class Method(Messenger):
"""
QMF method.
:ivar name: The method name.
:type name: str
:ivar arguments: The method arguments.
:type arguments: dict
:ivar connection: A broker connection.
:type connection: Connection
:ivar session: An AMQP session.
:type session: qpid.messaging.Session.
:ivar sender: A message sender.
:type sender: qpid.messaging.Sender
:ivar receiver: A message sender.
:type receiver: qpid.messaging.Receiver
"""
def __init__(self, url, name, arguments):
"""
:param url: The broker url.
:type url: str
:param name: The method name.
:type name: str
:param arguments: The method arguments.
:type arguments: dict
"""
super(Method, self).__init__(url)
self.name = name
self.arguments = arguments
self.connection = Connection(url)
self.session = None
self.sender = None
self.receiver = None
self.reply_to = REPLY_TO % uuid4()
@property
def content(self):
return {
'_object_id': OBJECT_ID,
'_method_name': self.name,
'_arguments': self.arguments
}
@property
def properties(self):
return {
'qmf.opcode': '_method_request',
'x-amqp-0-10.app-id': 'qmf2',
'method': 'request'
}
def is_open(self):
"""
Get whether the method is open.
:return: True if open.
:rtype: bool
"""
return self.sender is not None
def open(self):
"""
Open a connection and get a sender and receiver.
"""
if self.is_open():
# already open
return
self.connection.open()
self.session = self.connection.session()
self.sender = self.session.sender(ADDRESS)
self.receiver = self.session.receiver(self.reply_to)
def repair(self):
"""
Repair the connection and get a sender and receiver.
"""
self.close()
self.connection.close()
self.connection.open()
self.session = self.connection.session()
self.sender = self.session.sender(ADDRESS)
self.receiver = self.session.receiver(self.reply_to)
def close(self):
"""
Close the sender and receiver.
"""
session = self.session
self.session = None
sender = self.sender
self.sender = None
receiver = self.receiver
self.receiver = None
try:
receiver.close()
except Exception:
pass
try:
sender.close()
except Exception:
pass
try:
session.close()
except Exception:
pass
def on_reply(self, reply):
"""
Process the QMF reply.
:param reply: The reply.
:type reply: Message
:raise: Error on failures.
"""
opcode = reply.properties['qmf.opcode']
if opcode != '_exception':
# succeeded
return
body = reply.content
values = body['_values']
code = values['error_code']
description = values['error_text']
if code == EEXIST:
return
raise Error(description, code)
@reliable
def __call__(self):
"""
Invoke the method.
:raise: Error on failure.
"""
self.open()
try:
request = Message(
content=self.content,
reply_to=self.reply_to,
properties=self.properties,
correlation_id=utf8(uuid4()),
subject=SUBJECT)
self.sender.send(request)
reply = self.receiver.fetch()
self.session.acknowledge()
self.on_reply(reply)
finally:
self.close()
class Sender(BaseSender):
"""
An AMQP message sender.
"""
def __init__(self, url):
"""
:param url: The broker url.
:type url: str
"""
BaseSender.__init__(self, url)
self.connection = Connection(url)
self.session = None
def is_open(self):
"""
Get whether the sender has been opened.
:return: True if open.
:rtype bool
"""
return self.session is not None
@reliable
def open(self):
"""
Open the sender.
"""
if self.is_open():
# already opened
return
self.connection.open()
self.session = self.connection.session()
def repair(self):
"""
Repair the sender.
"""
self.close()
self.connection.close()
self.connection.open()
self.session = self.connection.session()
def close(self):
"""
Close the reader.
"""
session = self.session
self.session = None
try:
session.close()
except Exception:
pass
@reliable
def send(self, address, content, ttl=None):
"""
Send a message.
:param address: An AMQP address.
