def call(self, rpc, msg, timeout):
""" Save the object that has been created and return the response.
Will timeout after timeout ms if response has not been received
Accepted Arguments:
timeout -- (Integer) ms to wait for a response before returning
"""
# Define local callback function to handle RPC response
# and initialize result dict
result = {
"done": False,
"success": False,
"response": None,
"error_msg": "timeout",
"error_code": None
}
#Can't use just a simple boolean for 'done' because of the way it is
#referenced in the callback. The scope isn't clear and python
#will redefine 'done' rather than change the value unless explicitly
#defined as 'global done'
#done = False
def callback(request, response):
result["response"] = response
result["done"] = True
result["error_msg"] = ""
result["success"] = True
#Setup the RPC channel
channel = SocketRpcChannel(host=self.host, port=self.port)
controller = channel.newController()
service = self.service_stub_class(channel)
#Make the RPC call and pass in a generic object with a
#function called "run" linked to callback
try:
#Attempting to do something similar to a JAVA anonymous class
#Create an instalce of a new generic type initialized with a
#dict that has a run method pointing to the callback function
rpc(service, controller, msg, type("", (), {"run": callback})())
except Exception, info:
print controller.error
class TestRpcThread(unittest.TestCase):
''' Unit tests for the protobuf.service.RpcThread class.'''
def setUp(self):
self.channel = SocketRpcChannel(host=host, port=port)
self.controller = self.channel.newController()
self.service = test_pb2.TestService_Stub(self.channel)
self.request = test_pb2.Request()
self.request.str_data = 'I like cheese'
self.callback = lambda request, response : response
self.thread = service.RpcThread(test_pb2.TestService_Stub.TestMethod,
self.service,
self.controller,
self.request,
self.callback)
ServerThread.start_server()
def tearDown(self):
pass
def test__init__(self):
'''Test RpcThread constructor.'''
self.assertEqual(self.thread.method,
test_pb2.TestService_Stub.TestMethod,
"Attribute 'method' incorrectly initialized")
self.assertEqual(self.thread.service,
self.service,
"Attribute 'service' incorrectly initialized")
self.assertEqual(self.thread.controller,
self.controller,
"Attribute 'controller' incorrectly initialized")
self.assertEqual(self.thread.request,
self.request,
"Attribute 'request' incorrectly initialized")
self.assertEqual(self.thread.callback,
self.callback,
"Attribute 'callback' incorrectly initialized")
self.assertEqual(self.thread.isDaemon(), True,
"Thread not set as Daemon")
def test_run(self):
'''Test the run method'''
try:
self.thread.run()
except Exception, e:
self.assert_(False, "TestRpcThread.run() threw and exception", e)
def setUp(self):
self.channel = SocketRpcChannel(host=host, port=port)
self.controller = self.channel.newController()
self.service = test_pb2.TestService_Stub(self.channel)
self.request = test_pb2.Request()
self.request.str_data = 'I like cheese'
self.callback = lambda request, response : response
self.thread = service.RpcThread(test_pb2.TestService_Stub.TestMethod,
self.service,
self.controller,
self.request,
self.callback)
ServerThread.start_server()
def call(self, rpc, msg, timeout):
""" Save the object that has been created and return the response.
Will timeout after timeout ms if response has not been received
Accepted Arguments:
timeout -- (Integer) ms to wait for a response before returning
"""
# Define local callback function to handle RPC response
# and initialize result dict
result = {"done":False, "success":False, "response":None,
"error_msg":"timeout", "error_code":None}
#Can't use just a simple boolean for 'done' because of the way it is
#referenced in the callback. The scope isn't clear and python
#will redefine 'done' rather than change the value unless explicitly
#defined as 'global done'
#done = False
def callback(request, response):
result["response"] = response
result["done"] = True
result["error_msg"] = ""
result["success"] = True
#Setup the RPC channel
channel = SocketRpcChannel(host=self.host, port=self.port)
controller = channel.newController()
service = self.service_stub_class(channel)
#Make the RPC call and pass in a generic object with a
#function called "run" linked to callback
try:
#Attempting to do something similar to a JAVA anonymous class
#Create an instalce of a new generic type initialized with a
#dict that has a run method pointing to the callback function
rpc(service, controller, msg, type("", (), {"run":callback})())
except Exception, info:
print controller.error
def __init__(self, service_stub_class, port, host):
''' Contruct a new ProtoBufRpcRequest and return it.
Accepted Arguments:
service_stub_class -- (Service_Stub) The client side RPC
stub class produced by protoc from
the .proto file
port -- (Integer) The port on which the service is running
on the RPC server.
host -- (String) The hostname or IP address of the server
running the RPC service.
