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Freebase数据库搭建及Python调用

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本地Freebase数据库搭建及Python查询调用

Requirements

  • OpenLink Virtuoso 7.2.11
  • Python (SPARQLWrapper, urllib)

Setup

Freebase data dump

提供网盘数据下载

https://pan.baidu.com/s/1poRzNg2xSYTF1DQEfvmEDg 提取码: aeak

OpenLink Virtuoso

可以通过下面的链接下载免安装版的，也可在在链接进行源码安装

https://github.com/openlink/virtuoso-opensource/releases/tag/v7.2.11

Managing the Virtuoso service

脚本链接:https://github.com/dki-lab/Freebase-Setup 可先参考本文Questions章节修改脚本

提供了一个用于管理Virtuoso服务的包装器脚本（ virtuoso.py ）。要使用它，首先将脚本中的 virtuosoPath 更改为本地Virtuoso目录。假设Virtuoso db文件位于与脚本 virtuoso.py 相同的目录下名为 virtuoso_db 的目录中，并且3001是服务的预期HTTP端口，要启动Virtuoso服务：

python virtuoso.py start 3001 -d virtuoso_db

停止同一端口上当前正在运行的服务：

python virtuoso.py stop 3001

建议使用至少具有100 GB RAM的服务器。您可以通过提供的脚本调整服务可能使用的最大RAM量和其他配置。

运行成功之后界面输出如下

Freebase数据库搭建及Python调用

在浏览器界面输入localhost:3001 出现以下界面表示运行成功

Freebase数据库搭建及Python调用

Python调用数据库

安装python库

pip install SPARQLWrapper pip install urllib

可通过python对本地数据库进行查询调用

#!/usr/bin/env python  
# -*- coding: utf-8 -*-  
# @File : freebase.py  
# @Author : AZ  
# @Time : 2023/9/12 下午9:11  
  
from SPARQLWrapper import SPARQLWrapper, JSON  
from urllib.parse import urlparse  
  
sparql = SPARQLWrapper('http://localhost:3001/sparql')  

'''  
查询实体对应的 [名称]  
'''  
# entity = "m.01tm_5"  
# sparql_query = "PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>"\  
# "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>"\  
# "PREFIX : <http://rdf.freebase.com/ns/>"\  
# "SELECT DISTINCT ?name where {" \  
# f"VALUES ?x0 {{:{entity}}} " \  
# "?x0 :type.object.name ?name " \  
# "FILTER(LANGMATCHES(LANG(?name), 'en'))." \  
# "}"  
  
'''  
查询头实体对应的 [关系,尾节点MID,尾节点名称]  
'''  
# entity = "m.07tczt"  
# sparql_query = "PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> " \  
# "PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> " \  
# "PREFIX : <http://rdf.freebase.com/ns/> " \  
# "SELECT DISTINCT ?ns ?x0 ?name WHERE { " \  
# f"VALUES ?x3 {{:{entity}}} " \  
# "?x0 ?ns ?x3 . " \  
# "?x0 :type.object.name ?name " \  
# "FILTER ( ?x0 != ?x3 )" \  
# "FILTER(LANGMATCHES(LANG(?name), 'en'))." \  
# "}"  
  
'''  
查询关系对应的 [头节点MID,头节点名称，尾节点MID，尾节点名称]  
'''  
relation = 'spaceflight.rocket_engine_manufacturer.rocket_engines'  
# entity = 'm.0dl93'  
# f"VALUES ?x0 {{:{entity}}} " \  
sparql_query = "PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> " \  
"PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> " \  
"PREFIX : <http://rdf.freebase.com/ns/> " \  
"SELECT DISTINCT ?x0 ?name0 ?x1 ?name1 WHERE { " \  
f"?x0 :{relation} ?x1." \  
"FILTER ( ?x0 != ?x1 )" \  
"?x1 :type.object.name ?name1 " \  
"FILTER(LANGMATCHES(LANG(?name1), 'en'))" \  
"?x0 :type.object.name ?name0 " \  
"FILTER(LANGMATCHES(LANG(?name0), 'en'))" \  
"}"  
  
sparql.setQuery(sparql_query)  
sparql.setReturnFormat(JSON)  
# results = sparql.query().convert() # json,type为dict  
# print(results['results']['bindings'])  
  
try:  
    ret = sparql.queryAndConvert()  
    # print(ret)  
    for res in ret["results"]["bindings"]:  
    ans = [urlparse(res[k]['value']).path for k in res]  
    print(f"{ans}")  
 
