EndpointService.py

#!/usr/bin/env python

from flask import Flask, request
from flask.json import jsonify
import sys
import os
import json
import getopt
from time import time
from multiprocessing import Process, Queue, active_children

from mulder.molecule.MTManager import ConfigFile
from mulder.mediator.decomposition.MediatorDecomposer import MediatorDecomposer
from mulder.mediator.planner.MediatorPlanner import MediatorPlanner
from mulder.mediator.planner.MediatorPlanner import contactSource as clm
__author__ = 'kemele'

app = Flask(__name__)
configuration = None
tempType = "MULDER"
configfile = 'config/config.json'

@app.route("/sparql", methods=['POST', 'GET'])
def sparql():
    if request.method == 'GET':
        try:
            query = request.args.get("query", '')
            # query = query.replace('\n', ' ').replace('\r', ' ')
            print('query:', query)
            configuration = ConfigFile(configfile)
            start = time()
            dc = MediatorDecomposer(query, configuration, tempType)
            quers = dc.decompose()
            print ("Mediator Decomposer: \n", quers)
            if quers is None:
                print ("Query decomposer returns None")
                return jsonify({"result": []})

            res = []
            planner = MediatorPlanner(quers, True, clm, None, configuration)
            plan = planner.createPlan()
            print ("Mediator Planner: \n", plan)
            output = Queue()

            plan.execute(output)
            i = 0
            first = 0
            vars = []
            while True:
                r = output.get()
                if i == 0:
                    first = time() - start
                if r == "EOF":
                    print ("END of results ....")
                    break

                vars = r.keys()
                #print (r)
                res.append(r)
                i += 1

            total = time() - start
            return jsonify({"vars": vars, "result": res, "execTime": total, "firstResult": first, "totalRows": i})
        except Exception as e:
            print ("Exception: ", e)
            print ({"result": [], "error": e})
            return jsonify({"result": [], "error": e})
    else:
        return jsonify({"result": [], "error": "Invalid HTTP method used. Use GET "})


def usage():
    usage_str = ("Usage: {program} -c <path_to_config>  "
                 + "\n where \n<path_to_config> "
                 + " is configuration file for Ontario "
                 + "\n")

    print (usage_str.format(program=sys.argv[0]),)


def get_options(argv):
    try:
        opts, args = getopt.getopt(argv, "h:c:")
    except getopt.GetoptError:
        usage()
        sys.exit(1)

    configfile = None
    for opt, arg in opts:
        if opt == "-h":
            usage()
            sys.exit()
        elif opt == "-c":
            configfile = arg
    if not configfile:
        usage()
        sys.exit(1)

    return configfile


if __name__ == "__main__":

    mapping = ""
    tempType = "MULDER"
    argv = sys.argv

    configfile = get_options(argv[1:])
    conf = ConfigFile(configfile)
    port = 5000
    # config = json.load(open(configfile))
    configuration = conf
    app.run(port=port, host="0.0.0.0")