'''
self.service_stub_class = service_stub_class
self.port = port
self.host = host
# Setup the RPC channel
self.channel = SocketRpcChannel(host=self.host, port=self.port)
self.service = self.service_stub_class(self.channel)
# go through service_stub methods and add a wrapper function to
# this object that will call the method
for method in service_stub_class.GetDescriptor().methods:
# Add service methods to the this object
rpc = lambda request, timeout=None, callback=None, service=self, method=method.name : service.call(
service_stub_class.__dict__[method], request, timeout, callback)
rpc.__doc__ = method.name + ' method of the ' + \
service_stub_class.DESCRIPTOR.name + ' from the ' + \
service_stub_class.__module__ + ' module generated by the ' + \
'protoc compiler. This method can be called synchronously ' + \
'by setting timeout -> ms or asynchrounously by setting ' + \
'callback -> function(request,response)\n\n' + \
'Synchronous Example:\n' + \
'\trequest = ' + method.input_type.name + '()\n' + \
'\ttry:\n' + \
'\t#Wait 1000ms for a response\n' + \
'\t\tresponse = ' + method.name + '(request, timeout=1000)\n' + \
'\texcept: RpcException\n' + \
'\t\t#Handle exception\n\n' + \
'Asynchronous Example:\n' + \
'\tdef callback(request,response):\n' + \
'\t\t#Do some stuff\n' + \
'\trequest = ' + method.input_type.name + '()\n' + \
'\ttry:\n' + \
'\t\t' + method.name + '(request, callback=callback)\n' + \
'\texcept: RpcException\n' + \
'\t\t#Handle exception\n\n'
self.__dict__[method.name] = rpc
class RpcService(object):
''' Class abstracting the Protocol Buffer RPC calls for a supplied
service stub.
'''
def __init__(self, service_stub_class, port, host):
''' Contruct a new ProtoBufRpcRequest and return it.
Accepted Arguments:
service_stub_class -- (Service_Stub) The client side RPC
stub class produced by protoc from
the .proto file
port -- (Integer) The port on which the service is running
on the RPC server.
host -- (String) The hostname or IP address of the server
running the RPC service.
'''
self.service_stub_class = service_stub_class
self.port = port
self.host = host
# Setup the RPC channel
self.channel = SocketRpcChannel(host=self.host, port=self.port)
self.service = self.service_stub_class(self.channel)
# go through service_stub methods and add a wrapper function to
# this object that will call the method
for method in service_stub_class.GetDescriptor().methods:
# Add service methods to the this object
rpc = lambda request, timeout=None, callback=None, service=self, method=method.name : service.call(
service_stub_class.__dict__[method], request, timeout, callback)
rpc.__doc__ = method.name + ' method of the ' + \
service_stub_class.DESCRIPTOR.name + ' from the ' + \
service_stub_class.__module__ + ' module generated by the ' + \
'protoc compiler. This method can be called synchronously ' + \
'by setting timeout -> ms or asynchrounously by setting ' + \
'callback -> function(request,response)\n\n' + \
'Synchronous Example:\n' + \
'\trequest = ' + method.input_type.name + '()\n' + \
'\ttry:\n' + \
'\t#Wait 1000ms for a response\n' + \
'\t\tresponse = ' + method.name + '(request, timeout=1000)\n' + \
'\texcept: RpcException\n' + \
'\t\t#Handle exception\n\n' + \
'Asynchronous Example:\n' + \
'\tdef callback(request,response):\n' + \
'\t\t#Do some stuff\n' + \
'\trequest = ' + method.input_type.name + '()\n' + \
'\ttry:\n' + \
'\t\t' + method.name + '(request, callback=callback)\n' + \
'\texcept: RpcException\n' + \
'\t\t#Handle exception\n\n'
self.__dict__[method.name] = rpc
def call(self, rpc, request, timeout=None, callback=None):
''' Save the object that has been created and return the response.
Will timeout after timeout ms if response has not been received.
The timeout arg is only used for asynch requests.
If a callback has been supplied the timeout arg is not used.
The response value will be returned for a synch request but nothing
will be returned for an asynch request.
Accepted Arguments:
timeout -- (Integer) ms to wait for a response before returning
'''
# Define local callback function to handle RPC response
# and initialize result dict
result = {'done': False, 'response': None}
def synch_callback(request, response):
result['response'] = response
result['done'] = True
result['error_msg'] = ''
result['success'] = True
# If no callback has been passed in then this is meant to be synchronous
if callback == None:
rpc_callback = synch_callback
else:
if ((not callable(callback) and
(callback.__class__.__dict__.get('run') == None or
callback.run.func_code.co_argcount < 2)) or
(callable(callback) and callback.func_code.co_argcount < 2)):
raise Exception("callback must be a callable with signature " +
"callback(request, response, ...) or an " +
"object with a callable run function with " +
"the same signature")
rpc_callback = callback
# Create a controller for this call
controller = self.channel.newController()
# Spawn a new thread to wait for the callback so this can return
# immediately if an asynch callback has been requested
rpc_thread = RpcThread(rpc, self.service, controller,
request, rpc_callback)
rpc_thread.start()
# If a callback has been passed in return
if rpc_callback == callback:
return
else:
if timeout == None:
timeout = 100
end = time() + (timeout / 1000)
# Tight loop waiting for timeout or synch_callback to set done to True
while time() < end and not result['done']:
if controller.failed():
if type(controller.error) is str:
raise Exception(controller.error)
else:
raise controller.error
if time() >= end and not result['done']:
raise RpcError('request timed out')
return result['response']
