Is there a better way to only print when run as a script, when __name__ == '__main__' ?
I have some scripts that I also import and use parts of.
Something like the below will work but is ugly, and would have to be defined in each script separately:
def printif(s):
if globals()['__name__'] == '__main__':
print (s)
return
I looked briefly at some of python's logging libraries but would prefer a two lighter solution...
edit:
I ended up doing something like this:
# mylog.py
import sys
import logging
log = logging.getLogger()
#default logging level
log.setLevel(logging.WARNING)
log.addHandler(logging.StreamHandler(sys.stdout))
And from the script:
import log from mylog
...
log.info(...)
log.warning(...)
...
if __name__ == '__main__':
#override when script is run..
log.setLevel(logger.INFO)
This scheme has minimal code duplication, per script log levels, and a project-wide default level...which is exactly what I wanted.
run_as_script = False
def printif(s):
if run_as_script:
print (s)
return
if __name__ == '__main__':
run_as_script = True
In light of user318904's comment on my other answer, I'll provide an alternative (although this may not work in all cases, it might just be "good enough").
For a separate module:
import sys
def printif(s):
if sys.argv[0] != '':
print (s)
Using a logging library is really not that heavyweight:
import logging
log = logging.getLogger('myscript')
def dostuff(...):
....
log.info('message!')
...
if __name__ == '__main__':
import sys
log.setLevel(logging.INFO)
log.addHandler(logging.StreamHandler(sys.stdout))
...
One wart is the "WARNING: no handlers found for myscript" message that logging prints by default if you import this module (rather than run it as a script), and call your function without setting up logging. It'll be gone in Python 3.2. For Python 2.7, you can shut it off by adding
log.addHandler(logging.NullHandler())
at the top, and for older versions you'd have to define a NullHandler class like this:
class NullHandler(logging.Handler):
def emit(self, record):
pass
Looking back at all this, I say: go with Gerrat's suggestion. I'll leave mine here, for completeness.
Related
I'd like to know if there's a way to log the same thing in two files in twisted.
Let's say this is the code, now I'd like the same output going to "logs.log" to be redirected to sys.stdout.
if __name__ == "__main__":
log.startLogging(open("logs.log", 'a'))
log.startLogging(sys.stdout)
This is absolutely possible and easier than ever before if you're on the latest version of Twisted.
from sys import stdout
from twisted.logger import Logger, textFileLogObserver, globalLogBeginner
# start the global logger
logfile = open('log.log', 'a')
globalLogBeginner.beginLoggingTo([
textFileLogObserver(stdout),
textFileLogObserver(logfile)])
log = Logger()
log.info('hello world')
log.debug('hello world')
You can also implement you own logger if you want custom messages.
I wanted to mix a config.py approach and ConfigParser to set some default values in config.py which could be overridden by the user in its root folder:
import ConfigParser
import os
CACHE_FOLDER = 'cache'
CSV_FOLDER = 'csv'
def main():
cp = ConfigParser.ConfigParser()
cp.readfp(open('defaults.cfg'))
cp.read(os.path.expanduser('~/.python-tools.cfg'))
CACHE_FOLDER = cp.get('folders', 'cache_folder')
CSV_FOLDER = cp.get('folders', 'csv_folder')
if __name__ == '__main__':
main()
When running this module I can see the value of CACHE_FOLDER being changed. However when in another module I do the following:
import config
def main()
print config.CACHE_FOLDER
This will print the original value of the variable ('cache').
Am I doing something wrong ?
The main function in the code you show only gets run when that module is run as a script (due to the if __name__ == '__main__' block). If you want that turn run any time the module is loaded, you should get rid of that restriction. If there's extra code that actually does something useful in the main function, in addition to setting up the configuration, you might want to split that part out from the setup code:
def setup():
# the configuration stuff from main in the question
def main():
# other stuff to be done when run as a script
setup() # called unconditionally, so it will run if you import this module
if __name__ == "__main__":
main() # this is called only when the module is run as a script
I am trying to write some python code using tornado. Here is my code.
import sys
import tornado.ioloop
import tornado.web
import constants
class student():
name = ""
class MainHandler(tornado.web.RequestHandler):
def get(self):
loader = tornado.template.Loader(".")
print "MainiiiHandler"
self.write(loader.load("base.html").generate(pics=constants.pics))
application = tornado.web.Application([
(r"/", MainHandler),
])
if __name__ == "__main__":
application.listen(8888)
tornado.ioloop.IOLoop.instance().start()
So when i visit 127.0.0.1:8888, it should print MainiiiHandler in terminal. When i run python code with 'python test.py', it turns out actually like this. But when i run with :make in vim, it won't print MainiiiHandler. Because i really like the make function in vim, so can you help me solve this problem.
