这里以监控内存使用率为例，写的一个简单demo性程序，具体操作根据51reboot提供的教程写如下。
一、建库建表
创建falcon数据库：
mysql> create database falcon character set utf8; Query OK, 1 row affected (0.00 sec)
创建内存监控使用的表stat，表结构如下：
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端设置
首先我们设计一个web服务，实现如下功能：
完成监控页面展示
接受POST提交上来的数据
提供json数据GET接口
具体框架结构图如下：
目录结构如下：
web ├── flask_web.py └── templates └── mon.html
flask_web代码如下：
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)
这里使用的汇图JS为highcharts、highstock ，具体模板页面内容如下：
[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：这里的JS代码都直接使用互联网上的代码，如果主机无法连接互联网的，可以将上面的三段代取取下来，在templates 的同级目录创建static 目录，将下载下来的三个文件放到该目录，删除模板中三处引用javascript处的代码，使用当前注释的三段。
三、agent被监控端设置
web展示页面完成了，运行起来：python flask_web.py 监听在8888端口上。我们需要做一个agent来采集数据，并通过post方法请求flask_web页面，将数据上传写入数据库。这里以监控内存为例，具体监控代码如下：
#!/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):
#自动获取mon类里的所有getXXX方法，用XXX作为key，getXXX()的返回值作为value，构造字典
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 & 在被监控主机上运行，如果出于实验目的，想尽快的看到展示效果，可以将time.sleep(60) 改为time.sleep(2) ，这样每2秒就会取一次数据写入数据库。
访问 http://test.361way.com:8888 就可以看到我们的监控数据了：效果图如下
highcharts支持将按时间拖动，也支持按指定时间段查看。并且查看到的图片可以直接保存为png、jpg或pdf、csv等格式查看。
![[Web front-end] Node.js quick start](https://img.php.cn/upload/course/000/000/067/662b5d34ba7c0227.png)