    # AnswerArgument = urlparse(r['value']['value']).path  
    # AnswerArgument = AnswerArgument.split('/')[2]  
    # print(AnswerArgument)  
  
except Exception as e:  
    print(e)

输出结果

['/ns/m.03fkyw', 'SpaceX', '/ns/m.03g0k4', 'Merlin']
['/ns/m.03fkyw', 'SpaceX', '/ns/m.03g0sk', 'Kestrel']
['/ns/m.01vhl6', 'Rocketdyne', '/ns/m.032blg', 'Space Shuttle main engine']
['/ns/m.01vhl6', 'Rocketdyne', '/ns/m.034_44', 'Rocketdyne F-1']
['/ns/m.01vhl6', 'Rocketdyne', '/ns/m.043jfp', 'RS-68']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlty_', 'RD-250']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltwn', 'RD-250PM']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.07dk1d', 'RD-180']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlt61', 'RD-550']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlt6v', 'RD-512']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlt7j', 'RD-511']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlt87', 'RD-510']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlt9t', 'RD-502']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvw0', 'RD-161P']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltxc', 'RD-250M']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwf0', 'RD-117']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvp4', 'RD-2']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvqg', 'RD-1']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltjy', 'RD-270']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02wts37', 'RD-107']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwpz', 'RD-108']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwqt', 'RD-107A']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvdf', 'RD-215U']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.07ffmj', 'RD-170']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlty5', 'RD-250P']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlv5y', 'RD-218U']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltbl', 'RD-350']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltc9', 'RD-303']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltd2', 'RD-302']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltdw', 'RD-301']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlv54', 'RD-219']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvgs', 'RD-214U']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvpt', 'RD-1KhZ']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlth7', 'RD-274']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltgf', 'RD-275']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvb0', 'RD-216U']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlw89', 'RD-123']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwlp', 'RD-110']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlv95', 'RD-216M']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwcf', 'RD-119']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlt_j', 'RD-224D']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltj2', 'RD-273']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltks', 'RD-268']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltlm', 'RD-264']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltmg', 'RD-263']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltn9', 'RD-262']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltp2', 'RD-261']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltpy', 'RD-254']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltqp', 'RD-253F']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltrh', 'RD-253']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltsb', 'RD-252']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltt3', 'RD-251M']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltvt', 'RD-251']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltzt', 'RD-225']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlv09', 'RD-224']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlv14', 'RD-223']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlv1y', 'RD-222']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlv2t', 'RD-221']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlv3k', 'RD-220']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlv4c', 'RD-219U']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlv6s', 'RD-218']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlv7m', 'RD-217U']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvbw', 'RD-216']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvcq', 'RD-215M']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvf4', 'RD-215']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwgn', 'RD-115']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwhf', 'RD-114']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwj8', 'RD-113']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwk0', 'RD-112']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwmh', 'RD-109']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlttz', 'RD-251P']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvnk', 'RD-3']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlw1q', 'RD-134']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvsj', 'RD-172']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvv5', 'RD-171']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvwq', 'RD-161']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlw9x', 'RD-120K']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlt8_', 'RD-503']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xltfn', 'RD-280']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlv_b', 'RD-141']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvfy', 'RD-214F']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvhm', 'RD-214']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvjg', 'RD-213 (D-13)']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvk8', 'RD-212 (D-41)']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvl3', 'RD-211']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvlz', 'RD-210']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvms', 'RD-200']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvr3', 'RD-191']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvtc', 'RD-171M']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvxg', 'RD-150']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvy6', 'RD-146']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvyz', 'RD-143']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlvzl', 'RD-142']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlw03', 'RD-136']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlw0x', 'RD-135']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlw2g', 'RD-133']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlw36', 'RD-130']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlw3z', 'RD-129']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlw4p', 'RD-128']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlw5d', 'RD-127']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlw63', 'RD-126']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlw6v', 'RD-125']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlw7j', 'RD-124']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlw93', 'RD-121']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwd6', 'RD-118']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwft', 'RD-116']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwkv', 'RD-111']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwn8', 'RD-108A']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwp3', 'RD-108MM']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwrn', 'RD-107MM']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlws_', 'RD-106']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwtv', 'RD-105']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwvp', 'RD-103M']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwwh', 'RD-103']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.02xlwxb', 'RD-101']
['/ns/m.02p_3s6', 'NPO Energomash', '/ns/m.03jz69l', 'RD-100']
['/ns/m.05fj01', 'Thiokol', '/ns/m.03nqqz', 'Reaction Motors XLR99']
['/ns/m.0dl93', 'Pratt & Whitney', '/ns/m.07tczt', 'RS-27A']
['/ns/m.0dl93', 'Pratt & Whitney', '/ns/m.0351y6', 'RL10']
['/ns/m.06pwfx', 'Kuznetsov Design Bureau', '/ns/m.0b19_q', 'NK-33']
['/ns/m.080jfm1', 'Reaction Motors', '/ns/m.02nc08', 'Reaction Motors XLR11']
['/ns/m.0511xg', 'Yuzhmash', '/ns/m.02xlwbn', 'RD-120']
['/ns/m.03c_441', 'Chemical Automatics Design Bureau', '/ns/m.07kfw0m', 'RD-0146']