Check how
makeprg is python %
is written.
:set makeprg="python %"
does NOT work for me (echoes an empty string)
while
:set makeprg=python\ %
actually DOES work.
(if it doesn't help) This is what :h make shows:
The program given with the 'makeprg' option is started (default "make") with the optional [arguments] and the output is saved in the errorfile (for Unix it is also echoed on the screen).
If your system is not Unix, I suppose you have to supply the code that will print the contents of errorfile for you (don't know for sure as I tested it only under Linux).
I am a newbie in process of learning python and currently working on a automation project.
And i have N numbers of testcase which needs to be run on reading material people suggest me to use nosetest.
What is the way to run multiple testcase using nosetest?
And is the correct approach doing it:
import threading
import time
import logging
import GLOBAL
import os
from EPP import EPP
import Queue
import unittest
global EPP_Queue
from test1 import test1
from test2 import test2
logging.basicConfig(level=logging.DEBUG,
format='(%(threadName)-10s) %(message)s',
)
class all_test(threading.Thread,unittest.TestCase):
def cleanup():
if os.path.exists("/dev/epp_dev"):
os.unlink("/dev/epp_dev")
print "starts here"
server_ip ='192.168.10.15'
EppQueue = Queue.Queue(1)
EPP = threading.Thread(name='EPP', target=EPP,
args=('192.168.10.125',54321,'/dev/ttyS17',
EppQueue,))
EPP.setDaemon(True)
EPP.start()
time.sleep(5)
suite1 = unittest.TestLoader().loadTestsFromTestCase(test1)
suite2 = unittest.TestLoader().loadTestsFromTestCase(test2)
return unittest.TestSuite([suite1, suite2])
print "final"
raw_input("keyy")
def main():
unittest.main()
if __name__ == '__main__':
main()
Read
http://ivory.idyll.org/articles/nose-intro.html.
Download the package
http://darcs.idyll.org/~t/projects/nose-demo.tar.gz
Follow the instructions provided in the first link.
nosetest, when run from command line like 'nosetest' or 'nosetest-2.6' will recursively hunt for tests in the directory you execute it in.
So if you have a directory holding N tests, just execute it in that directory. They will all be executed.
[Closing NOTE]
Thank you everyone that trying to help me.
I've found the problem and it have nothing to do with python understanding of mine (which is little). :p
The problem is that I edit the wrong branch of the same project, Main.py in one branch and XWinInfos.py in another branch.
Thanks anyway.
[Original Question]
I am a Java/PHP/Delphi programmer and only use Python when hack someone else program -- never to write a complex Python myself. Since I have a short free time this week, I determine to write something non-trivia with Python and here is my problem
First I have python files like this:
src/
main.py
SomeUtils.py
In "SomeUtils.py, I have a few functions and one class:
...
def funct1 ...
def funct2 ...
class MyClass1:
__init__(self):
self. ....
...
Then in "main.py", I use the function and class:
from SomeUtils import *;
def main():
funct1(); # Use funct1 without problem;
aMyObj1 = MyClass1(); # Use MyClass1 with error
if (__name__ == "__main__"):
main();
The problem is that the functions are used without any problem what so ever but I cannot use the class.
The error is:
NameError: global name 'MyClass1' is not defined
What is the problem here? and What can I do?
EDIT: Thanks for answers for I still have problem. :(
When I change the import statements to:
from SomeUtils import funct1
from SomeUtils import MyClass1
I have this error
ImportError: cannot import name MyClass1
EDIT 2:----------------------------------------------------------
Thanks you guys.
I think, it may be better to post the actual code, so here it is:
NOTE: I am aware about ";" and "(...)" but I like it this way.
Here is the dir structure.
DIRS http://dl.getdropbox.com/u/1961549/images/Python_import_prolem_dir_.png
as you see, I just add an empty init.py but it seems to make no different.
