| @@ -0,0 +1,295 @@ | |||
| from StringIO import StringIO | |||
| import collections | |||
| import itertools | |||
| import unittest | |||
| class MeterRead(collections.namedtuple('MeterRead', [ 'meterts', 'readts', 'status', 'load', 'maxload', 'loadunit', 'sink', 'source', 'ssunit' ])): | |||
| pass | |||
| class ZoneInfo(collections.namedtuple('ZoneInfo', [ 'tz', 'lcl', 'utc', 'offset' ])): | |||
| def getOffset(self): | |||
| '''Return the offset in seconds from UTC. This value | |||
| should be subtracted from UTC to get localtime or added | |||
| to localtime to get UTC.''' | |||
| off = int(self.offset) | |||
| min = abs(off) % 100 | |||
| hr = int(off / 100) | |||
| return hr * 60 * 60 + min * 60 | |||
| def _pread(fp, off, sz): | |||
| origpos = fp.tell() | |||
| fp.seek(off) | |||
| r = fp.read(sz) | |||
| fp.seek(origpos) | |||
| return r | |||
| # | |||
| # Notes: | |||
| # | |||
| # We are assuming that the first line of the file is in the same timezone | |||
| # as the line that immediately follows. We also assume that the remaining | |||
| # lines in a file are the same timezone. This will be fine as long as no | |||
| # one starts or stops the program around a time change. This is pretty safe | |||
| # in that it only happens twice a year. This is a .023% chance that a | |||
| # random reboot/start of the program will hit this. | |||
| # | |||
| # The meter updates the timezone info when it gets the new info. This | |||
| # means that we don't know exactly when the time changed, BUT there will | |||
| # be a discontinuity, where it skips forward or backward an hour, and this | |||
| # is when the new timezone takes effect. | |||
| class ParseLog(object): | |||
| def __init__(self, fp): | |||
| self._fp = fp | |||
| @staticmethod | |||
| def parseline(data, tz=None): | |||
| p = data.split() | |||
| if p[0] == 'm': | |||
| if tz is None: | |||
| raise ValueError('cannot parse meter line w/o timezone info') | |||
| meterts = int(p[2]) - tz.getOffset() | |||
| return MeterRead(meterts=meterts, readts=float(p[1]), | |||
| status=p[3], load=float(p[4]), maxload=float(p[5]), | |||
| loadunit=p[6], sink=float(p[7]), | |||
| source=float(p[8]), ssunit=p[9]) | |||
| elif p[0] == 'z': | |||
| return ZoneInfo(p[1], int(p[2]), int(p[3]), p[4]) | |||
| else: | |||
| raise ValueError('unknown type: %s' % repr(data[0])) | |||
| def __iter__(self): | |||
| # this can be suspended/resumed between yields, so | |||
| # keep track of pointer. | |||
| fp = self._fp | |||
| pos = 0 | |||
| tz = None | |||
| done = False | |||
| while not done: | |||
| fp.seek(pos) | |||
| pendinglines = [] | |||
| # find the timezone info | |||
| while True: | |||
| l = fp.readline() | |||
| if l == '': | |||
| done = True | |||
| break | |||
| elif l[0] == 'z': | |||
| nexttz = self.parseline(l) | |||
| if tz is None: | |||
| tz = nexttz | |||
| else: | |||
| pendinglines.append(l) | |||
| pos = fp.tell() | |||
| # was there a tz change | |||
| tzchange = tz.offset != nexttz.offset | |||
| lastts = None | |||
| for idx, i in enumerate(pendinglines): | |||