:type address: str
:param content: The message content
:type content: buf
:param ttl: Time to Live (seconds)
:type ttl: float
"""
sender = self.session.sender(address)
try:
message = Message(content=content, durable=self.durable, ttl=ttl)
sender.send(message)
log.debug('sent (%s)', address)
finally:
sender.close()
def test_session(self):
url = TEST_URL
c = Connection(url)
c._impl = Mock()
session = c.session()
self.assertEqual(session, c._impl.session.return_value)
def test_session(self):
url = TEST_URL
c = Connection(url)
c._impl = Mock()
session = c.session()
self.assertEqual(session, c._impl.session.return_value)
class Reader(BaseReader):
"""
An AMQP message reader.
:ivar receiver: An AMQP receiver to read.
:type receiver: qpid.messaging.Receiver
"""
def __init__(self, node, url):
"""
:param node: The AMQP node to read.
:type node: gofer.messaging.adapter.model.Node
:param url: The broker url.
:type url: str
:see: gofer.messaging.adapter.url.URL
"""
BaseReader.__init__(self, node, url)
self.connection = Connection(url)
self.session = None
self.receiver = None
def is_open(self):
"""
Get whether the messenger has been opened.
:return: True if open.
:rtype bool
"""
return self.receiver is not None
@reliable
def open(self):
"""
Open the reader.
:raise: NotFound
"""
if self.is_open():
# already open
return
self.connection.open()
self.session = self.connection.session()
self.receiver = self.session.receiver(self.node.address)
def repair(self):
"""
Repair the reader.
:raise: NotFound
"""
self.close()
self.connection.close()
self.connection.open()
self.session = self.connection.session()
self.receiver = self.session.receiver(self.node.address)
def close(self):
"""
Close the reader.
"""
receiver = self.receiver
self.receiver = None
session = self.session
self.session = None
try:
receiver.close()
except Exception:
pass
try:
session.close()
except Exception:
pass
@reliable
def get(self, timeout=None):
"""
Get the next message from the queue.
:param timeout: The read timeout in seconds.
:type timeout: int
:return: The next message or None.
:rtype: Message
"""
try:
impl = self.receiver.fetch(timeout or NO_DELAY)
return Message(self, impl, impl.content)
except Empty:
pass
@reliable
def ack(self, message):
"""
Acknowledge all messages received on the session.
:param message: The message to acknowledge.
:type message: qpid.messaging.Message
"""
self.session.acknowledge(message=message)
@reliable
def reject(self, message, requeue=True):
"""
Reject the specified message.
:param message: The message to reject.
:type message: qpid.messaging.Message
:param requeue: Requeue the message or discard it.
:type requeue: bool
"""
if requeue:
disposition = Disposition(RELEASED)
else:
disposition = Disposition(REJECTED)
self.session.acknowledge(message=message, disposition=disposition)
class Sender(BaseSender):
"""
An AMQP message sender.
"""
def __init__(self, url):
"""
:param url: The broker url.
:type url: str
"""
BaseSender.__init__(self, url)
self.connection = Connection(url)
self.session = None
def is_open(self):
"""
Get whether the sender has been opened.
:return: True if open.
:rtype bool
"""
return self.session is not None
@reliable
def open(self):
"""
Open the sender.
"""
if self.is_open():
# already opened
return
self.connection.open()
self.session = self.connection.session()
def repair(self):
"""
Repair the sender.
"""
self.close()
self.connection.close()
self.connection.open()
self.session = self.connection.session()
def close(self):
"""
Close the reader.
"""
session = self.session
self.session = None
try:
session.close()
except Exception:
pass
@reliable
def send(self, address, content, ttl=None):
"""
Send a message.
:param address: An AMQP address.
:type address: str
:param content: The message content
:type content: buf
:param ttl: Time to Live (seconds)
:type ttl: float
"""
sender = self.session.sender(address)
try:
message = Message(content=content, durable=self.durable, ttl=ttl)
sender.send(message)
log.debug('sent (%s)', address)
finally:
sender.close()
