Simple Bloom Filter api with Tornado.

gistfile1.py

import os
import hashlib
import tornado.ioloop
import tornado.web
from tornado import gen

class bv(object):
    def __init__(self):
        self.bit_vector = None

    def make_vector(self,n):
        self.bit_vector = [False]*int(n)

    def add_string(self,str,k):
        n = len(self.bit_vector)
        for i in xrange(0,k):
            hash = hashlib.md5(str).hexdigest()
            self.bit_vector[int(hash,16)%n] = True
            str = hash

    def test_string(self,string,k):
        for i in xrange(0,k):
            hash = hashlib.md5(string).hexdigest()
            if not self.bit_vector[int(hash,16)%len(self.bit_vector)]:
                return False
            str = hash
        return True


class AddHandler(tornado.web.RequestHandler):
    @tornado.gen.coroutine
    def get(self):
        string = self.get_argument('string') if 'string' in self.request.arguments else None
        hash_times = int(self.get_argument('repeat')) if 'repeat' in self.request.arguments else 3
        if string:
            if bv.bit_vector:
                bv.add_string(string,hash_times)
                self.write("string is added")
            else:
                self.write("first set the bit vector using /set_vector/")
        else:
            self.write("Please provide a string")


class ResetHandler(tornado.web.RequestHandler):
    @tornado.gen.coroutine
    def get(self):
        size = self.get_argument('size') if 'size' in self.request.arguments else None
        if size:
            bv.make_vector(size)
            self.write("vector is reset")
        else:
            self.write("Please provide a size for the vector")


class InfoHandler(tornado.web.RequestHandler):
    @tornado.gen.coroutine
    def get(self):
        self.write("use /set_vector/ to initialize bit vector; /add_string/ to add string and /test_string/ to test for it.")


class TestHandler(tornado.web.RequestHandler):
    @tornado.gen.coroutine
    def get(self):
        string = self.get_argument('string') if 'string' in self.request.arguments else None
        hash_times = int(self.get_argument('repeat')) if 'repeat' in self.request.arguments else 3
        if string:
            resp = bv.test_string(string,hash_times)
            if resp:
                self.write("string is present")
            else:
                self.write("string is NOT present")
        else:
            self.write("Please provide a string to test")


def make_app(bv):
    app = tornado.web.Application([
                                   (r"/",InfoHandler),
                                   (r"/add_string/",AddHandler),
                                   (r"/set_vector/",ResetHandler),
                                   (r"/test_string/",TestHandler)
                                   ],bv)
    return app

if __name__=="__main__":
    bv = bv()
    app = make_app(bv)
    app.listen(int(os.environ.get("PORT", 5000)))
    tornado.ioloop.IOLoop.current().start()