class PooledThread(Resource):
def __init__(self, name, release):
Resource.__init__(self, name)
self._release = release
self._ready, self._queue = Event(), InterlockedQueue()
if __name__ == "__main__":
self._timeout = Timeout(3.0)
else:
self._timeout = Timeout(60.0)
self._count = 0
def _expired(self):
return self._timeout.expired or Resource._expired(self)
def connect(self):
Resource.connect(self)
self._thread = LightThread(target=self._thread_proc,
name="{0:s}:?".format(self.name))
self._thread.start()
self._ready.wait(
3.0) # this may spend waiting slightly less, but it's ok
if not self._ready.is_set():
self._queue.push(
exit) # just in case the thread has in fact started
raise Exception("new thread failed to start in 3.0 seconds")
def _thread_proc(self):
self._ready.set()
while True: # exits upon processing of exit pushed in disconnect()
try:
self._count += 1
thread_name = "{0:s}:{1:d}".format(self.name, self._count)
current_thread().name = thread_name
work_unit = self._queue.pop()
work_unit()
self._timeout.reset()
finally:
self._release(
self) # this actually invokes ThreadPool._release
# this method may be called by external thread (ex. pool sweep)
# or by this thread itself, and posts an exit kind of work unit
def disconnect(self):
try:
if current_thread() is not self._thread:
self._queue.push(exit)
self._thread.join(3.0)
finally:
Resource.disconnect(self)
# this method is called by the thread pool to post a work unit
# to this thread, as well as by the thread itself at disconnect
def push(self, work_unit):
self._queue.push(work_unit)
class PooledThread(Resource):
def __init__(self, name, release):
Resource.__init__(self, name)
self._release = release
self._ready, self._queue = Event(), InterlockedQueue()
if __name__ == "__main__":
self._timeout = Timeout(3.0)
else:
self._timeout = Timeout(60.0)
self._count = 0
def _expired(self):
return self._timeout.expired or Resource._expired(self)
def connect(self):
Resource.connect(self)
self._thread = LightThread(target = self._thread_proc,
name = "{0:s}:?".format(self.name))
self._thread.start()
self._ready.wait(3.0) # this may spend waiting slightly less, but it's ok
if not self._ready.is_set():
self._queue.push(exit) # just in case the thread has in fact started
raise Exception("new thread failed to start in 3.0 seconds")
def _thread_proc(self):
self._ready.set()
while True: # exits upon processing of exit pushed in disconnect()
try:
self._count += 1
thread_name = "{0:s}:{1:d}".format(self.name, self._count)
current_thread().name = thread_name
work_unit = self._queue.pop()
work_unit()
self._timeout.reset()
finally:
self._release(self) # this actually invokes ThreadPool._release
# this method may be called by external thread (ex. pool sweep)
# or by this thread itself, and posts an exit kind of work unit
def disconnect(self):
try:
if current_thread() is not self._thread:
self._queue.push(exit)
self._thread.join(3.0)
finally:
Resource.disconnect(self)
# this method is called by the thread pool to post a work unit
# to this thread, as well as by the thread itself at disconnect
def push(self, work_unit):
self._queue.push(work_unit)
def primary_startup(
node_cage: by_regex("^[A-Za-z0-9_-]{1,32}(\\.[A-Za-z0-9_-]{1,32})?$")):
if "." in node_cage: # node name is specified explicitly
node, cage = node_cage.split(".")
else: # node name is taken from the environment
cage = node_cage
node = node_name().split(".")[0]
cage_dir = os_path.join(cages_dir, cage) # cage directory must exist
if not os_path.isdir(cage_dir):
raise Exception("cage directory does not exist")
logs_dir = os_path.join(
cage_dir, "logs") # while logs directory will be created if necessary
if not os_path.isdir(logs_dir):
try:
mkdir(logs_dir)
except OSError as e:
if e.errno != EEXIST:
raise
# write own pid file, this also serves as a test of the logs directory writability
with open(os_path.join(logs_dir, "{0:s}.pid".format(cage)), "wb") as f:
f.write("{0:d}".format(getpid()).encode("ascii"))
restarting_after_failure = False # performing normal startup by default
while True: # keep starting secondary startup script until it exits successfully
def drain_stream(stream):
try:
while stream.read(512):
pass
except:
pass # just exit
# pass the same arguments to the same script, only prefixing them with dash
startup_py = popen(python, os_path.join(pmnc_dir,
"startup.py"), "-", node, cage,
restarting_after_failure and "FAILURE" or "NORMAL")
# any output from the secondary script is ignored
stdout_reader = LightThread(target=drain_stream,
args=(startup_py.stdout, ))
stdout_reader.start()
stderr_reader = LightThread(target=drain_stream,
args=(startup_py.stderr, ))
stderr_reader.start()
# wait for the secondary script to terminate
while startup_py.poll() is None:
try:
sleep(
3.0
) # fails with "interrupted system call" at logoff when started as win32 service
except:
pass
stdout_reader.join(3.0) # should have exited with eof
stderr_reader.join(3.0) # or broken pipe, but who knows
if startup_py.wait() != 0:
restarting_after_failure = True # set the flag and restart the secondary script
else:
break # successful exit
class AdapterHost:
@typecheck
def __init__(self, class_name: str, *,
java: os_path.isfile,
arguments: tuple_of(str),
classpath: str,
