Added reltime

server/reltime.py

@@ -0,0 +1,161 @@
+'''
+ A relative time parser
+
+ parsers english time strings and returns the number of seconds that the 
+ input represents. Throws a
+ ValueError if the input can't be parsed as a time string.
+
+ Some examples:
+
+ parse_to_rel_time("1 month") -> 2592000
+ parse_to_rel_time("2 days 2 hours") -> 180000
+ parse_to_rel_time("3 years 2 months 2 days") -> 99964800
+ parse_to_rel_time("3 years 2 months and 2 days ago") -> 99964800
+ parse_to_rel_time("3 years, 2 months and 22 days ago!") -> 101692800
+ parse_to_rel_time(" 3 years, 2 months and 22 days ago! ") -> 101692800
+ parse_to_rel_time("1 h 3 w 2 d") -> 1990800
+ parse_to_rel_time("last week") -> 604800
+ parse_to_rel_time("six weeks") -> 3628800
+ parse_to_rel_time("a week ago") -> 604800
+ parse_to_rel_time("twenty days ago") -> 1728000
+
+'''
+
+import re
+
+# 1m
+# 5Y3M2W4D3h2m2s
+# 5 years 3 months 2 weeks 4 days 3 hours 2 mins 2 secs
+# 5 Y 3 M 2 W 4 D 3h 2 m 2 s
+
+def parse_to_rel_time(str):
+ stop_words = set(['and', 'ago', 'since'])
+ delta_types = {
+ 'second':1,
+ 'sec':1,
+ 'secs':1,
+ 'seconds':1,
+ 'second':1,
+ 'minute':60,
+
+ 'm':60,
+ 'min':60,
+ 'minute':60,
+ 'minutes':60,
+
+ 'h':3600,
+ 'hr':3600,
+ 'hrs':3600,
+ 'hour':3600,
+ 'hours':3600,
+
+ 'day':60 * 60 * 24,
+ 'd':60 * 60 * 24,
+ 'days':60 * 60 * 24,
+
+ 'fortnight':60 * 60 * 2 * 7,
+
+ 'week':60 * 60 * 24 * 7,
+ 'weeks':60 * 60 * 24 * 7,
+ 'wks':60 * 60 * 24 * 7,
+ 'w':60 * 60 * 24 * 7,
+
+ 'month':60 * 60 * 24 * 30,
+ 'months':60 * 60 * 24 * 30,
+ 'mth':60 * 60 * 24 * 30,
+ 'mths':60 * 60 * 24 * 30,
+ 'mnth':60 * 60 * 24 * 30,
+ 'mnths':60 * 60 * 24 * 30,
+
+ 'year':60 * 60 * 24 * 365,
+ 'years':60 * 60 * 24 * 365,
+ 'yr':60 * 60 * 24 * 365,
+ 'yrs':60 * 60 * 24 * 365,
+ 'y':60 * 60 * 24 * 365,
+ }
+
+ num_subs = {
+ 'last': 1, 'a': 1, 'one': 1, 'two': 2, 'three': 3,
+ 'four': 4, 'five': 5, 'six': 6, 'seven': 7, 'eight': 8,
+ 'nine': 9, 'ten': 10, 'eleven': 11, 'twelve': 12, 'thirteen': 13,
+ 'fourteen': 14, 'fifteen': 15, 'sixteen': 16, 'seventeen': 17,
+ 'eighteen': 18, 'nineteen': 19, 'twenty': 20,
+ }
+
+ delta = 0
+ words = re.findall(r"[\w]+", str)
+ words = [w for w in words if w not in stop_words]
+ if len(words) % 2 == 1:
+ raise ValueError('bad time format: ' + str)
+
+ for i in xrange(0, len(words), 2):
+ snum = words[i]
+ type = words[i + 1].lower()
+
+ if snum in num_subs:
+ num = num_subs[snum]
+ else:
+ try:
+ num = int(snum)
+ except:
+ raise ValueError('number expected, but found ' + snum + ' instead in ' + str)
+
+ if type in delta_types:
+ delta += delta_types[type] * num
+ else:
+ raise ValueError('type expected, but found ' + type + ' instead in ' + str)
+
+ return delta
+
+if __name__ == '__main__':
+ HOUR = 60 * 60
+ DAY = 60 * 60 * 24
+ WEEK = 60 * 60 * 24 * 7
+ MONTH = 60 * 60 * 24 * 30
+ YEAR = 60 * 60 * 24 * 365
+
+ tests = [
+ ("1 month", 1 * MONTH),
+ ("2 days 2 hours", 2 * DAY + 2 * HOUR),
+ ("3 years 2 months 2 days", 3 * YEAR + 2 * MONTH + 2 * DAY),
+ ("3 years 2 months and 2 days ago", 3 * YEAR + 2 * MONTH + 2 * DAY),
+ ("3 years, 2 months and 22 days ago!", 3 * YEAR + 2 * MONTH + 22 * DAY),
+ (" 3 years, 2 months and 22 days ago! ", 3 * YEAR + 2 * MONTH + 22 * DAY),
+ ("1 h 3 w 2 d", 1 * HOUR + 3 * WEEK + 2 * DAY),
+ ("last week", 1 * WEEK),
+ ("last year and 3 weeks ago", 1 * YEAR + 3 * WEEK),
+ ("six weeks", 6 * WEEK),
+ ("a week ago", 1 * WEEK),
+ ("twenty days ago", 20 * DAY),
+ ("6 mnths, 2 wks", 6 * MONTH + 2 * WEEK),
+ ]
+
+ bad_patterns = [
+ "1",
+ ]
+
+ for stest, res in tests:
+ time = parse_to_rel_time(stest)
+ if time == res:
+ print "GOOD", stest, time
+ else:
+ print "BAD", stest, res, time
+
+ print
+ print 'testing bad patterns'
+ for bp in bad_patterns:
+ try:
+ time = parse_to_rel_time(bp)
+ print 'BAD', 'unexpected parse of', bp
+ except ValueError as e:
+ print 'GOOD', e
+
+ print "some time examples"
+ for stest, res in tests:
+ print 'parse_to_rel_time("' + stest + '")', '->', res
+
+ print "some time examples"
+ for stest, res in tests:
+ print "<li>" + stest + "</li>"
+ print
+