This is the module. I return the prefix REPEC, if a shift has
happened.
make() makes the obfuscated handle. ekam() is the opposite,
for testing. JMBC can perlify.
I tested this on about 97000 handles from ArchEc.
--
Written by Thomas Krichel http://openlib.org/home/krichel on his 21077th day.
## obfuscate.py
import datetime
class Obfuscate:
def __init__(self, do_verbose=False):
return None
def from_file(self, fufi, cut):
"""testing routine, can be deleted"""
## read handles from a file
handles_file = open(fufi, 'r')
while True:
line = handles_file.readline()
if not line:
break
self.work_on_line(line.strip(), cut)
return None
def work_on_line(self, line, cut):
# # in case we have a prefix of the handle
old = line[cut:]
new = self.make(old)
check = self.ekam(new)
check_lc = check.lower()
old_lc = old.lower()
if not check_lc == old_lc:
raise Exception(f"inconsistency on {old} --> {new}")
def make(self, old):
"""main function used by external callers"""
if not (old.startswith('repec') or old.startswith('RePEc')):
print(old)
quit()
old_date = old[10:20]
if old == 'RePEc:per':
return old
try:
old_parsed = datetime.datetime.strptime(old_date, '%Y-%m-%d')
except ValueError:
return old
year = int(old_parsed.strftime("%Y"))
if year < 1900:
# # early dates could be confusing because of changes
# # in adoption of Greogian calendar
return old
if year > 2100:
# # I see no reason to obfuscate these
return old
shift = len(old)
if shift % 2 == 1:
# # for odd values, take negative
shift = -shift
new_parsed = old_parsed + datetime.timedelta(days=shift)
new_date = new_parsed.strftime("%Y-%m-%d")
new = old.replace(old_date, new_date, 1)
new = new.replace('repec', 'REPEC')
new = new.replace('RePEc', 'REPEC')
return new
def ekam(self, new):
"""opposite of make, a check"""
if new == 'RePEc:per':
return new
if not new.startswith('REPEC'):
return new
new_date = new[10:20]
new_parsed = datetime.datetime.strptime(new_date, '%Y-%m-%d')
shift = len(new)
if shift % 2 == 0:
# # for even values, take negative
shift = -shift
old_parsed = new_parsed + datetime.timedelta(days=shift)
old_date = old_parsed.strftime("%Y-%m-%d")
old = new.replace('REPEC', 'RePEc')
old = old.replace(new_date, old_date)
return old