Questions

搭建过程中在网页显示的步骤出现了一些问题，需要对脚本进行修改，主要修改点是增加了页面缓存文件的路径 "ServerRoot = /home/name/Freebase/virtuoso-opensource/vsp\n"

virtuoso.py 脚本修改

# This script provides a convenient wrapper for the Virtuoso SPARQL server.
# Adapted from Sempre (https://github.com/percyliang/sempre)

import os
import sys
import subprocess
import argparse

virtuosoPath = "/usr/local/virtuoso-opensource"
if not os.path.exists(virtuosoPath):
  print(f"{virtuosoPath} does not exist")
  sys.exit(1)

# Virtuoso has two services: the server (isql) and SPARQL endpoint
def isqlPort(port): return 10000 + port
def httpPort(port): return port

def run(command):
  print(f"RUNNING: {command}")
  res = subprocess.run(command, shell=True, stdout=subprocess.PIPE)
  return res.stdout

def start(dbPath, port):

  if not os.path.exists(dbPath):
    os.mkdir(dbPath)

  # Recommended: 70% of RAM, each buffer is 8K
  # Use a fraction of the free RAM. The result may vary across runs.
  # memFree = parseInt(`cat /proc/meminfo | grep MemFree | awk '{print $2}'`) # KB
  # Use a fraction of the total RAM. The result is the same across runs.
  memFree = int(run("cat /proc/meminfo | grep MemTotal | awk '{print $2}'")) # KB
  numberOfBuffers = memFree * 0.15 / 8
  maxDirtyBuffers = numberOfBuffers / 2
  print(f"{memFree} KB free, using {numberOfBuffers} buffers, {maxDirtyBuffers} dirty buffers")

