Using logging module to log either to screen or a file

[Jean-Michel Pichavant]

RedBaron wrote:
> Hi,
> I am beginner to python and i am writing a program that does a lot of
> things. One of the requirements is that the program shud generate a
> log file. I came across python loggging module and found it very
> useful. But I have a few problems
> Suppose by giving option '-v' along with the program the user can turn
> off logging to a file and instead display log on the screen. Since I
> am using a config file for logging, how do I accomplish this.
> I tried to define two handlers (fil and screen) and added it to my
> logger. But that logs data to both screen and the file. I need to log
> it to only one. How do I dynamically remove one of the handler from
> the logger based on user option. As a precursor how do i reference the
> handlers defined in config file in the code??
>   
your logger has a public 'handlers' attribute.

consoleHandlers = [h for h in logger.handlers if h.__class__ is 
logging.StreamHandler] # the list of handlers logging to the console 
(assuming they are instances of the StreamHandler class)

if consoleHandlers:
    h1 = consoleHandlers[0]
    h1.filter = lambda x:True # enable the handler
    h1.filter = lambda x:False # disable the handler


JM