UPDATE: i added two small fixes. When a functions is returning let’s pass the return value further, and exception when there’s no parameters.
I began studying more about decorators. I made a simple one for now it can be used to calculate execution time in miliseconds,seconds,minutes or hours of function decorated. It uses closures with wrapper function for handling parameters. Next time i’ll post decorator for running a function in a background using threads.
Here’s the code:
''' @author: marcink '''
import time
from types import FunctionType
class GetExecutionTime:
'''
This generic class is meant to be used as decorator for messuring
simple method execution time it works on class methods as well
as regular non class functions ;
Availible parameters:
'ms' - miliseconds
's' - seconds
'm' - minutes
'h' - hours
usage: @GetExecutionTime(param)
samples:
@GetExecutionTime('s')
def samplemethod(self,params):
function body
will print executions time at end in seconds
@GetExecutionTime('m')
def samplemethod(params):
function body
will print executions time at end in minutes
'''
def __init__(self, *args):
#in case of calling without parametrs
#first argument will be the function decorated raise exception than
if len(args) is 0 or type(args[0]) is FunctionType:
raise Exception("Calling decorator without parameters is not possible")
else:
self.fn = None
self.d_as = args[0]
def miliseconds():return 1
def seconds(): return 10000000000
def minutes():return seconds() * 60
def hours(): return minutes() * 60
def default_():return seconds()
#this is a cool way to replace switch case with default parameter
commands = {'ms':miliseconds,
's':seconds,
'm':minutes,
'h':hours}
self.display_as = commands.get(self.d_as, default_)()
def __call__(self,fn):
display_as = self.display_as
d_as = self.d_as
def wrapper_function(*args, **kwargs):
start = time.time()
ret = fn(*args,**kwargs)
end = time.time()
microsec = (end - start) * 10000000000
print "function %s execution time: %s %s" % (fn.__name__, (microsec) / display_as, d_as)
if ret:
return ret
return wrapper_function
#EXAMPLES:
from time import sleep
@GetExecutionTime('s')
def short_func(max, min):
for x in range(3):
sleep(1)
print max,min
return (max, min)
short_func(100, 10)
''' prints: function short_func execution time: 3.00342392921 s '''
