[reassembler] improve timestamp handling with timezones

iridiumtk/reassembler/id_sat_map.py

@@ -3,6 +3,7 @@
 
 import sys
 import datetime
+from util import dt
 
 from .base import *
 from .ira import ReassembleIRA
@@ -81,8 +82,7 @@ def find_closest_satellite(self, t, xyz, satlist):
         return closest_satellite, closest_distance
 
     def process(self,q):
-        time = datetime.datetime.utcfromtimestamp(q.time)
-        time = time.replace(tzinfo=utc)
+        time = dt.epoch(q.time)
         t = self.ts.utc(time)
         if self.first:
             self.first=False
@@ -106,8 +106,10 @@ def process(self,q):
 
     def consume(self,q):
         if config.verbose:
-#            print("%s: sat %02d beam %02d [%d %4.2f %4.2f %s] matched %-20s @ %5.2f°"%( datetime.datetime.utcfromtimestamp(q.time), q.sat,q.beam,q.time,q.lat,q.lon,q.alt,q.name,q.sep))
-            print("%s: sat %02d beam %02d [%d %8.4f %8.4f %s] matched %-20s @ %5fkm"%( datetime.datetime.utcfromtimestamp(q.time), q.sat,q.beam,q.time,q.lat,q.lon,q.alt,q.name,q.sep))
+            #print("%s: sat %02d beam %02d [%d %8.2f %8.2f %s] matched %-20s @ %5.2f°" %
+            print("%s: sat %02d beam %02d [%d %8.4f %8.4f %s] matched %-20s @ %5fkm" %
+                  (dt.epoch(q.time), q.sat, q.beam, q.time, q.lat, q.lon, q.alt, q.name, q.sep))
+
         if q.sep > self.MAX_DIST:
             q.name="NONE"
         if not q.sat in self.sats:

iridiumtk/reassembler/ira.py

@@ -3,6 +3,7 @@
 
 import sys
 import re
+from util import dt
 
 from .base import *
 from ..config import config, outfile
@@ -35,7 +36,7 @@ def filter(self,line):
                 return q
     def process(self,q):
         q.enrich()
-        strtime=datetime.datetime.fromtimestamp(q.time,tz=Z).strftime("%Y-%m-%dT%H:%M:%S.{:02.0f}Z".format(int((q.time%1)*100)))
+        strtime = dt.epoch(q.time).isoformat(timespec='centiseconds')
         for x in q.pages:
             return ["%s %03d %02d %6.2f %6.2f %03d : %s %s"%(strtime, q.sat,q.beam,q.lat,q.lon,q.alt,x[0],x[1])]
     def consume(self,q):

iridiumtk/reassembler/iratime.py

@@ -4,11 +4,13 @@
 import sys
 import re
 import collections
+from util import dt
 
 from .base import *
 from ..config import config, outfile
 
 class ReassembleIRATime(Reassemble):
+    """Check if there are IRA for the same beam quicker than 4.2 seconds"""
     def __init__(self):
         pass
     def filter(self,line):
@@ -32,7 +34,7 @@ def filter(self,line):
     def process(self,q):
         if q.beam in self.buf[q.sat]:
             if q.time-self.buf[q.sat][q.beam] < 4.2:
-                strtime=datetime.datetime.fromtimestamp(q.time,tz=Z).strftime("%Y-%m-%dT%H:%M:%S")
+                strtime = dt.epoch(q.time).isoformat(timespec='seconds')
                 print("%3d %3d: %s %f"%(q.beam,q.sat,strtime,q.time-self.buf[q.sat][q.beam]))
 
         self.buf[q.sat][q.beam]=q.time

iridiumtk/reassembler/msg.py

@@ -4,7 +4,7 @@
 import sys
 import datetime
 import re
-from util import to_ascii, slice_extra
+from util import to_ascii, slice_extra, dt
 
 from .base import *
 from ..config import config, outfile
@@ -179,7 +179,7 @@ def consume(self, msg):
             if not msg.correct:
                 return
 
-        date= datetime.datetime.fromtimestamp(msg.time).strftime("%Y-%m-%dT%H:%M:%S")
+        date = dt.epoch_local(msg.time).isoformat(timespec='seconds')
         str="Message %07d %02d @%s (len:%d)"%(msg.ric, msg.seq, date, msg.pcnt)
         txt= msg.content
         if 'noburst' in config.args:

iridiumtk/reassembler/pktstats.py

@@ -4,6 +4,7 @@
 import sys
 import datetime
 from copy import deepcopy
+from util import dt
 
 from .base import *
 from ..config import config, outfile, state
@@ -81,9 +82,9 @@ def printstats(self, timeslot, stats, skip=False):
         comment=''
         if skip:
             comment='#!'
-            print("#!@ %s L:"%(datetime.datetime.fromtimestamp(ts)), file=sys.stderr)
+            print("#!@ %s L:"%(dt.epoch_local(ts)), file=sys.stderr)
         else:
-            print("# @ %s L:"%(datetime.datetime.fromtimestamp(ts)), file=sys.stderr)
+            print("# @ %s L:"%(dt.epoch_local(ts)), file=sys.stderr)
         for k in stats:
             for t in stats[k]:
                 print("%siridium.parsed.%s.%s %7d %8d"%(comment,k,t,stats[k][t],ts))

