class ZMQPoller(object):
"""A poller that can be used in the tornado IOLoop.
This simply wraps a regular zmq.Poller, scaling the timeout
by 1000, so that it is in seconds rather than milliseconds.
"""
def __init__(self):
self._poller = Poller()
@staticmethod
def _map_events(events):
"""translate IOLoop.READ/WRITE/ERROR event masks into zmq.POLLIN/OUT/ERR"""
z_events = 0
if events & IOLoop.READ:
z_events |= POLLIN
if events & IOLoop.WRITE:
z_events |= POLLOUT
if events & IOLoop.ERROR:
z_events |= POLLERR
return z_events
@staticmethod
def _remap_events(z_events):
"""translate zmq.POLLIN/OUT/ERR event masks into IOLoop.READ/WRITE/ERROR"""
events = 0
if z_events & POLLIN:
events |= IOLoop.READ
if z_events & POLLOUT:
events |= IOLoop.WRITE
if z_events & POLLERR:
events |= IOLoop.ERROR
return events
def register(self, fd, events):
return self._poller.register(fd, self._map_events(events))
def modify(self, fd, events):
return self._poller.modify(fd, self._map_events(events))
def unregister(self, fd):
return self._poller.unregister(fd)
def poll(self, timeout):
"""poll in seconds rather than milliseconds.
Event masks will be IOLoop.READ/WRITE/ERROR
"""
z_events = self._poller.poll(1000*timeout)
return [ (fd,self._remap_events(evt)) for (fd,evt) in z_events ]
def close(self):
pass
class ZMQPoller(object):
"""A poller that can be used in the tornado IOLoop.
This simply wraps a regular zmq.Poller, scaling the timeout
by 1000, so that it is in seconds rather than milliseconds.
"""
def __init__(self):
self._poller = Poller()
@staticmethod
def _map_events(events):
"""translate IOLoop.READ/WRITE/ERROR event masks into zmq.POLLIN/OUT/ERR"""
z_events = 0
if events & IOLoop.READ:
z_events |= POLLIN
if events & IOLoop.WRITE:
z_events |= POLLOUT
if events & IOLoop.ERROR:
z_events |= POLLERR
return z_events
@staticmethod
def _remap_events(z_events):
"""translate zmq.POLLIN/OUT/ERR event masks into IOLoop.READ/WRITE/ERROR"""
events = 0
if z_events & POLLIN:
events |= IOLoop.READ
if z_events & POLLOUT:
events |= IOLoop.WRITE
if z_events & POLLERR:
events |= IOLoop.ERROR
return events
def register(self, fd, events):
return self._poller.register(fd, self._map_events(events))
def modify(self, fd, events):
return self._poller.modify(fd, self._map_events(events))
def unregister(self, fd):
return self._poller.unregister(fd)
def poll(self, timeout):
"""poll in seconds rather than milliseconds.
Event masks will be IOLoop.READ/WRITE/ERROR
"""
z_events = self._poller.poll(1000*timeout)
return [ (fd,self._remap_events(evt)) for (fd,evt) in z_events ]
def close(self):
pass
class ZmqSelector(BaseSelector):
"""A selector that can be used with asyncio's selector base event loops."""
def __init__(self):
# this maps file descriptors to keys
self._fd_to_key = {}
# read-only mapping returned by get_map()
self._map = _SelectorMapping(self)
self._poller = ZMQPoller()
def _fileobj_lookup(self, fileobj):
"""Return a file descriptor from a file object.
This wraps _fileobj_to_fd() to do an exhaustive search in case
the object is invalid but we still have it in our map. This
is used by unregister() so we can unregister an object that
was previously registered even if it is closed. It is also
used by _SelectorMapping.
"""
try:
return _fileobj_to_fd(fileobj)
except ValueError:
# Do an exhaustive search.
for key in self._fd_to_key.values():
if key.fileobj is fileobj:
return key.fd
# Raise ValueError after all.
raise
def register(self, fileobj, events, data=None):
if (not events) or (events & ~(EVENT_READ | EVENT_WRITE)):
raise ValueError("Invalid events: {!r}".format(events))
key = SelectorKey(fileobj, self._fileobj_lookup(fileobj), events, data)
if key.fd in self._fd_to_key:
raise KeyError("{!r} (FD {}) is already registered"
.format(fileobj, key.fd))
z_events = 0
if events & EVENT_READ:
z_events |= POLLIN
if events & EVENT_WRITE:
z_events |= POLLOUT
try:
self._poller.register(key.fd, z_events)
except ZMQError as exc:
raise OSError(exc.errno, exc.strerror) from exc
self._fd_to_key[key.fd] = key
return key
def unregister(self, fileobj):
try:
key = self._fd_to_key.pop(self._fileobj_lookup(fileobj))
except KeyError:
raise KeyError("{!r} is not registered".format(fileobj)) from None
try:
self._poller.unregister(key.fd)
except ZMQError as exc:
self._fd_to_key[key.fd] = key
raise OSError(exc.errno, exc.strerror) from exc
return key
def modify(self, fileobj, events, data=None):
try:
fd = self._fileobj_lookup(fileobj)
key = self._fd_to_key[fd]
except KeyError:
raise KeyError("{!r} is not registered".format(fileobj)) from None
if data == key.data and events == key.events:
return key
if events != key.events:
z_events = 0
if events & EVENT_READ:
z_events |= POLLIN
if events & EVENT_WRITE:
z_events |= POLLOUT
try:
self._poller.modify(fd, z_events)
except ZMQError as exc:
raise OSError(exc.errno, exc.strerror) from exc
key = key._replace(data=data, events=events)
self._fd_to_key[key.fd] = key
return key
def close(self):
self._fd_to_key.clear()
self._poller = None
def get_map(self):
return self._map
def _key_from_fd(self, fd):
"""Return the key associated to a given file descriptor.
