这是为托管 VM 日志查看器生成 JSON 日志的一种方法:
所需的 JSON 格式
目标是为每个日志行创建一个单行 JSON 对象,其中包含:
{
"message": "Error occurred!.",
"severity": "ERROR",
"timestamp": {
"seconds": 1437712034000,
"nanos": 905
}
}
(信息来源于谷歌:https ://code.google.com/p/googleappengine/issues/detail?id=11678#c5 )
使用 python-json-logger
见:https ://github.com/madzak/python-json-logger
def get_timestamp_dict(when=None):
"""Converts a datetime.datetime to integer milliseconds since the epoch.
Requires special handling to preserve microseconds.
Args:
when:
A datetime.datetime instance. If None, the timestamp for 'now'
will be used.
Returns:
Integer time since the epoch in milliseconds. If the supplied 'when' is
None, the return value will be None.
"""
if when is None:
when = datetime.datetime.utcnow()
ms_since_epoch = float(time.mktime(when.utctimetuple()) * 1000.0)
return {
'seconds': int(ms_since_epoch),
'nanos': int(when.microsecond / 1000.0),
}
def setup_json_logger(suffix=''):
try:
from pythonjsonlogger import jsonlogger
class GoogleJsonFormatter(jsonlogger.JsonFormatter):
FORMAT_STRING = "{message}"
def add_fields(self, log_record, record, message_dict):
super(GoogleJsonFormatter, self).add_fields(log_record,
record,
message_dict)
log_record['severity'] = record.levelname
log_record['timestamp'] = get_timestamp_dict()
log_record['message'] = self.FORMAT_STRING.format(
message=record.message,
filename=record.filename,
)
formatter = GoogleJsonFormatter()
log_path = '/var/log/app_engine/custom_logs/worker'+suffix+'.log.json'
make_sure_path_exists(log_path)
file_handler = logging.FileHandler(log_path)
file_handler.setFormatter(formatter)
logging.getLogger().addHandler(file_handler)
except OSError:
logging.warn("Custom log path not found for production logging")
except ImportError:
logging.warn("JSON Formatting not available")
要使用,只需调用setup_json_logger
- 您可能还想更改worker
日志的名称。