1 files changed, 84 insertions, 0 deletions
diff --git a/trove/common/timeutils.py b/trove/common/timeutils.py
new file mode 100644
index 00000000..44a0b9ff
--- /dev/null
+++ b/trove/common/timeutils.py
@@ -0,0 +1,84 @@
+# Copyright 2016 Tesora Inc.
+# All Rights Reserved.
+#
+#    Licensed under the Apache License, Version 2.0 (the "License"); you may
+#    not use this file except in compliance with the License. You may obtain
+#    a copy of the License at
+#
+#         http://www.apache.org/licenses/LICENSE-2.0
+#
+#    Unless required by applicable law or agreed to in writing, software
+#    distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
+#    WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
+#    License for the specific language governing permissions and limitations
+#    under the License.
+
+from datetime import datetime
+from datetime import timedelta
+from datetime import tzinfo
+
+
+class zulutime(tzinfo):
+    """A tzinfo class for zulu time"""
+
+    def utcoffset(self, dt):
+        return timedelta(0)
+
+    def tzname(self, dt):
+        return "Z"
+
+    def dst(self, dt):
+        return timedelta(0)
+
+
+def utcnow_aware():
+    """An aware utcnow() that uses zulutime for the tzinfo."""
+    return datetime.now(zulutime())
+
+
+def utcnow():
+    """A wrapper around datetime.datetime.utcnow(). We're doing this
+       because it is mock'ed in some places.
+    """
+    return datetime.utcnow()
+
+
+def isotime(tm=None, subsecond=False):
+    """Stringify a time and return it in an ISO 8601 format. Subsecond
+       information is only provided if the subsecond parameter is set
+       to True (default: False).
+
+       If a time (tm) is provided, it will be stringified. If tm is
+       not provided, the current UTC time is used instead.
+
+       The timezone for UTC time will be provided as 'Z' and not
+       [+-]00:00. Time zone differential for non UTC times will be
+       provided as the full six character string format provided by
+       datetime.datetime.isoformat() namely [+-]NN:NN.
+
+       If an invalid time is provided such that tm.utcoffset() causes
+       a ValueError, that exception will be propagated.
+    """
+
+    _dt = tm if tm else utcnow_aware()
+
+    if not subsecond:
+        _dt = _dt.replace(microsecond=0)
+
+    # might cause an exception if _dt has a bad utcoffset.
+    delta = _dt.utcoffset() if _dt.utcoffset() else timedelta(0)
+
+    ts = None
+
+    if delta == timedelta(0):
+        # either we are provided a naive time (tm) or no tm, or an
+        # aware UTC time. In any event, we want to use 'Z' for the
+        # timezone rather than the full 6 character offset.
+        _dt = _dt.replace(tzinfo=None)
+        ts = _dt.isoformat()
+        ts += 'Z'
+    else:
+        # an aware non-UTC time was provided
+        ts = _dt.isoformat()
+
+    return ts