gRPC file evaluation example

greeter_client.py

# Copyright 2015 gRPC authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""The Python implementation of the GRPC helloworld.Greeter client."""

from __future__ import print_function

import time
import datetime
import grpc

import helloworld_pb2
import helloworld_pb2_grpc


def run():
    # NOTE(gRPC Python Team): .close() is possible on a channel and should be
    # used in circumstances in which the with statement does not fit the needs
    # of the code.
    with grpc.insecure_channel('localhost:50051') as channel:
        stub = helloworld_pb2_grpc.GreeterStub(channel)

        i = 1
        while True:
            start = datetime.datetime.now()
            response = stub.SayHello(helloworld_pb2.HelloRequest(name='/Users/warren/code/exec_sample.py'))
            end = datetime.datetime.now()
            elapsed = (end - start)
            print(response.message, "in", elapsed.microseconds, "microseconds")
            break

if __name__ == '__main__':
    run()

greeter_server.py

# Copyright 2015 gRPC authors.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
"""The Python implementation of the GRPC helloworld.Greeter server."""

from concurrent import futures
import time

import grpc

import helloworld_pb2
import helloworld_pb2_grpc

_ONE_DAY_IN_SECONDS = 60 * 60 * 24

import sys
import io

# setup the environment
backup = sys.stdout

# based on https://stackoverflow.com/questions/5136611/capture-stdout-from-a-script-in-python

class Greeter(helloworld_pb2_grpc.GreeterServicer):

    def SayHello(self, request, context):
        backup = sys.stdout
        sys.stdout = io.StringIO()     # capture output
        exec(open(request.name).read())
        out = sys.stdout.getvalue() # release output
        # ####

        sys.stdout.close()  # close the stream
        sys.stdout = backup # restore original stdout
        return helloworld_pb2.HelloReply(message=out)


def serve():
    server = grpc.server(futures.ThreadPoolExecutor(max_workers=10))
    helloworld_pb2_grpc.add_GreeterServicer_to_server(Greeter(), server)
    server.add_insecure_port('[::]:50051')
    server.start()
    try:
        while True:
            time.sleep(_ONE_DAY_IN_SECONDS)
    except KeyboardInterrupt:
        server.stop(0)


if __name__ == '__main__':
    serve()