X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=sfa%2Futil%2Fsfatime.py;h=75a2e4a3e6c9a75ce27f91d8165b88be436d70c7;hb=d59f8e0b663b71d8c349017d0ecb37cb6bc527a1;hp=901b4e0d79f94e588dc69c604ac2dc2aad421a32;hpb=0d9988520909b74d702b05a9ce63a36e7e41e2f1;p=sfa.git

diff --git a/sfa/util/sfatime.py b/sfa/util/sfatime.py
index 901b4e0d..75a2e4a3 100644
--- a/sfa/util/sfatime.py
+++ b/sfa/util/sfatime.py
@@ -1,10 +1,115 @@
+#----------------------------------------------------------------------
+# Copyright (c) 2008 Board of Trustees, Princeton University
+#
+# Permission is hereby granted, free of charge, to any person obtaining
+# a copy of this software and/or hardware specification (the "Work") to
+# deal in the Work without restriction, including without limitation the
+# rights to use, copy, modify, merge, publish, distribute, sublicense,
+# and/or sell copies of the Work, and to permit persons to whom the Work
+# is furnished to do so, subject to the following conditions:
+#
+# The above copyright notice and this permission notice shall be
+# included in all copies or substantial portions of the Work.
+#
+# THE WORK IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+# OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+# HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
+# WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+# OUT OF OR IN CONNECTION WITH THE WORK OR THE USE OR OTHER DEALINGS
+# IN THE WORK.
+#----------------------------------------------------------------------
+from types import StringTypes
+import time
+import datetime
 import dateutil.parser
+import calendar
+import re
 
-def utcparse(str):
+from sfa.util.sfalogging import logger
+
+SFATIME_FORMAT = "%Y-%m-%dT%H:%M:%SZ"
+
+def utcparse(input):
     """ Translate a string into a time using dateutil.parser.parse but make sure it's in UTC time and strip
-    the timezone, so that it's compatible with normal datetime.datetime objects"""
-    
-    t = dateutil.parser.parse(str)
-    if not t.utcoffset() is None:
-        t = t.utcoffset() + t.replace(tzinfo=None)
-    return t
+the timezone, so that it's compatible with normal datetime.datetime objects.
+
+For safety this can also handle inputs that are either timestamps, or datetimes
+"""
+
+    def handle_shorthands (input):
+        """recognize string like +5d or +3w or +2m as 
+        2 days, 3 weeks or 2 months from now"""
+        if input.startswith('+'):
+            match=re.match (r"([0-9]+)([dwm])",input[1:])
+            if match:
+                how_many=int(match.group(1))
+                what=match.group(2)
+                if what == 'd':         d=datetime.timedelta(days=how_many)
+                elif what == 'w':       d=datetime.timedelta(weeks=how_many)
+                elif what == 'm':       d=datetime.timedelta(weeks=4*how_many)
+                return datetime.datetime.utcnow()+d
+
+    # prepare the input for the checks below by
+    # casting strings ('1327098335') to ints
+    if isinstance(input, StringTypes):
+        try:
+            input = int(input)
+        except ValueError:
+            try:
+                new_input=handle_shorthands(input)
+                if new_input is not None: input=new_input
+            except:
+                import traceback
+                traceback.print_exc()
+
+    #################### here we go
+    if isinstance (input, datetime.datetime):
+        #logger.info ("argument to utcparse already a datetime - doing nothing")
+        return input
+    elif isinstance (input, StringTypes):
+        t = dateutil.parser.parse(input)
+        if t.utcoffset() is not None:
+            t = t.utcoffset() + t.replace(tzinfo=None)
+        return t
+    elif isinstance (input, (int,float,long)):
+        return datetime.datetime.fromtimestamp(input)
+    else:
+        logger.error("Unexpected type in utcparse [%s]"%type(input))
+
+def datetime_to_string(dt):
+    return datetime.datetime.strftime(dt, SFATIME_FORMAT)
+
+def datetime_to_utc(dt):
+    return time.gmtime(datetime_to_epoch(dt))
+
+# see https://docs.python.org/2/library/time.html 
+# all timestamps are in UTC so time.mktime() would be *wrong*
+def datetime_to_epoch(dt):
+    return int(calendar.timegm(dt.timetuple()))
+
+def add_datetime(input, days=0, hours=0, minutes=0, seconds=0):
+    """
+    Adjust the input date by the specified delta (in seconds).
+    """
+    dt = utcparse(input)
+    return dt + datetime.timedelta(days=days, hours=hours, minutes=minutes, seconds=seconds)
+
+if __name__ == '__main__':
+        # checking consistency
+    print 20*'X'
+    print ("Should be close to zero: %s"%(datetime_to_epoch(datetime.datetime.utcnow())-time.time()))
+    print 20*'X'
+    for input in [
+            '+2d',
+            '+3w',
+            '+2m',
+            1401282977.575632,
+            1401282977,
+            '1401282977',
+            '2014-05-28',
+            '2014-05-28T15:18',
+            '2014-05-28T15:18:30',
+    ]:
+        print "input=%20s -> parsed %s"%(input,datetime_to_string(utcparse(input)))