Parameters:
fd -- file descriptor
Returns:
corresponding key, or None if not found
"""
try:
return self._fd_to_key[fd]
except KeyError:
return None
def select(self, timeout=None):
if timeout is None:
timeout = None
elif timeout <= 0:
timeout = 0
else:
# poll() has a resolution of 1 millisecond, round away from
# zero to wait *at least* timeout seconds.
timeout = math.ceil(timeout * 1e3)
ready = []
try:
z_events = self._poller.poll(timeout)
except ZMQError as exc:
if exc.errno == EINTR:
return ready
else:
raise OSError(exc.errno, exc.strerror) from exc
for fd, evt in z_events:
events = 0
if evt & POLLIN:
events |= EVENT_READ
if evt & POLLOUT:
events |= EVENT_WRITE
if evt & POLLERR:
events = EVENT_READ | EVENT_WRITE
key = self._key_from_fd(fd)
if key:
ready.append((key, events & key.events))
return ready
class ZmqSelector(BaseSelector):
"""A selector that can be used with asyncio's selector base event loops."""
def __init__(self):
# this maps file descriptors to keys
self._fd_to_key = {}
# read-only mapping returned by get_map()
self._map = _SelectorMapping(self)
self._poller = ZMQPoller()
def _fileobj_lookup(self, fileobj):
"""Return a file descriptor from a file object.
This wraps _fileobj_to_fd() to do an exhaustive search in case
the object is invalid but we still have it in our map. This
is used by unregister() so we can unregister an object that
was previously registered even if it is closed. It is also
used by _SelectorMapping.
"""
try:
return _fileobj_to_fd(fileobj)
except ValueError:
# Do an exhaustive search.
for key in self._fd_to_key.values():
if key.fileobj is fileobj:
return key.fd
# Raise ValueError after all.
raise
def register(self, fileobj, events, data=None):
if (not events) or (events & ~(EVENT_READ | EVENT_WRITE)):
raise ValueError("Invalid events: {!r}".format(events))
key = SelectorKey(fileobj, self._fileobj_lookup(fileobj), events, data)
if key.fd in self._fd_to_key:
raise KeyError("{!r} (FD {}) is already registered".format(
fileobj, key.fd))
z_events = 0
if events & EVENT_READ:
z_events |= POLLIN
if events & EVENT_WRITE:
z_events |= POLLOUT
try:
self._poller.register(key.fd, z_events)
except ZMQError as exc:
raise OSError(exc.errno, exc.strerror) from exc
self._fd_to_key[key.fd] = key
return key
def unregister(self, fileobj):
try:
key = self._fd_to_key.pop(self._fileobj_lookup(fileobj))
except KeyError:
raise KeyError("{!r} is not registered".format(fileobj)) from None
try:
self._poller.unregister(key.fd)
except ZMQError as exc:
self._fd_to_key[key.fd] = key
raise OSError(exc.errno, exc.strerror) from exc
return key
def modify(self, fileobj, events, data=None):
try:
fd = self._fileobj_lookup(fileobj)
key = self._fd_to_key[fd]
except KeyError:
raise KeyError("{!r} is not registered".format(fileobj)) from None
if data == key.data and events == key.events:
return key
if events != key.events:
z_events = 0
if events & EVENT_READ:
z_events |= POLLIN
if events & EVENT_WRITE:
z_events |= POLLOUT
try:
self._poller.modify(fd, z_events)
except ZMQError as exc:
raise OSError(exc.errno, exc.strerror) from exc
key = key._replace(data=data, events=events)
self._fd_to_key[key.fd] = key
return key
def close(self):
self._fd_to_key.clear()
self._poller = None
def get_map(self):
return self._map
def _key_from_fd(self, fd):
"""Return the key associated to a given file descriptor.
Parameters:
fd -- file descriptor
Returns:
corresponding key, or None if not found
"""
try:
return self._fd_to_key[fd]
except KeyError:
return None
def select(self, timeout=None):
if timeout is None:
timeout = None
elif timeout <= 0:
timeout = 0
else:
# poll() has a resolution of 1 millisecond, round away from
# zero to wait *at least* timeout seconds.
timeout = math.ceil(timeout * 1e3)
ready = []
try:
z_events = self._poller.poll(timeout)
except ZMQError as exc:
if exc.errno == EINTR:
return ready
else:
raise OSError(exc.errno, exc.strerror) from exc
for fd, evt in z_events:
events = 0
if evt & POLLIN:
events |= EVENT_READ
if evt & POLLOUT:
events |= EVENT_WRITE
if evt & POLLERR:
events = EVENT_READ | EVENT_WRITE
key = self._key_from_fd(fd)
if key:
ready.append((key, events & key.events))
return ready