| line = self.parseline(i, tz) | |||
| if (tzchange and lastts is not None and | |||
| abs(line.meterts - lastts) > 50*60): | |||
| tz = nexttz | |||
| # need to reparse due to zone changed | |||
| line = self.parseline(i, tz) | |||
| tzchange = False | |||
| yield line | |||
| lastts = line.meterts | |||
| @staticmethod | |||
| def verifyIndex(idx, fp): | |||
| origpos = fp.tell() | |||
| # check size | |||
| fp.seek(0, 2) # End of file | |||
| length = fp.tell() == idx['length'] | |||
| fp.seek(origpos) | |||
| return all(itertools.chain((length,), (_pread(fp, x[1], 1) == 'z' for x in idx['index']))) | |||
| @staticmethod | |||
| def generateIndex(fp, bufsize=65536): | |||
| origpos = fp.tell() | |||
| fp.seek(0, 2) # End of file | |||
| idxs = [] | |||
| ret = dict(length=fp.tell(), index=idxs) | |||
| pos = 0 | |||
| fp.seek(0) | |||
| prebuf = '' | |||
| while True: | |||
| buf = prebuf + fp.read(bufsize) | |||
| if buf == '': | |||
| break | |||
| cont = False | |||
| zpos = 0 | |||
| while True: | |||
| try: | |||
| idx = buf.index('z', zpos) | |||
| except ValueError: | |||
| break | |||
| try: | |||
| nl = buf.index('\n', idx) | |||
| except ValueError: | |||
| prebuf = buf | |||
| cont = True | |||
| break | |||
| line = ParseLog.parseline(buf[idx:nl], None) | |||
| idxs.append((line.utc, pos + idx)) | |||
| zpos = nl + 1 | |||
| if cont: | |||
| continue | |||
| pos += bufsize + len(prebuf) | |||
| prebuf = '' | |||
| # restore position | |||
| fp.seek(origpos) | |||
| return ret | |||
| @classmethod | |||
| def fromfile(cls, fp): | |||
| '''Pass in a file like object that is the log. | |||
| Note that this will claim ownership of the file object. It | |||
| may seek and read parts of the file, the fp should not be | |||
| accessed after this call. When the object is destroyed, it | |||
| will be closed. | |||
| ''' | |||
| return cls(fp) | |||
| class MiscTests(unittest.TestCase): | |||
| def test_pread(self): | |||
| s = 'this is a random test string' | |||
| sio = StringIO(s) | |||
| pos = 13 | |||
| sio.seek(pos) | |||
| self.assertEqual(_pread(sio, 10, 4), s[10:10 + 4]) | |||
| self.assertEqual(_pread(sio, 7, 1), s[7]) | |||
| self.assertEqual(sio.tell(), pos) | |||
| class Tests(unittest.TestCase): | |||
| oldlines = '''l 1571848576 Connected 1.1260 9.155000 W 65375.946 0.000 Wh | |||
| z GMT+7 1571848569 1571873769 -0700 | |||
| l 1571848585 Connected 1.0890 9.155000 kW 15.946 0.000 kWh | |||
| l 1571848593 Connected 1.0500 9.155000 kW 15.946 0.000 kWh | |||
| ''' | |||
| def test_getoffset(self): | |||
| zi = ZoneInfo(tz='GMT+8', lcl='1577132476', utc='1577161276', offset='-0800') | |||
| self.assertEqual(zi.getOffset(), -8 * 60 * 60) | |||
| zi = ZoneInfo(tz='GMT+8', lcl='1577132476', utc='1577161276', offset='-0700') | |||
| self.assertEqual(zi.getOffset(), -7 * 60 * 60) | |||
| zi = ZoneInfo(tz='GMT+8', lcl='1577132476', utc='1577161276', offset='-0730') | |||
| self.assertEqual(zi.getOffset(), -(7 * 60 * 60 + 30 * 60)) | |||
| # notes: | |||
| # 1572767994 Sun Nov 3 00:59:54 PDT 2019 | |||
