Prépare l'utilisation de generalized time format pour recuPaiement

* Et de datetimes timezone aware pour gérer le bousin

gestion/ldap_crans.py

@@ -47,6 +47,16 @@ import ridtools
 from user_tests import isadm
 import getpass
 
+try:
+    import pytz
+except:
+    pytz = None
+
+try:
+    import dateutil.tz
+except:
+    dateutil = None
+
 cur_user = os.getenv("SUDO_USER") or os.getenv("USER") or os.getenv("LOGNAME") or getpass.getuser()
 
 date_format = '%d/%m/%Y %H:%M'
@@ -163,6 +173,60 @@ def fromGeneralizedTimeFormat(gtf):
     """
     return time.mktime(time.strptime(gtf.split("-", 1)[0].split("+", 1)[0].split('Z', 1)[0], "%Y%m%d%H%M%S"))
 
+def datetimeFromGTF(gtf):
+    """Returns a datetime from generalized time format
+
+    """
+    if '-' in gtf or '+' in gtf:
+        date, tz = gtf[0:14], gtf[14:]
+    else:
+        date = gtf.replace("Z", '')
+        tz = '+0000'
+    return localizedDatetime(date, tz)
+
+def datetimeToGTF(datetime_obj):
+    """Transforms a datetime to a GTF"""
+    to_append = ""
+    if datetime_obj.utcoffset() is None:
+        if pytz is not None:
+            datetime_obj = pytz.utc.localize(datetime_obj)
+        else:
+            to_append = "Z"
+    mostly_gtf = datetime.datetime.strftime(datetime_obj, "%Y%m%d%H%M%S%z")
+    return mostly_gtf.replace('+0000', "Z") + to_append
+
+def localizedDatetime(date=None, tz=None):
+    """Génère un datetime localisé à partir d'une chaîne de la forme
+    %Y%m%d%H%M%S, et d'une chaîne tz de la forme +0200"""
+
+    _notz = (tz is None)
+
+    if date is not None:
+        the_date = datetime.datetime.strptime(date, "%Y%m%d%H%M%S")
+    else:
+        the_date = datetime.datetime.now()
+
+    # No timezone means we try to get from the system
+    # if we have dateutil, else, UTC.
+    if tz is None:
+        if dateutil is not None:
+            tz = datetime.datetime.now(dateutil.tz.tzlocal()).strftime("%z")
+        else:
+            tz = "+0000"
+
+    # No pytz means no timezoned datetime
+    if pytz is not None:
+        the_timezone = pytz.FixedOffset(int(tz[0:-2])*60 + int(tz[-2:]))
+        the_date = the_timezone.localize(the_date)
+        the_date = the_timezone.normalize(the_date)
+    else:
+        # Maybe we can do something
+        if dateutil is not None:
+            if _notz:
+                the_date.replace(tzinfo=dateutil.tz.tzlocal())
+
+    return the_date
+
 def strip_accents(a, sois_un_porc_avec_les_espaces = True):
     """ Supression des accents de la chaîne fournie """
     res = normalize('NFKD', decode(a)).encode('ASCII', 'ignore')