用Python的Flask框架結合MySQL寫一個內存監(jiān)控程序

更新時間：2015年11月07日 18:00:17 投稿：goldensun

這篇文章主要介紹了用Python的Flask框架結合MySQL些一個內存監(jiān)控程序的例子,并且能將結果作簡單的圖形化顯示,需要的朋友可以參考下

這里以監(jiān)控內存使用率為例，寫的一個簡單demo性程序，具體操作根據51reboot提供的教程寫如下。

一、建庫建表

創(chuàng)建falcon數據庫：

mysql> create database falcon character set utf8;
Query OK, 1 row affected (0.00 sec)

創(chuàng)建內存監(jiān)控使用的表stat，表結構如下：

CREATE TABLE `stat` (
 `id` int(11) unsigned NOT NULL AUTO_INCREMENT,
 `host` varchar(256) DEFAULT NULL,
 `mem_free` int(11) DEFAULT NULL,
 `mem_usage` int(11) DEFAULT NULL,
 `mem_total` int(11) DEFAULT NULL,
 `load_avg` varchar(128) DEFAULT NULL,
 `time` bigint(11) DEFAULT NULL,
 PRIMARY KEY (`id`),
 KEY `host` (`host`(255))
) ENGINE=InnoDB AUTO_INCREMENT=0 DEFAULT CHARSET=utf8;

二、flask web端設置

首先我們設計一個web服務，實現如下功能：

完成監(jiān)控頁面展示
接受POST提交上來的數據
提供json數據GET接口
具體框架結構圖如下：

2015117174700956.png (907×380)

目錄結構如下：

web
├── flask_web.py
└── templates
 └── mon.html

flask_web代碼如下：

import MySQLdb as mysql
import json
from flask import Flask, request, render_template
app = Flask(__name__)
db = mysql.connect(user="361way", passwd="123456", \
  db="falcon", charset="utf8")
db.autocommit(True)
c = db.cursor()
@app.route("/", methods=["GET", "POST"])
def hello():
 sql = ""
 if request.method == "POST":
  data = request.json
  try:
   sql = "INSERT INTO `stat` (`host`,`mem_free`,`mem_usage`,`mem_total`,`load_avg`,`time`) VALUES('%s', '%d', '%d', '%d', '%s', '%d')" % (data['Host'], data['MemFree'], data['MemUsage'], data['MemTotal'], data['LoadAvg'], int(data['Time']))
   ret = c.execute(sql)
  except mysql.IntegrityError:
   pass
  return "OK"
 else:
  return render_template("mon.html")
@app.route("/data", methods=["GET"])
def getdata():
 c.execute("SELECT `time`,`mem_usage` FROM `stat`")
 ones = [[i[0]*1000, i[1]] for i in c.fetchall()]
 return "%s(%s);" % (request.args.get('callback'), json.dumps(ones))
if __name__ == "__main__":
 app.run(host="0.0.0.0", port=8888, debug=True)

這里使用的匯圖JS為highcharts、highstock ，具體模板頁面內容如下：

[root@91it templates]# cat mon.html

<title>memory monitor</title>
<!DOCTYPE HTML>
<html>
 <head>
  <meta http-equiv="Content-Type" content="text/html; charset=utf-8">
  <title>Highstock Example</title>
  <!-- <script type="text/javascript" src="{{ url_for('static', filename='jquery.min.js') }}"></script> -->
  <script type="text/javascript" src="http://ajax.useso.com/ajax/libs/jquery/1.8.2/jquery.min.js"></script>
  <style type="text/css">
${demo.css}
  </style>
  <script type="text/javascript">
$(function () {
 $.getJSON('/data?callback=?', function (data) {
  // Create the chart
  $('#container').highcharts('StockChart', {
   rangeSelector: {
    inputEnabled: $('#container').width() > 480,
    selected: 1
   },
   title: {
    text: 'memory monitor'
   },
   series: [{
    name: 'memory monitor',
    data: data,
    type: 'spline',
    tooltip: {
     valueDecimals: 2
    }
   }]
  });
 });
});
  </script>
 </head>
 <body>
<!-- <script src="{{ url_for('static', filename='highstock.js') }}"></script> -->
<script src="http://cdnjs.cloudflare.com/ajax/libs/highstock/2.0.4/highstock.js"></script>
<!-- <script src="{{ url_for('static', filename='exporting.js') }}"></script> -->
<script src="http://code.highcharts.com/modules/exporting.js"></script>
<div id="container" style="height: 400px"></div>
 </body>
</html>