jndi: dict_of(str, str),
factory: str,
queue: str,
username: str,
password: str):
# random line prefix and suffix for packet serialization
bol = b2a_hex(urandom(8)).decode("ascii").upper()
eol = b2a_hex(urandom(8)).decode("ascii").upper()
# compose the executable command line
self._args = [ java ] + list(arguments) + \
[ "-classpath", classpath, class_name,
"connection.factory={0:s}".format(factory),
"connection.queue={0:s}".format(queue),
"stdout.bol={0:s}".format(bol),
"stdout.eol={0:s}".format(eol) ]
if username or password:
self._args.append("connection.username={0:s}".format(username))
self._args.append("connection.password={0:s}".format(password))
self._args.extend("jndi.{0:s}={1:s}".format(*t) for t in jndi.items())
self._bol_b = bol.encode("ascii")
self._eol_b = eol.encode("ascii")
# this set tracks messages that have been processed but
# not committed on the server due to a failure
self._processed_messages = set()
###################################
# adapter input from stdin consists of Packet sequence
def _stdin_writer_proc(self, stdin, stdin_queue):
try:
try:
pkt = stdin_queue.pop()
while pkt is not None: # this light thread exits upon None in the queue or exception
pkt.save_to_stream(stdin, 128)
if pkt.get("XPmncResponse") == "COMMIT":
message_id = pkt.pop("XPmncMessageID")
self._processed_messages.remove(message_id)
pkt = stdin_queue.pop()
finally:
stdin.close()
except:
pmnc.log.error(exc_string()) # log and ignore
###################################
# adapter output from stdout consists of Packet sequence
def _stdout_reader_proc(self, stdout, stdin_queue):
try:
try:
try:
pkt = Packet.load_from_stream(stdout, self._bol_b, self._eol_b)
while pkt is not None: # this light thread exits upon eof or exception
self._stdout_queue.push(pkt)
pkt = Packet.load_from_stream(stdout, self._bol_b, self._eol_b)
finally:
stdout.close()
finally:
stdin_queue.push(None) # this releases the associated stdin writer
except:
pmnc.log.error(exc_string()) # log and ignore
###################################
# adapter output from stderr is discarded (yet it has to be read)
def _stderr_reader_proc(self, stderr):
try:
try:
while stderr.read(512): # this light thread exits only upon exception
pass
finally:
stderr.close()
except:
pmnc.log.error(exc_string()) # log and ignore
###################################
# the adapter is considered up until the process exits
def _adapter_running(self):
return self._adapter.poll() is None
###################################
# this method starts the adapter process, creates the handling
# threads and waits for the adapter to report its readiness
def _start_adapter(self, adapter_usage, adapter_name, start_timeout):
pmnc.log.info("starting adapter process for {0:s} {1:s}".\
format(adapter_usage, adapter_name))
if pmnc.log.debug:
pmnc.log.debug("adapter process command line: {0:s}".format(" ".join(self._args)))
self._adapter = popen(*self._args) # start the java process
try:
if pmnc.log.debug:
pmnc.log.debug("adapter process (pid {0:d}) has started".\
format(self._adapter.pid))
# the process has started and its initialization is underway
# create light threads for controlling stdin/out/err, these
# threads are not stopped explicitly but exit when the adapter
# exits and the pipes break
self._stdin_queue = InterlockedQueue()
self._stdin_writer = LightThread(target = self._stdin_writer_proc,
args = (self._adapter.stdin, self._stdin_queue),
name = "{0:s}:stdin".format(adapter_name))
self._stdin_writer.start()
self._stdout_queue = InterlockedQueue()
self._stdout_reader = LightThread(target = self._stdout_reader_proc,
args = (self._adapter.stdout, self._stdin_queue),
name = "{0:s}:stdout".format(adapter_name))
self._stdout_reader.start()
self._stderr_queue = InterlockedQueue()
self._stderr_reader = LightThread(target = self._stderr_reader_proc,
args = (self._adapter.stderr, ),
name = "{0:s}:stderr".format(adapter_name))
self._stderr_reader.start()
# wait for the adapter to come up and report readiness
while not start_timeout.expired:
pkt = self._stdout_queue.pop(min(0.5, start_timeout.remain))
if pkt is None: # see whether the adapter has exited
if not self._adapter_running():
retcode = self._adapter.wait()
if retcode is not None:
raise Exception("adapter process exited with "
"retcode {0:d}".format(retcode))
elif "XPmncError" in pkt:
raise Exception(pkt["XPmncError"])
elif pkt.get("XPmncStatus") == "READY":
break
else:
raise Exception("adapter process returned invalid status")
else:
raise Exception("timeout waiting for adapter process to initialize")
except:
self._stop_adapter(start_timeout) # what remained of start timeout is used for stopping
raise
pmnc.log.info("adapter process (pid {0:d}) is ready".format(self._adapter.pid))
###################################
# if not exited peacefully, adapter has to be killed
def _stop_adapter(self, stop_timeout):
while self._adapter_running() and not stop_timeout.expired:
sleep(min(0.5, stop_timeout.remain))
if self._adapter_running():
pmnc.log.warning("killing runaway adapter process "
"(pid {0:d})".format(self._adapter.pid))
self._adapter.kill()
else:
pmnc.log.info("adapter process (pid {0:d}) exited with retcode {1:d}".\
format(self._adapter.pid, self._adapter.wait()))