  # Configuration options:
  #   http://docs.openlinksw.com/virtuoso/dbadm.html
  #   http://virtuoso.openlinksw.com/dataspace/doc/dav/wiki/Main/VirtConfigScale
  config = (
    f"[Database]\n"
    f"DatabaseFile = {dbPath}/virtuoso.db\n"
    f"ErrorLogFile = {dbPath}/virtuoso.log\n"
    f"LockFile = {dbPath}/virtuoso.lck\n"
    f"TransactionFile = {dbPath}/virtuoso.trx\n"
    f"xa_persistent_file = {dbPath}/virtuoso.pxa\n"
    f"ErrorLogLevel = 7\n"
    f"FileExtend = 200\n"
    f"MaxCheckpointRemap = 2000\n"
    f"Striping = 0\n"
    f"TempStorage = TempDatabase\n"
    f"\n"
    f"[TempDatabase]\n"
    f"DatabaseFile = {dbPath}/virtuoso-temp.db\n"
    f"TransactionFile = {dbPath}/virtuoso-temp.trx\n"
    f"MaxCheckpointRemap = 2000\n"
    f"Striping = 0\n"
    f"\n"
    f"[Parameters]\n"
    f"ServerPort = {isqlPort(port)}\n"
    f"LiteMode = 0\n"
    f"DisableUnixSocket = 1\n"
    f"DisableTcpSocket = 0\n"
    f"ServerThreads = 100 ; increased from 20\n"
    f"CheckpointInterval = 60\n"
    f"O_DIRECT = 1 ; increased from 0\n"
    f"CaseMode = 2\n"
    f"MaxStaticCursorRows = 100000\n"
    f"CheckpointAuditTrail = 0\n"
    f"AllowOSCalls = 0\n"
    f"SchedulerInterval = 10\n"
    f"DirsAllowed = .\n"
    f"ThreadCleanupInterval = 0\n"
    f"ThreadThreshold = 10\n"
    f"ResourcesCleanupInterval = 0\n"
    f"FreeTextBatchSize = 100000\n"
#    f"SingleCPU = 0\n"
    f"PrefixResultNames = 0\n"
    f"RdfFreeTextRulesSize = 100\n"
    f"IndexTreeMaps = 256\n"
    f"MaxMemPoolSize = 200000000\n"
    f"PrefixResultNames = 0\n"
    f"MacSpotlight = 0\n"
    f"IndexTreeMaps = 64\n"
    f"NumberOfBuffers = {numberOfBuffers}\n"
    f"MaxDirtyBuffers = {maxDirtyBuffers}\n"
    f"\n"
    f"[SPARQL]\n"
    f"ResultSetMaxRows = 50000\n"
    f"MaxQueryCostEstimationTime = 600 ; in seconds (increased)\n"
    f"MaxQueryExecutionTime = 180; in seconds (increased)\n"
    f"\n"
    f"[HTTPServer]\n"
    f"ServerPort = {httpPort(port)}\n"
    f"ServerRoot = /home/name/Freebase/virtuoso-opensource/vsp\n" # 有了这个才可以打开网页版的界面
    f"Charset = UTF-8\n"
    f"ServerThreads = 15 ; increased from unknown\n"
  ) 

  configPath = f"{dbPath}/virtuoso.ini"
  # configPath = f"/home/name/Freebase/virtuoso-opensource/database/virtuoso.ini"
  print(config)
  print()
  print(configPath)
  print(f"==== Starting Virtuoso server for {dbPath} on port {port}...")
  with open(configPath, 'w') as f:
      f.write(config)
  run(f"{virtuosoPath}/bin/virtuoso-t +configfile {configPath} +wait")
  # run(f"virtuoso-t +configfile {configPath} -fd")

def stop(port):
  run(f"echo 'shutdown;' | {virtuosoPath}/bin/isql localhost:{isqlPort(port)}")

def status(port):
  run(f"echo 'status();' | {virtuosoPath}/bin/isql localhost:{isqlPort(port)}")

############################################################
# Main

if __name__ == "__main__":
  parser = argparse.ArgumentParser(description="manage Virtuoso services")
  parser.add_argument("action", type=str, help="start or stop")
  parser.add_argument("port", type=int, help="port for the SPARQL HTTP endpoint")
  parser.add_argument("-d", "--db-path", type=str, help="path to the db directory")

  args = parser.parse_args()
  if args.action == "start":
    if not args.db_path:
      print("please specify path to the db directory with -d")
      sys.exit()
      
    if not os.path.isdir(args.db_path):
      print("the path specified does not exist")
      sys.exit()

    start(args.db_path, args.port)
  elif args.action == "stop":
    stop(args.port)
  else:
    print(f"invalid action: ${args.action}")
    sys.exit()