iridiumtk/reassembler/ppm.py

@@ -9,7 +9,7 @@
 import os
 import socket
 from copy import deepcopy
-from util import fmt_iritime, to_ascii, slice_extra
+from util import fmt_iritime, to_ascii, slice_extra, dt
 
 from .base import *
 from ..config import config, outfile
@@ -40,13 +40,13 @@ def filter(self,line):
         m=self.r2.match(q.data)
         if not m: return
         if m.group(2):
-            q.itime = datetime.datetime.strptime(m.group(1), '%Y-%m-%dT%H:%M:%S.%f')
+            q.itime = dt.strptime(m.group(1), '%Y-%m-%dT%H:%M:%S.%f').replace(tzinfo=datetime.timezone.utc)
         else:
-            q.itime = datetime.datetime.strptime(m.group(1), '%Y-%m-%dT%H:%M:%S')
+            q.itime = dt.strptime(m.group(1), '%Y-%m-%dT%H:%M:%S').replace(tzinfo=datetime.timezone.utc)
         return q
 
     def process(self,q):
-        q.uxtime=datetime.datetime.utcfromtimestamp(q.time)
+        q.uxtime = dt.epoch(q.time)
 
         # correct for slot:
         # 1st vs. 4th slot is 3 * (downlink + guard)
@@ -93,7 +93,7 @@ def consume(self, data):
         if (data[1]-self.cur[1]).total_seconds() > 600:
             (irun,toff,ppm)=self.onedelta(self.cur,data, verbose=False)
             if 'grafana' in config.args:
-                print("iridium.live.ppm %.5f %d"%(ppm,(data[1]-datetime.datetime.fromtimestamp(0)).total_seconds()))
+                print("iridium.live.ppm %.5f %d" % (ppm, data[1].timestamp()))
                 sys.stdout.flush()
             else:
                 print("@ %s: ppm: % 6.3f ds: % 8.5f "%(data[1],ppm,(data[1]-data[0]).total_seconds()))

iridiumtk/reassembler/sbd.py

@@ -4,7 +4,7 @@
 import sys
 import datetime
 import re
-from util import to_ascii
+from util import to_ascii, dt
 
 from .base import *
 from .ida import ReassembleIDA
@@ -210,11 +210,11 @@ def consume_l2(self,q):
 
         if len(q.data)>0:
             print("%s %-99s %s | %s"%(
-                        datetime.datetime.fromtimestamp(q.time).strftime("%Y-%m-%dT%H:%M:%S"),
+                        dt.epoch_local(int(q.time)).isoformat(),
                         hdr,q.data.hex(" "),to_ascii(q.data, dot=True)), file=outfile)
         else:
             print("%s %s"%(
-                        datetime.datetime.fromtimestamp(q.time).strftime("%Y-%m-%dT%H:%M:%S"),
+                        dt.epoch_local(int(q.time)).isoformat(),
                         hdr), file=outfile)
 
 acars_labels={ # ref. http://www.hoka.it/oldweb/tech_info/systems/acarslabel.htm

util.py

@@ -189,3 +189,48 @@ def parse_channel(fstr):
     else:
         frequency=int(fstr)
     return int(frequency)
+
+class dt(datetime.datetime):
+    def isoformat(self, sep='T', timespec='auto'):
+        """Return the time formatted according to ISO.
+
+        The full format looks like 'YYYY-MM-DD HH:MM:SS.mmmmmm'.
+        By default, the fractional part is omitted if self.microsecond == 0
+        or shortened to 'YYYY-MM-DD HH:MM:SS.mmm' if possible.
+
+        If self.tzinfo is not None, the UTC offset is also attached, giving
+        giving a full format of 'YYYY-MM-DD HH:MM:SS.mmmmmm+HHMM'.
+
+        if the UTC offset is 0, a 'Z' will be used, so the format is
+        shortened to 'YYYY-MM-DD HH:MM:SS.mmmmmmZ'.
+
+        Optional arguments exist for compability but should not be used.
+        """
+
+        if self.microsecond != 0 and self.microsecond % 1000 == 0 and timespec == 'auto':
+            timespec = 'milliseconds'
+
+        trunc = False
+        if timespec == 'centiseconds':
+            timespec = 'milliseconds'
+            trunc = True
+
+        _iso = super().isoformat(sep, timespec)
+
+        if trunc and _iso[-6] == '+' and _iso[-10] == '.':
+            _iso = _iso[:-7] + _iso[-6:]
+        if _iso[-6:] == '+00:00':
+            _iso = _iso[:-6] + 'Z'
+        if (_iso[-6] == '+' or _iso[-6] == '-') and _iso[-3] == ':':
+            _iso = _iso[:-3] + _iso[-2:]
+        return _iso
+
+    @classmethod
+    def epoch(cls, t):
+        """Construct a correct UTC datetime from a POSIX timestamp."""
+        return cls.fromtimestamp(t, datetime.timezone.utc)
+
+    @classmethod
+    def epoch_local(cls, t):
+        """Construct a datetime from a POSIX timestamp in the local timezone."""
+        return cls.fromtimestamp(t, datetime.timezone.utc).astimezone()