one you want.

PS: The JSON format actually uses these {} brackets for the outer one. You are using a list, which is not common.

Answer 2

To add a key value pair to a dict this is the syntax:

    adict[key] = value

unrelated to the question but its safer to use with open when handling files

    with open(filename) as json_file:
        data = json.load(json_file)
        # data contains a list of dicts
        for json_dict in data:
            json_dict['Date'] = datetime.now()