#!/usr/bin/env python
"""
2012-03-05, weeee!
This is a really simple script, the docs are WAY longer, that
dices a date-string returning a list of integers or a dict if
key-words are supplied.
... IT SLICES, IT DICES, IT HAS SHARP EDGES!
===============================================
Not production-ready, 'nless you like to play with razors.
There is no type-checking, no assertion for field-order etc.
This simply, blindly and unintelligently guts the string.
If the order changes, it bites... you get the idea.
Some examples, more plus arg-defs b'low
TEST_DATE = "2012-03-05 13:05:14.453728"
# return list of int's in original order
cheap_date(TEST_DATE)
[2012, 3, 5, 13, 5, 14, 453728]
ISO_KEYS = ['t_year','t_mon','...'t_sec','t_usec']
# return same list, mapped into a dict
cheap_date(TEST_DATE, ISO_KEYS)
{'t_mon': 3, 't_min': 5, 't_sec': 14, 't_hour': 13,
't_day': 5, 't_year': 2012, 't_usec': 453728}
# Keep the decimal t'gether using non-default regex
# Note: list is str's, int("12.34") razors a ValueError
cheap_date(TEST_DATE, [], DIG_N_DEC, str)
['2012', '03', '05', '13', '05', '14.453728']
# dict's and format strings, naturally sweeeeet
FMT_STR % cheap_date(TEST_DATE, ISO_KEYS, DIG_N_DEC, PAT)
2012-03-05T13:05:14.454
FMT_STR2 % cheap_date(TEST_DATE, ISO_KEYS, val_conv = str)
13:05-03/05/2012
"""
import re
def cheap_date(dt_str, kw_list = [], reg_xp = r'\D', val_conv = int):
""" Cheap incremental date parser preserving ISO microseconds
dt_str: String representing source date
pass "2012-03-05 13:05:14.453728"
returns [2012, 3, 5, 13, 5, 14, 453728]
optional- ['2012', '03', '05', '13', '05', '14.453728']
returns {'tm_year': 2012, 'tm_mday': 5, 'tm_mon': 3 ... }
Optional arguments:
kw_list: Ordered list of return-dictionary keys
reg_xp: Regular expression used to split the string
val_conv: List-processor for data-conversion i.e. str --> int
>>> cheap_date(TEST_DATE)
[2012, 3, 5, 13, 5, 14, 453728]
>>> cheap_date(TEST_DATE, ISO_KEYS[:3])
{'t_mon': 3, 't_day': 5, 't_year': 2012}
>>> FMT_STR2 % cheap_date(TEST_DATE, ISO_KEYS, val_conv = str)
'13:05-03/05/2012'
"""
# shake the numbers out with re ['2012', '03'...]
tm_list = re.split(reg_xp, dt_str)
# juice 'em: apply function to each list-value [2012, 03...]
# you _could_ test if val_conv == str an omit this step
tm_list = map(val_conv, tm_list)
# Existence of this list, enables return of a dictionary
if kw_list:
# fabricate list of key-value pairs [['yr',2012],[....],]
tm_list = zip(kw_list, tm_list)
# map the key-val pairs into a dict to be proud of
tm_list = dict(tm_list)
return tm_list
def cheaper_date(dt_str, kw_list = [], reg_xp = r'\D', val_conv = int):
""" Cheaper date parser, with a few less teeth
>>> FMT_STR2 % cheaper_date(TEST_DATE, ISO_KEYS, val_conv = str)
'13:05-03/05/2012'
"""
# The functionality above, tucked in a thin blankie.
try:
tm_list = map(val_conv, re.split(reg_xp, dt_str))
except ValueError, e:
print "Conversion proc (int?) spewed a matched value"
print e
raise
if kw_list:
tm_list = dict(zip(kw_list, tm_list))
return tm_list
if __name__ == '__main__':
import doctest
# Some Q&D convenience, ta get 'r done.
TEST_DATE = "2012-03-05 13:05:14.453728"
# Keys match number-seq. order of date to parse
ISO_KEYS = ['t_year','t_mon','t_day','t_hour','t_min','t_sec','t_usec']
# Slow lrner moi! Ages till I grep'd the non-obv. & betwix da lines.
# A.K.A: "To select or not select? TITQ!" I mean "\d" to "\D"
# The following exp. splits, and discards, NON-number sequences.
DIGITS_ONLY = r'\D' # DEFAULT, digits only: 12.56-> ['12','56']
# \d is inverse|not \D, [^....] inverse|not's the match
DIG_N_DEC = r'[^\d\.]' # retain decmal no's 34.78-> ['34.78',]
# With a dict[ionary] and format strings, it happens eh?
FMT_STR = "T".join(["%(t_year)d-%(t_mon)02d-%(t_day)02d",
"%(t_hour)02d:%(t_min)02d:%(t_sec)0.3f"])
# Same info, just shuffled for my simple-minded amusement
FMT_STR2 = "%(t_hour)s:%(t_min)s-%(t_mon)s/%(t_day)s/%(t_year)s"
# Pick-A-Type... for demo. Its stupid, assumes a string of digits only.
# There are safer/elegantisher ways to do this... more calories though.
def PAT(s):
try:
return int(s)
except ValueError:
return float(s)
doctest.testmod()
