def _handle_stream(self, connection, address):
"""A routine to handle incoming requests from
a TCP client.
"""
# Receive an introductory message with the message type.
packed_message_type = recvall(connection, 4)
message_type_int = unpack_int(packed_message_type)[0]
packed_message_length = recvall(connection, 4)
message_length = unpack_int(packed_message_length)[0]
try:
message_type = EvaluatorMessageTypes(message_type_int)
except ValueError as e:
trace = traceback.format_exception(None, e, e.__traceback__)
logger.info(f"Bad message type received: {trace}")
# Discard the unrecognised message.
if message_length > 0:
recvall(connection, message_length)
return
if message_type is EvaluatorMessageTypes.Submission:
self._handle_job_submission(connection, address, message_length)
elif message_type is EvaluatorMessageTypes.Query:
self._handle_job_query(connection, message_length)
def _send_query_to_server(self, request_id):
"""Attempts to connect to the calculation server, and
submit the requested calculations.
Parameters
----------
request_id: str
The id of the job to query.
Returns
-------
str, optional:
The status of the submitted job.
Returns None if the calculation has not yet completed.
"""
server_response = None
# Attempt to establish a connection to the server.
connection_settings = (
self._connection_options.server_address,
self._connection_options.server_port,
)
connection = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
connection.connect(connection_settings)
try:
# Encode the request id into the message.
message_type = pack_int(EvaluatorMessageTypes.Query)
encoded_request_id = request_id.encode()
length = pack_int(len(encoded_request_id))
connection.sendall(message_type + length + encoded_request_id)
# Wait for the server response.
header = recvall(connection, 4)
length = unpack_int(header)[0]
# Decode the response from the server. If everything
# went well, this should be the finished calculation.
if length > 0:
encoded_json = recvall(connection, length)
server_response = encoded_json.decode()
finally:
if connection is not None:
connection.close()
response = None
error = None
if server_response is not None:
response, error = json.loads(server_response, cls=TypedJSONDecoder)
return response, error
def _handle_job_query(self, connection, message_length):
"""An asynchronous routine for handling the receiving and
processing of request status queries from a client
Parameters
----------
connection:
An IO stream used to pass messages between the
server and client.
message_length: int
The length of the message being received.
"""
encoded_request_id = recvall(connection, message_length)
client_request_id = encoded_request_id.decode()
response = None
if client_request_id not in self._batch_ids_per_client_id:
error = EvaluatorException(
message=f"The request id ({client_request_id}) was not found "
f"on the server.", )
else:
response, error = self._query_request_status(client_request_id)
response_json = json.dumps((response, error), cls=TypedJSONEncoder)
encoded_response = response_json.encode()
length = pack_int(len(encoded_response))
connection.sendall(length + encoded_response)
def _send_calculations_to_server(self, submission):
"""Attempts to connect to the calculation server, and
submit the requested calculations.
Parameters
----------
submission: _Submission
The jobs to submit.
Returns
-------
str, optional:
The id which the server has assigned the submitted calculations.
This can be used to query the server for when the calculation
has completed.
Returns None if the calculation could not be submitted.
EvaluatorException, optional
Any exceptions raised while attempting the submit the request.
"""
# Attempt to establish a connection to the server.
connection_settings = (
self._connection_options.server_address,
self._connection_options.server_port,
)
connection = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
connection.connect(connection_settings)
request_id = None
try:
# Encode the submission json into an encoded
# packet ready to submit to the server.
message_type = pack_int(EvaluatorMessageTypes.Submission)
encoded_json = submission.json().encode()
length = pack_int(len(encoded_json))
connection.sendall(message_type + length + encoded_json)
# Wait for confirmation that the server has received
# the jobs.
header = recvall(connection, 4)
length = unpack_int(header)[0]
# Decode the response from the server. If everything
# went well, this should be the id of the submitted
# calculations.
encoded_json = recvall(connection, length)
request_id, error = json.loads(encoded_json.decode(),
cls=TypedJSONDecoder)
except Exception as e:
trace = traceback.format_exception(None, e, e.__traceback__)
error = EvaluatorException(message=trace)
finally:
if connection is not None:
connection.close()
# Return the ids of the submitted jobs.
return request_id, error
def _handle_job_submission(self, connection, address, message_length):
"""An asynchronous routine for handling the receiving and processing
of job submissions from a client.
Parameters
----------
connection:
An IO stream used to pass messages between the
server and client.
address: str
The address from which the request came.
message_length: int
The length of the message being received.
"""
logger.info("Received estimation request from {}".format(address))
# Read the incoming request from the server. The first four bytes
# of the response should be the length of the message being sent.
# Decode the client submission json.
encoded_json = recvall(connection, message_length)
json_model = encoded_json.decode()
request_id = None
error = None
try:
# noinspection PyProtectedMember
submission = EvaluatorClient._Submission.parse_json(json_model)
submission.validate()
except Exception as e:
formatted_exception = traceback.format_exception(
None, e, e.__traceback__)
error = EvaluatorException(
message=f"An exception occured when parsing "
f"the submission: {formatted_exception}")
submission = None
if error is None:
while request_id is None or request_id in self._batch_ids_per_client_id:
request_id = str(uuid.uuid4()).replace("-", "")
self._batch_ids_per_client_id[request_id] = []
# Pass the id of the submitted requests back to the client
# as well as any error which may have occurred.
return_packet = json.dumps((request_id, error), cls=TypedJSONEncoder)
encoded_return_packet = return_packet.encode()
length = pack_int(len(encoded_return_packet))
connection.sendall(length + encoded_return_packet)
if error is not None:
# Exit early if there is an error.
return
# Batch the request into more managable chunks.
batches = self._prepare_batches(submission, request_id)
# Launch the batches
for batch in batches:
self._launch_batch(batch)