| # 1572768005 Sun Nov 3 01:00:05 PDT 2019 | |||
| # 1572771545 Sun Nov 3 01:59:05 PDT 2019 | |||
| # 1572772464 Sun Nov 3 01:14:24 PST 2019 | |||
| # 1572772472 Sun Nov 3 01:14:32 PST 2019 | |||
| # 1572775140 Sun Nov 3 01:59:00 PST 2019 | |||
| # 1572778799 Sun Nov 3 02:59:59 PST 2019 | |||
| # 1572793200 Sun Nov 3 07:00:00 PST 2019 | |||
| # 1572793208 Sun Nov 3 07:00:08 PST 2019 | |||
| zonelines = '''m 1572767994.3 1572742790 Connected 0 0 kW 0 0 kWh | |||
| z GMT+7 1572742795 1572767995 -0700 | |||
| m 1572768005.3 1572742805 Connected 0 0 kW 0 0 kWh | |||
| m 1572769505.3 1572744305 Connected 0 0 kW 0 0 kWh | |||
| m 1572771545.3 1572746345 Connected 0 0 kW 0 0 kWh | |||
| m 1572772464.3 1572747264 Connected 0 0 kW 0 0 kWh | |||
| m 1572772472.3 1572743672 Connected 0 0 kW 0 0 kWh | |||
| m 1572775140.3 1572746340 Connected 0 0 kW 0 0 kWh | |||
| m 1572778799.3 1572749999 Connected 0 0 kW 0 0 kWh | |||
| z GMT+8 1572750100 1572778900 -0800 | |||
| m 1572793208.3 1572764405 Connected 0 0 kW 0 0 kWh | |||
| ''' | |||
| def test_zonemove(self): | |||
| # test when DST moves | |||
| s = StringIO(self.zonelines) | |||
| pl = ParseLog.fromfile(s) | |||
| lines = list(pl) | |||
| self.assertEqual([ x.meterts for x in lines ], [ 1572767990, 1572768005, 1572769505, 1572771545, 1572772464, 1572772472, 1572775140, 1572778799, 1572793205 ]) | |||
| def test_genverifindex(self): | |||
| s = StringIO(self.zonelines) | |||
| pos = 10 | |||
| s.seek(pos) | |||
| genidx = ParseLog.generateIndex(s, 2) | |||
| zpos = [ i for i, x in enumerate(self.zonelines) if x == 'z' ] | |||
| # that the position remained the same | |||
| self.assertEqual(s.tell(), pos) | |||
| self.assertEqual(genidx['length'], len(s.getvalue())) | |||
| self.assertEqual(genidx['index'], [ (1572767995, zpos[0]), (1572778900, zpos[1]) ]) | |||
| self.assertTrue(ParseLog.verifyIndex(genidx, s)) | |||
| s.seek(pos) | |||
| tmp = genidx.copy() | |||
| tmp['length'] = 0 | |||
| self.assertFalse(ParseLog.verifyIndex(tmp, s)) | |||
| tmp = genidx.copy() | |||
| tmp['index'][0] = (tmp['index'][0][0], 10) | |||
| self.assertFalse(ParseLog.verifyIndex(tmp, s)) | |||
| # that the position remained the same | |||
| self.assertEqual(s.tell(), pos) | |||
| newlines = '''m 1577161278.22 1577132472 Connected 0.2580 1.992000 kW 90.404 1.660 kWh | |||
| z GMT+8 1577132476 1577161276 -0800 | |||
| m 1577161288.39 1577132480 Connected 0.3410 1.992000 kW 90.404 1.660 kWh | |||
| m 1577161298.96 1577132488 Connected 0.1450 1.992000 kW 90.404 1.660 kWh | |||
| ''' | |||
| def test_parsenew(self): | |||
| s = StringIO(self.newlines) | |||
| pl = ParseLog.fromfile(s) | |||
| lines = list(pl) | |||
| self.assertEqual([ x.readts for x in lines ], [ 1577161278.22, 1577161288.39, 1577161298.96 ]) | |||
| self.assertEqual([ x.meterts for x in lines ], [ 1577161272, 1577161280, 1577161288 ]) | |||
| self.assertEqual([ x.load for x in lines ], [ 0.2580, 0.3410, 0.1450 ]) | |||
| def test_close(self): | |||
| # test to make sure the file object is closed | |||
| pass | |||