Question

我使用json.dumps将一些数据写入文件。我现在正试图使用json.load和json.loads在另一个工具中读取此数据并收到此错误：

Traceback (most recent call last):
  File "./compute_avg_cpu_util.py", line 16, in <module>
    data = json.loads(line.rstrip())
  File "/usr/local/python-2.76/lib/python2.7/json/__init__.py", line 338, in loads
    return _default_decoder.decode(s)
  File "/usr/local/python-2.76/lib/python2.7/json/decoder.py", line 365, in decode
    obj, end = self.raw_decode(s, idx=_w(s, 0).end())
  File "/usr/local/python-2.76/lib/python2.7/json/decoder.py", line 383, in raw_decode
    raise ValueError("No JSON object could be decoded")
ValueError: No JSON object could be decoded

以下是两行示例数据：

tail -2 file.dat | cat -vet

{"sample": 309896986, "data": {"value": 2}, "samples": 319049477, "startTime": "20151213T00:01:47"}    
{"sample": 309896987, "data": {"value": 2}, "samples": 319049477, "startTime": "20151213T00:01:48"}

这是我的代码（现在）：

for file in files.split(","):
    with open(file, "r") as f:
        data = None
        for line in f:
            if not line.startswith("{"):
                continue
            data = json.loads(line)

我可能通过这样做错误地写了这些数据文件（这些数据来自对存储设备的REST api调用）：

for sample in result.getdata()['data']:
    sys.stdout.write("%s\n" % json.dumps(sample))

Answer 1

1）尝试捕捉任何异常：

  try:
    data = json.loads(line.rstrip())
  except ValueError as ve:
    print "ERROR: {0} cannot be parsed, exception message:{1}".format(line, ve)
    continue

2）我还测试了你的json样本，它有效：

Python 2.7.10 (default, Oct 23 2015, 18:05:06)
[GCC 4.2.1 Compatible Apple LLVM 7.0.0 (clang-700.0.59.5)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> import json
>>> json.loads('{"sample": 309896986, "data": {"value": 2}, "samples": 319049477, "startTime": "20151213T00:01:47"}')
{u'sample': 309896986, u'data': {u'value': 2}, u'startTime': u'20151213T00:01:47', u'samples': 319049477}

我将示例json行保存到sample.csv并通过以下代码正确解析：导入json

with open("sample.csv") as f:
    for line in f:
        data = json.loads(line.rstrip())
        print(data)

我的猜测是它的文件中可能有一些未格式化的行。你需要调试你的行。

发出加载序列化json对象的问题

1 个答案: