web_service.py

# Copyright (c) 2020 PaddlePaddle Authors. All Rights Reserved.
#
# 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.
#!flask/bin/python
# pylint: disable=doc-string-missing

from flask import Flask, request, abort
from multiprocessing import Pool, Process
from paddle_serving_server import OpMaker, OpSeqMaker, Server
from paddle_serving_client import Client


class WebService(object):
    def __init__(self, name="default_service"):
        self.name = name

    def load_model_config(self, model_config):
        self.model_config = model_config

    def _launch_rpc_service(self):
        op_maker = OpMaker()
        read_op = op_maker.create('general_reader')
        general_infer_op = op_maker.create('general_infer')
        general_response_op = op_maker.create('general_response')
        op_seq_maker = OpSeqMaker()
        op_seq_maker.add_op(read_op)
        op_seq_maker.add_op(general_infer_op)
        op_seq_maker.add_op(general_response_op)
        server = Server()
        server.set_op_sequence(op_seq_maker.get_op_sequence())
        server.set_num_threads(16)
        server.load_model_config(self.model_config)
        server.prepare_server(
            workdir=self.workdir, port=self.port + 1, device=self.device)
        server.run_server()

    def prepare_server(self, workdir="", port=9393, device="cpu"):
        self.workdir = workdir
        self.port = port
        self.device = device

    def _launch_web_service(self):
        self.client_service = Client()
        self.client_service.load_client_config(
            "{}/serving_server_conf.prototxt".format(self.model_config))
        self.client_service.connect(["0.0.0.0:{}".format(self.port + 1)])

    def get_prediction(self, request):
        if not request.json:
            abort(400)
        if "fetch" not in request.json:
            abort(400)
        try:
            feed, fetch = self.preprocess(request.json["feed"],
                                          request.json["fetch"])
            if isinstance(feed, dict) and "fetch" in feed:
                del feed["fetch"]
            fetch_map = self.client_service.predict(feed=feed, fetch=fetch)
            for key in fetch_map:
                fetch_map[key] = fetch_map[key].tolist()
            result = self.postprocess(
                feed=feed, fetch=fetch, fetch_map=fetch_map)
            result = {"result": result}
        except ValueError:
            result = {"result": "Request Value Error"}
        return result

    def run_server(self):
        import socket
        localIP = socket.gethostbyname(socket.gethostname())
        print("web service address:")
        print("http://{}:{}/{}/prediction".format(localIP, self.port,
                                                  self.name))
        p_rpc = Process(target=self._launch_rpc_service)
        p_rpc.start()

    def preprocess(self, feed=[], fetch=[]):
        return feed, fetch

    def postprocess(self, feed=[], fetch=[], fetch_map=None):
        return fetch_map