Always create creationTime & updateTime, default to Unix epoch

src/cal_tools/files.py

 
-from datetime import datetime
+from datetime import datetime, timezone
 from itertools import chain
 from numbers import Integral
 from pathlib import Path
@@ -310,14 +310,20 @@ class DataFile(h5py.File):
             if sequence is None:
                 sequence = self.__sequence
 
+        if creation_date is None:
+            creation_date = datetime.fromtimestamp(0, tz=timezone.utc)
+        elif creation_date is True:
+            creation_date = datetime.now(timezone.utc)
+
         if update_date is None:
             update_date = creation_date
+        elif update_date is True:
+            update_date = datetime.now(timezone.utc)
 
         md_group = self.require_group('METADATA')
-        if creation_date is not None:
-            md_group.create_dataset(
-                'creationDate', shape=(1,),
-                data=creation_date.strftime('%Y%m%dT%H%M%SZ').encode('ascii'))
+        md_group.create_dataset(
+            'creationDate', shape=(1,),
+            data=creation_date.strftime('%Y%m%dT%H%M%SZ').encode('ascii'))
         md_group.create_dataset('daqLibrary', shape=(1,),
                                 data=daq_library.encode('ascii'))
         md_group.create_dataset('dataFormatVersion', shape=(1,), data=b'1.2')
@@ -358,10 +364,9 @@ class DataFile(h5py.File):
             'runNumber', shape=(1,), dtype=np.uint32, data=run)
         md_group.create_dataset(
             'sequenceNumber', shape=(1,), dtype=np.uint32, data=sequence)
-        if update_date is not None:
-            md_group.create_dataset(
-                'updateDate', shape=(1,),
-                data=update_date.strftime('%Y%m%dT%H%M%SZ').encode('ascii'))
+        md_group.create_dataset(
+            'updateDate', shape=(1,),
+            data=update_date.strftime('%Y%m%dT%H%M%SZ').encode('ascii'))
 
 
 class ControlSource(h5py.Group):