epicyon/threads.py

155 lines
4.6 KiB
Python

__filename__ = "threads.py"
__author__ = "Bob Mottram"
__license__ = "AGPL3+"
__version__ = "1.2.0"
__maintainer__ = "Bob Mottram"
__email__ = "bob@libreserver.org"
__status__ = "Production"
__module_group__ = "Core"
import threading
import sys
import time
import datetime
class threadWithTrace(threading.Thread):
def __init__(self, *args, **keywords):
self.startTime = datetime.datetime.utcnow()
self.isStarted = False
tries = 0
while tries < 3:
try:
self._args, self._keywords = args, keywords
threading.Thread.__init__(self, *self._args, **self._keywords)
self.killed = False
break
except Exception as e:
print('ERROR: threads.py/__init__ failed - ' + str(e))
time.sleep(1)
tries += 1
def start(self):
tries = 0
while tries < 3:
try:
self.__run_backup = self.run
self.run = self.__run
threading.Thread.start(self)
break
except Exception as e:
print('ERROR: threads.py/start failed - ' + str(e))
time.sleep(1)
tries += 1
# note that this is set True even if all tries failed
self.isStarted = True
def __run(self):
sys.settrace(self.globaltrace)
try:
self.__run_backup()
self.run = self.__run_backup
except Exception as e:
print('ERROR: threads.py/__run failed - ' + str(e))
pass
def globaltrace(self, frame, event, arg):
if event == 'call':
return self.localtrace
else:
return None
def localtrace(self, frame, event, arg):
if self.killed:
if event == 'line':
raise SystemExit()
return self.localtrace
def kill(self):
self.killed = True
def clone(self, fn):
return threadWithTrace(target=fn,
args=self._args,
daemon=True)
def removeDormantThreads(baseDir: str, threadsList: [], debug: bool,
timeoutMins: int) -> None:
"""Removes threads whose execution has completed
"""
if len(threadsList) == 0:
return
timeoutSecs = int(timeoutMins * 60)
dormantThreads = []
currTime = datetime.datetime.utcnow()
changed = False
# which threads are dormant?
noOfActiveThreads = 0
for th in threadsList:
removeThread = False
if th.isStarted:
if not th.is_alive():
if (currTime - th.startTime).total_seconds() > 10:
if debug:
print('DEBUG: ' +
'thread is not alive ten seconds after start')
removeThread = True
# timeout for started threads
if (currTime - th.startTime).total_seconds() > timeoutSecs:
if debug:
print('DEBUG: started thread timed out')
removeThread = True
else:
# timeout for threads which havn't been started
if (currTime - th.startTime).total_seconds() > timeoutSecs:
if debug:
print('DEBUG: unstarted thread timed out')
removeThread = True
if removeThread:
dormantThreads.append(th)
else:
noOfActiveThreads += 1
if debug:
print('DEBUG: ' + str(noOfActiveThreads) +
' active threads out of ' + str(len(threadsList)))
# remove the dormant threads
dormantCtr = 0
for th in dormantThreads:
if debug:
print('DEBUG: Removing dormant thread ' + str(dormantCtr))
dormantCtr += 1
threadsList.remove(th)
th.kill()
changed = True
# start scheduled threads
if len(threadsList) < 10:
ctr = 0
for th in threadsList:
if not th.isStarted:
print('Starting new send thread ' + str(ctr))
th.start()
changed = True
break
ctr += 1
if not changed:
return
if debug:
sendLogFilename = baseDir + '/send.csv'
try:
with open(sendLogFilename, 'a+') as logFile:
logFile.write(currTime.strftime("%Y-%m-%dT%H:%M:%SZ") +
',' + str(noOfActiveThreads) +
',' + str(len(threadsList)) + '\n')
except OSError:
print('EX: removeDormantThreads unable to write ' +
sendLogFilename)