import time, logging, sys, traceback, os, shutil, io
from threading import Thread

testdurationsecs = 10
threadcount = 4
linesperiteration = 50


log = logging.getLogger('mylogger')
log.setLevel(logging.INFO)

logging.getLogger().addHandler(logging.NullHandler())

OUTPUT_DIR = 'output-logger-race'
if os.path.exists(OUTPUT_DIR): shutil.rmtree(OUTPUT_DIR)
os.makedirs(OUTPUT_DIR)

endtime = time.time()+testdurationsecs

def mythread(threadid):
	try:
		it = 0
		while time.time()< endtime:
			it += 1
			filenames = [OUTPUT_DIR+'/thread-%s-it%05d-A.log'%(threadid, it)]


			h1 = logging.FileHandler(filenames[0])
			log.addHandler(h1)
			
			s2 = io.StringIO()
			h2 = logging.StreamHandler(s2)
			log.addHandler(h2)
				
			for i in range(linesperiteration):
				log.info('Log line: thread-%s %04d.'%(threadid, i+1))
			
			# removing handlers on this thread can mess up callHandlers() from other threads
			log.removeHandler(h1)
			log.removeHandler(h2)
		
			# check all lines were written
			errors = []
			for fn in filenames:
				with open(fn) as f:
					contents = f.read()
					for i in range(linesperiteration):
						if ('Log line: thread-%s %04d.'%(threadid, i+1)) not in contents:
							errors.append('%s is missing line %d'%(fn, i))
			if errors: 
				sys.stderr.write('%d errors: %s\n'%(len(errors), '\n  '.join(errors)))
				#raise Exception('Got %d errors: %s\n'%(len(errors), '\n  '.join(errors)))
			for fn in filenames:
				try:
					os.remove(fn)
				except Exception: # try to cleanup, but windows file locking means this sometimes fails, and don't care
					pass
			#if not errors: sys.stderr.write('PASSED - %s iteration %s\n'%(threadid, it))
						
		print('Thread finished after %d iterations'%it)
	except Exception as e:
		sys.stderr.write('\n%s Failed with exception: %s\n'%(threadid, repr(e)))
		traceback.print_exc()
		sys.exit(100)
		
for t in range(threadcount):
	t = Thread(target = mythread, args=['thread%02d'%(t+1)])
	t.start()