我正在尝试格式化logging的输出，以使levelname始终位于终端的右侧。 我目前有一个脚本，如下所示：
import logging, os, time
fn = 'FN'
start = time.time()
def getTerminalSize():
import os
env = os.environ
def ioctl_GWINSZ(fd):
try:
import fcntl, termios, struct, os
cr = struct.unpack('hh', fcntl.ioctl(fd, termios.TIOCGWINSZ,
'1234'))
except:
return
return cr
cr = ioctl_GWINSZ(0) or ioctl_GWINSZ(1) or ioctl_GWINSZ(2)
if not cr:
try:
fd = os.open(os.ctermid(), os.O_RDONLY)
cr = ioctl_GWINSZ(fd)
os.close(fd)
except:
pass
if not cr:
cr = (env.get('LINES', 25), env.get('COLUMNS', 80))
return int(cr[1]), int(cr[0])
(width, _) = getTerminalSize()
level_width = 8
message_width = width - level_width - 4
FORMAT = '%(message)-{len1:{width1}d}s [%(levelname){len2:{width2}d}s]'.format(
len1 = message_width,_
len2 = level_width,_
width1 = len(str(message_width)),_
width2 = len(str(level_width)))
logging.basicConfig(format=FORMAT, level="DEBUG")
logging.debug("Debug Message")
logging.info("Info Message")
logging.warning("Warning Message")
logging.error("Error Message")
logging.critical("Critical Message")
logging.info("Starting File: " + os.path.basename(fn) + "n-----------------------------------------")
logging.info("tTo read data: %s"%(time.time() - start))
输出如下所示：
Debug Message [ DEBUG]
Info Message [ INFO]
Warning Message [ WARNING]
Error Message [ ERROR]
Critical Message [CRITICAL]
Starting File: Channel209.Raw32
----------------------------------------- [ INFO]
To read data: 0.281999826431 [
INFO]
我希望输出看起来像这样，但无法完全弄清楚：
Debug Message [ DEBUG]
Info Message [ INFO]
Warning Message [ WARNING]
Error Message [ ERROR]
Critical Message [CRITICAL]
Starting File: Channel209.Raw32
----------------------------------------- [ INFO]
To read data: 0.281999826431 [ INFO]
正如@Carpetsmoker所说，要做我真正想要的事情，需要创建一个覆盖默认值的新格式化程序类。
以下类适用于此过程：
import logging
import textwrap
import itertools
'''
MyFormatter class
Adapted from: https://stackoverflow.com/questions/6847862/how-to-change-the-format-of-logged-messages-temporarily-in-python
https://stackoverflow.com/questions/3096402/python-string-formatter-for-paragraphs
Authors: Vinay Sajip, unutbu
'''
class MyFormatter(logging.Formatter):
#This function overwrites logging.Formatter.format
#We conver the msg into the overall format we want to see
def format(self,record):
widths=[getTerminalSize()[0] - 12 ,10]
form='{row[0]:<{width[0]}} {row[1]:<{width[1]}}'
#Instead of formatting...rewrite message as desired here
record.msg = self.Create_Columns(form,widths,[record.msg],["[%8s]"%record.levelname])
#Return basic formatter
return super(MyFormatter,self).format(record)
def Create_Columns(self,format_str,widths,*columns):
'''
format_str describes the format of the report.
{row[i]} is replaced by data from the ith element of columns.
widths is expected to be a list of integers.
{width[i]} is replaced by the ith element of the list widths.
All the power of Python's string format spec is available for you to use
in format_str. You can use it to define fill characters, alignment, width, type, etc.
formatter takes an arbitrary number of arguments.
Every argument after format_str and widths should be a list of strings.
Each list contains the data for one column of the report.
formatter returns the report as one big string.
'''
result=[]
for row in zip(*columns):
#Create a indents for each row...
sub = []
#Loop through
for r in row:
#Expand tabs to spaces to make our lives easier
r = r.expandtabs()
#Find the leading spaces and create indend character
if r.find(" ") == 0:
i = 0
for letters in r:
if not letters == " ":
break
i += 1
sub.append(" "*i)
else:
sub.append("")
#Actually wrap and creat the string to return...stolen from internet
lines=[textwrap.wrap(elt, width=num, subsequent_indent=ind) for elt,num,ind in zip(row,widths,sub)]
for line in itertools.izip_longest(*lines,fillvalue=''):
result.append(format_str.format(width=widths,row=line))
return 'n'.join(result)
它依赖于在某个称为 getTerminalSize 的函数中获取终端大小。 我使用了Harco Kuppens的方法，我不会在这里转发。
驱动程序示例如下，其中MyFormatter和getTerminalSize位于Colorer：
import logging
import Colorer
logger = logging.getLogger()
logger_handler = logging.StreamHandler()
logger.addHandler(logger_handler)
logger_handler.setFormatter(Colorer.MyFormatter("%(message)s"))
logger.setLevel("DEBUG")
logging.debug("ttTHIS IS A REALY long DEBUG Message that works and wraps around great........")
logging.info(" THIS IS A REALY long INFO Message that works and wraps around great........")
logging.warning("THIS IS A REALY long WARNING Message that works and wraps around great........")
logging.error("tTHIS IS A REALY long ERROR Message that works and wraps around great........")
logging.critical("THIS IS A REALY long CRITICAL Message that works and wraps around great........")
输出在哪里（为提高可读性而注释）：
# THIS IS A REALY long DEBUG Message that works and [ DEBUG]
# wraps around great........
# THIS IS A REALY long INFO Message that works and wraps around [ INFO]
# great........
# THIS IS A REALY long WARNING Message that works and wraps around [ WARNING]
# great........
# THIS IS A REALY long ERROR Message that works and wraps [ ERROR]
# around great........
# THIS IS A REALY long CRITICAL Message that works and wraps around [CRITICAL]
# great........
我修改了最后几行，如下所示：
logging.info("Starting File: %s" % os.path.basename(fn))
logging.info("%s" % ('-' * 15))
logging.info(" To read data: %s" % (time.time() - start))
您的错误是使用了换行符 （ n） 和制表符 （ t ） 字符。
或者，如果您必须保留换行符（这对我来说似乎很奇怪），您可以手动添加空格，如下所示：
logging.info("Starting File: %sn%s%s" % (
os.path.basename(fn),
('-' * 15),
' ' * (width - 15 - 12)))
其他注意事项
您应该创建一个最小、完整、经过测试和可读的。您的代码不起作用，我需要修改一些内容才能运行示例。查看您的消息编辑历史记录，了解我必须编辑的内容。
从 Python 3.3 开始，就有os.get_terminal_size.如果这不可用，那么做subprocess.call(['tput cols'], shell=True)对我来说似乎简单得多......