This is my first question here so my sincerest apologies if I've written TOO much and thanks so much in advance for taking a look.
PROBLEM:
I've written a function which should, if necessary, call itself x times and if unsuccessful return nothing. However, when the function seems to be successful, it still returns None.
BACKGROUND: I have a number of directories which represent months in the year 2009. Not all of the months exist though, therefore if this is the case, I want to get the previous month, check if a directory for that month exists, and if not continue going back one month AT MOST for 6 months.
Below you see the month 09 in the date_tag, which in my test case does not exist. Neither does 08 or 07. Thus the function SHOULD return 06 but instead it returns None.
import pdb
import generate_months_module
import os
date_tag = '2000/2000/2009/09'
tree_location = '/Users/kelly/Documents/projects/komm/data/directory-tree/'
def iterateOverMonths(date_tag, x):
if x <= 0:
return_string = 'no dates found'
return return_string
else:
new_date = generate_months_module.handleDateShifts(date_tag)[1]
print '\tNEW DATE after calling handleDateShifts' + new_date
full_path = tree_location + '/' + new_date
if checkDirectoryExistance(full_path) == True:
print '\t'+ full_path + ' is a real path'
return full_path
else:
print 'dir does not exist'
iterateOverMonths(new_date, x-1)
def checkDirectoryExistance(dir_path):
"check if a directory exists, return true or false"
if os.path.isdir(dir_path) == True:
return True
else:
return False
print iterateOverMonths(date_tag, 6)
The generate_months_module.handleDateShifts is supposed to just get the previous month and return it. (This works in other test cases so I highly doubt the problem is here!)
My output from this then is:
6
NEW DATE after calling handleDateShifts2000/2000/2009/08
dir does not exist
5
NEW DATE after calling handleDateShifts2000/2000/2009/07
dir does not exist
4
NEW DATE after calling handleDateShifts2000/2000/2009/06
/Users/kelly/Documents/projects/komm/data/directory-tree/2000/2000/2009/06 is a real path
returning full path
None
When I use pdb.set_trace() prior to "return full_path" it seems like the function is being called again DESPITE the IF clause being True and thus writing over the "full_path" variable I want to return.
Why isn't the path "/Users/kelly/Documents/projects/komm/data/directory-tree/2000/2000/2009/06" being returned??
imported function:
If one should be interested and want to re-create this the handleDateShifts function is as follows (my apologies, it's a bit messy):
def handleDateShifts(corpus_date_string):
"get background corpus date strings ALSO call this function if month does not exist and need to go back even further"
century, decade, year, month = corpus_date_string.split('/')
if month == '01' or month == '02':
#handle date boundaries which can affect year, decade and cent
background_mo_1 = '11'
background_mo_2 = '12'
millenium_shift = re.search('[1-9][0][0][0]$', year)
century_shift = re.search('[1-9][0][0]$', year)
decade_shift = re.search('[1-9][0]$',year)
if century_shift or millenium_shift:
century = int(year) - 100
decade = int(year) - 10
year = int(year) - 1
elif decade_shift:
decade = int(year) - 10
year = int(year) - 1
elif not decade_shift and not century_shift:
year = int(year) - 1
background_1_string = str(century) +'/'+ str(decade) +'/'+ str(year) +'/'+ str(background_mo_1)
background_2_string = str(century) +'/'+ str(decade) +'/'+ str(year) +'/'+ str(background_mo_2)
else: #the cent/dec/year can stay the same
background_mo_1 = int(month) - 2
background_mo_2 = int(month) - 1
if len(str(background_mo_1)) == 1:
background_mo_1 = '0' + str(background_mo_1)
if len(str(background_mo_2)) == 1:
background_mo_2 = '0' + str(background_mo_2)
background_1_string = str(century) +'/'+ str(decade) +'/'+ str(year) +'/'+ str(background_mo_1)
background_2_string = str(century) +'/'+ str(decade) +'/'+ str(year)+'/'+ str(background_mo_2)
return background_1_string, background_2_string
