使用 json.dump 时附加日期和时间戳？

Question

您好，我目前正在以下列方式转储每帧图像矩阵的输出。我

with open(os.path.join('logs', 'frame_{0}_keypoints.json'.format(str(frame_number).zfill(12))).format(frame_dict), 'w') as outfile:
   json.dump(my_dict, outfile)

有了这个，我可以得到 json 每帧文件，格式为 frame_000000000001_keypoints ，我想知道是否有办法将时间戳附加到日志？比如20190607T220005YearMonthDayTimeinHoursMinutesSeconds??

Answer 1

我的回答假设您想为“my_dict”添加时间戳。

import json
import time


class TimeStampAdderEncoder(json.JSONEncoder):
    def encode(self, obj):
        obj['timestamp'] = time.time()
        return json.JSONEncoder().encode(obj)


my_dict = {'key': 3}
my_dict_as_str = json.dumps(my_dict, cls=TimeStampAdderEncoder)
print(my_dict_as_str)

输出

{"key": 3, "timestamp": 1561542873.109698}

Answer 2

如果您希望输出具有此格式frame_ 20190607T220005_keypoints 的 .json 文件，您可以使用：

import datetime 
now = datetime.datetime.now()   

now_isoFormat = now.isoformat() # GET - 2019-06-26T09:20:30.943730

now_custom_isoFormat = "{YEAR}{MONTH}{DAY}T{HOUR}{MINUTES}{SECONDS}".format(
    YEAR=now.year,
    MONTH=now.month,
    DAY=now.day,
    HOUR=now.hour,
    MINUTES=now.minute,
    SECONDS=now.second) # GET - 2019626T092030

with open(os.path.join('logs', 'frame_{0}_keypoints.json'.format(now_custom_isoFormat)).format(frame_dict), 'w') as outfile:
       json.dump(my_dict, outfile)

如果您希望保留帧号：

with open(os.path.join('logs', 'frame_{date}_keypoints_{frame}.json'
        .format(date=now_custom_isoFormat,
                frame=str(frame_number).zfill(12)))
                  .format(frame_dict), 'w') as outfile:
    json.dump(my_dict, outfile)