注：這里的JS代碼都直接使用互聯(lián)網上的代碼，如果主機無法連接互聯(lián)網的，可以將上面的三段代取取下來，在templates 的同級目錄創(chuàng)建static 目錄，將下載下來的三個文件放到該目錄，刪除模板中三處引用javascript處的代碼，使用當前注釋的三段。

三、agent被監(jiān)控端設置

web展示頁面完成了，運行起來：python flask_web.py 監(jiān)聽在8888端口上。我們需要做一個agent來采集數據，并通過post方法請求flask_web頁面，將數據上傳寫入數據庫。這里以監(jiān)控內存為例，具體監(jiān)控代碼如下：

#!/usr/bin/env python
#coding=utf-8
import inspect
import time
import urllib, urllib2
import json
import socket
class mon:
 def __init__(self):
  self.data = {}
 def getTime(self):
  return str(int(time.time()) + 8 * 3600)
 def getHost(self):
  return socket.gethostname()
 def getLoadAvg(self):
  with open('/proc/loadavg') as load_open:
   a = load_open.read().split()[:3]
   return ','.join(a)
 def getMemTotal(self):
  with open('/proc/meminfo') as mem_open:
   a = int(mem_open.readline().split()[1])
   return a / 1024
 def getMemUsage(self, noBufferCache=True):
  if noBufferCache:
   with open('/proc/meminfo') as mem_open:
    T = int(mem_open.readline().split()[1])
    F = int(mem_open.readline().split()[1])
    B = int(mem_open.readline().split()[1])
    C = int(mem_open.readline().split()[1])
    return (T-F-B-C)/1024
  else:
   with open('/proc/meminfo') as mem_open:
    a = int(mem_open.readline().split()[1]) - int(mem_open.readline().split()[1])
    return a / 1024
 def getMemFree(self, noBufferCache=True):
  if noBufferCache:
   with open('/proc/meminfo') as mem_open:
    T = int(mem_open.readline().split()[1])
    F = int(mem_open.readline().split()[1])
    B = int(mem_open.readline().split()[1])
    C = int(mem_open.readline().split()[1])
    return (F+B+C)/1024
  else:
   with open('/proc/meminfo') as mem_open:
    mem_open.readline()
    a = int(mem_open.readline().split()[1])
    return a / 1024
 def runAllGet(self):
  #自動獲取mon類里的所有getXXX方法，用XXX作為key，getXXX()的返回值作為value，構造字典
  for fun in inspect.getmembers(self, predicate=inspect.ismethod):
   if fun[0][:3] == 'get':
    self.data[fun[0][3:]] = fun[1]()
  return self.data
if __name__ == "__main__":
 while True:
  m = mon()
  data = m.runAllGet()
  print data
  req = urllib2.Request("http://test.361way.com:8888", json.dumps(data), {'Content-Type': 'application/json'})
  f = urllib2.urlopen(req)
  response = f.read()
  print response
  f.close()
  time.sleep(60)

nohup python moniItems.py >/dev/null 2>&1 & 在被監(jiān)控主機上運行，如果出于實驗目的，想盡快的看到展示效果，可以將time.sleep(60) 改為time.sleep(2) ，這樣每2秒就會取一次數據寫入數據庫。

訪問 http://test.361way.com:8888 就可以看到我們的監(jiān)控數據了：效果圖如下

2015117175842218.png (793×435)