ping多个ip并写入JSON文件python

Question

我正在ping局域网中的多个ip，以检查其是否存在。 该代码将根据计划每分钟运行一次。对于ping多个IP，我使用了多重处理。 借助多处理，可以很好地完成此工作。 同时，我想在ping后将ping结果写入json文件。 但是当写入JSON文件时，它仅写入最后一个ip的输出。我想要所有这三个。 有什么办法做到这一点

这是示例代码：

import json
from multiprocessing import Pool
import subprocess
from datetime import datetime
timestamp = datetime.now().strftime("%B %d %Y, %H:%M:%S")
hosts =  ["192.168.1.47","192.168.1.42"]
count = 1
wait_sec = 1
n = len(hosts)
def main(hosts):
    p = Pool(processes= n)
    result = p.map(beat, hosts)
def beat(hosts):
    #Name for the log file
    name = 'icmp.json'
    ip4write(hosts, name)
def ip4write(hosts, name):
    global ip4a
    ip4a = hosts
    ipve4(hosts, name)
    write(hosts, name)
def ipve4(hosts, name):
    global u
    status, result = subprocess.getstatusoutput("ping -c1 -w2 " + str(ip4a))
    if status == 0:
        print(str(ip4a) + " UP")
        u = " UP"
def write(hosts, name):
    text_file = open(name, "a+")
    with open(name) as json_file:
      try:
          data = json.load(json_file)
      except:
          data = {}
      with open(name, 'w') as outfile:
        data[timestamp] = {
          'monitor.ip':str(hosts),
          'monitor.status': u
        }
        print(data)
        json.dump(data, outfile)
        print('Data written')
    text_file.close()
main(hosts)

JSON文件中的输出：

{"February 15 2019, 16:38:12": {"monitor.status": " UP", "monitor.ip": "192.168.1.42"}}

我所需的输出：

{"February 15 2019, 16:38:12": {"monitor.ip": "192.168.1.47", "monitor.status": " UP"}, "February 15 2019, 16:38:12": {"monitor.ip": "192.168.1.42", "monitor.status": " UP"}}

Answer 1

要在不覆盖现有内容的情况下继续向现有文件添加内容，应在“附加”模式下打开。 在您的代码中，您以“写入”模式打开。 这将打开文件进行写入，但将覆盖现有内容。

具体来说，您的代码中的这一行：

with open(name, 'w') as outfile:

您应该将打开模式从write（ 'w' ）更改为append（ 'a' ）。

with open(name, 'a') as outfile:

让我知道这是否可以解决您的问题。

Answer 2

下面是代码的精简版：

import os
from multiprocessing import Pool
import json
import datetime
import time

hosts = ["192.168.1.47", "8.8.8.8"]
MAX_NUMBER_OF_STATUS_CHECKS = 2
FILE_NAME = 'hosts_stats.json'


#
# counter and sleep were added in order to simulate scheduler activity  
#

def ping(host):
    status = os.system('ping  -o -c 3 {}'.format(host))
    return datetime.datetime.now().strftime("%B %d %Y, %H:%M:%S"), {"monitor.ip": host,
                                                                "monitor.status": 'UP' if status == 0 else 'DOWN'}


if __name__ == "__main__":
    p = Pool(processes=len(hosts))
    counter = 0
    if not os.path.exists(FILE_NAME):
        with open(FILE_NAME, 'w') as f:
            f.write('{}')
    while counter < MAX_NUMBER_OF_STATUS_CHECKS:
        result = p.map(ping, hosts)
        with open(FILE_NAME, 'rb+') as f:
            f.seek(-1, os.SEEK_END)
            f.truncate()
            for entry in result:
                _entry = '"{}":{},\n'.format(entry[0], json.dumps(entry[1]))
                f.writelines(_entry)
             f.write('}')
        counter += 1
        time.sleep(2)