Here is main.py:
from XWinInfos import GetCurrentWindowTitle;
from XWinInfos import XWinInfo;
def main():
print GetCurrentWindowTitle();
aXWinInfo = XWinInfo();
if (__name__ == "__main__"):
main();
Here is XWinInfos.py:
from subprocess import Popen;
from subprocess import PIPE;
from RegExUtils import GetTail_ofLine_withPrefix;
def GetCurrentWindowID():
aXProp = Popen(["xprop", "-root"], stdout=PIPE).communicate()[0];
aLine = GetTail_ofLine_withPrefix("_NET_ACTIVE_WINDOW\(WINDOW\): window id # 0x", aXProp);
return aLine;
def GetCurrentWindowTitle():
aWinID = GetCurrentWindowID();
aWinTitle = GetWindowTitle(aWinID);
return aWinTitle;
def GetWindowTitle(pWinID):
if (aWinID == None): return None
aWMCtrlList = Popen(["wmctrl", "-l"], stdout=PIPE).communicate()[0];
aWinTitle = GetTail_ofLine_withPrefix("0x[0-9a-fA-F]*" + aWinID + "[ ]+[\-]?[0-9]+[ ]+[^\ ]+[ ]+", aWMCtrlList);
return aWinTitle;
class XWinInfo:
def __init__(self):
aWinID = GetCurrentWindowID();
self.WinID = pWinID;
self.Title = GetWindowTitle(pWinID);
The file RegExUtils.py holds a function "GetTail_ofLine_withPrefix" which work fine so.
If I use "from XWinInfos import *;", the error goes "NameError: global name 'XWinInfo' is not defined".
If I use "from XWinInfos import XWinInfo;", the error goes "ImportError: cannot import name XWinInfo".
Please helps.
Thanks in advance.
Hmm... there's several typos in your example, so I wonder if your actual code has some typos as well. Here's the complete source from a quick test that does work fine without import errors.
SomeUtils.py:
def funct1():
print('Function 1')
def funct2():
print('Function 2')
class MyClass1(object):
def __init__(self):
print('MyClass')
main.py:
from SomeUtils import *
def main():
funct1()
aObj = MyClass1()
if (__name__ == "__main__"):
main()
[EDIT Based on OP additional info]
I still can't recreate the same error, but the code you posted won't initially work for at least a couple of errors in the XWinInfox.py init method:
self.WinID = pWinID #change to 'aWinID' since pWinID is not defined
self.Title = GetWindowTitle(pWinID) #change to 'aWinID'since pWinID is not defined
so a corrected version would read:
self.WinID = aWinID
self.Title = GetWindowTitle(aWinID)
Also, you have a typo in your init file name, there should be two underscores before AND after the 'init' word. Right now you have '__init_.py' and it should be '__init__.py', however this shouldn't keep your code from working.
Because I don't have the RegExUtils.py code, I just stubbed out the methods that rely on that file. With the stubbed methods and correcting the aforementioned typos, the code you post now works.
why are you importing from XWinInfos? you should be importing from SomeUtils. Not to mention that *-style imports are discouraged.
Edit: your error
ImportError: cannot import name MyClass1
basically tells you that there is no MyClass1 defined in the SomeUtils. It could be because you have another SomeUtils.py file somewhere on the system path and it being imported instead. If that file doesn't have MyClass1, you'd get this error.
Again: it's irrelevant whether you class MyClass1 exist. What might be the case is that you have another XWinInfos.p(y|o|w) somewhere on your system and it's being imported. Otherwise: norepro.
You may want to rewrite main.py as follows:
import SomeUtils as util
def main():
util.funct1() # Use funct1 without problem;
aMyObj1 = util.MyClass1() # Use MyClass1 with error
if __name__ == "__main__":
main()
A few quick notes:
There is no need for semicolons in
Python unless you have more than one
statement on a line
There is no need
to wrap conditional tests in
parentheses except for grouping
from
module import * is discouraged as it
pollutes the global namespace
I suppose you mean
from SomeUtils import *
however, that does not trigger the error for me. This works fine for me:
SomeUtils.py
def funct1():
print 4
class MyClass1:
def __init__(self):
print 8
main.py
from SomeUtils import *
def main():
funct1() # Use funct1 without problem;
aMyObj1 = MyClass1() # Use MyClass1 without error
if (__name__ == "__main__"):
main()
Your question is naturally linked to a lot of SO older one.
See, just for reference, SO1342128 and SO1057843