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Webpy使用教程
Web.py 是一个轻量级的 Python Web 框架，它以简单、直接而闻名，旨在让 Web 应用开发变得快速而容易。Web.py的核心代码库非常小巧，只提供构建 Web 应用所需的基本功能，如 URL 路由、请求/响应处理、模板渲染等。这让它非常容易学习和上手。
来搜狐后，这里做的系统几乎都是 webpy + twsited 写的。所以，有必要好好学习一下这两个东西了。从今天开始介绍Web.py。
Server¶
安装
sudo pip install web.py第一个demo
#coding: utf-8
import web
urls = (
'/', 'Index'
)
class Index:
def GET(self):
return 'Hello, world ! GET \n'
def POST(self):
return 'Hello, world ! POST \n'
def start():
app = web.application(urls, globals())
app.run()
if __name__ == '__main__':
start()启动
python webpy_test.py 0.0.0.0:4321GET 测试
>>> curl http://localhost:4321
>>> Hello, world ! GETPOST 测试
>>> curl http://localhost:4321 -d't=1'
>>> Hello, world ! POST总结 1. url 简单的就是字符串，和django很类似 2. 对于Controller而言，get请求执行GET方法，post请求执行POST方法，估计PUT和DELETE等也是一样的
Template¶
公司直接用的jinja。jinja和django template的太相似了。说说如果在webpy中使用jinja。
webpy_jinja.py
#coding: utf-8
import web
from web.contrib.template import render_jinja
urls = (
'/', 'hello'
)
app = web.application(urls, globals())
render = render_jinja(
'templates', # 模板位置.
encoding = 'utf-8', # 编码.
)
class Hello:
def GET(self):
return render.hello(value='hello, World! GET')
def POST(self):
return web.seeother('/')
if __name__ == "__main__":
app.run()hello.html
{{value}}跳转 - Hello 的 GET 请求就是直接的服务器渲染页面，发送给客户端(一般是browser) - Hello 的 POST 就是服务器端返回给客户端http code，然后客户端直接进行跳转，再次跳转到Hello的GET上
数据库操作¶
得到连接
db = web.database(dbn='postgres', db='mydata', user='dbuser', pw='')简单查询
db.select(
'table_name', # 表名
vars = {'name'='py'}, # 用来填充查询条件, 这个例子中对应的就是where的$name
where = 'username=$name', # 查询条件
what = 'id, username', # 表示你要查询的field是哪些，默认为*。这个例子中表示查询id和username字段
order = 'age DESC', # 排序方式，表示按照年龄的倒排
group = 'gender', # 表示按照gender分组
limit = 10, # 查询10条
offset = 10, # 表示从第10条开始
_test = True/False # 日志打印出查询语句，True表示打印，False表示不打印。一般debug环境设置为True
)高级查询
db.query("SELECT COUNT(*) AS total_users FROM users")
# 有sql注入，可以修改为下面的
db.query("SELECT * FROM user WHERE user.id = %s" % 10)
# 没有sql注入
db.query("SELECT * FROM user WHERE user.id = $id", vars = {'id': 10 }) 更新
# 把id=10的记录的username修改为pengyi
db.update('table_name', where="id = 10", username = "pengyi") 插入
db.insert('table_name', username="Poy") # 插入一条记录，设置username=Poy删除
db.delete('table_name', where="id = 10") # 删除id=10的记录事务
with db.transaction():
db.insert('table_name', name='py')
db.insert('table_name', name='pengyi')cgi配置¶
安装flug
sudo pip install flupwebpy启动代码中写
def run_cgi(func, addr):
return flups.WSGIServer(func, multiplexed=False, bindAddress=addr).run()
def start_fcgi():
app = web.application(urls, globals())
web.wsgi.runwsgi = lambda func, addr = None: flups.WSGIServer(func, multiplexed=False, bindAddress=addr).run()
app.run()性能测试¶
webpy的性能真的是不敢恭维啊
代码如下：
#coding: utf-8
import web
urls = (
'/', 'Index'
)
class Index:
def GET(self):
return 'Hello, world !\n'
def start():
app = web.application(urls, globals())
app.run()
if __name__ == '__main__':
start()利用apache 的ab进行压力测试，10并发1000次请求：
>>> ab -c 10 -n 1000 http://192.168.95.222:4321/
>>>
>>> This is ApacheBench, Version 2.3 <$Revision: 655654 $>
>>> Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/
>>> Licensed to The Apache Software Foundation, http://www.apache.org/
>>>
>>> Benchmarking 192.168.95.222 (be patient)
>>> Completed 100 requests
>>> Completed 200 requests
>>> Completed 300 requests
>>> Completed 400 requests
>>> Completed 500 requests
>>> Completed 600 requests
>>> Completed 700 requests
>>> Completed 800 requests
>>> Completed 900 requests
>>> Completed 1000 requests
>>> Finished 1000 requests
>>>
>>> Server Software: CherryPy/3.1.2
>>> Server Hostname: 192.168.95.222
>>> Server Port: 4321
>>>
>>> Document Path: /
>>> Document Length: 16 bytes
>>>
>>> Concurrency Level: 10
>>> Time taken for tests: 6.269 seconds
>>> Complete requests: 1000
>>> Failed requests: 0
>>> Write errors: 0
>>> Total transferred: 108000 bytes
>>> HTML transferred: 16000 bytes
>>> Requests per second: 159.51 [#/sec] (mean)
>>> Time per request: 62.691 [ms] (mean)
>>> Time per request: 6.269 [ms] (mean, across all concurrent requests)
>>> Transfer rate: 16.82 [Kbytes/sec] received
>>>
>>> Connection Times (ms)
>>> min mean[+/-sd] median max
>>> Connect: 1 1 0.3 1 5
>>> Processing: 29 61 14.7 61 373
>>> Waiting: 29 61 14.7 61 372
>>> Total: 30 62 14.7 62 374
>>>
>>> Percentage of the requests served within a certain time (ms)
>>> 50% 62
>>> 66% 64
>>> 75% 65
>>> 80% 66
>>> 90% 68
>>> 95% 70
>>> 98% 71
>>> 99% 73
>>> 100% 374 (longest request)平均每秒只能在160s，太低了。
再来看 100并发，2000请求
>>> ab -c 100 -n 2000 http://192.168.95.222:4321/
>>>
>>> This is ApacheBench, Version 2.3 <$Revision: 655654 $>
>>> Copyright 1996 Adam Twiss, Zeus Technology Ltd, http://www.zeustech.net/
>>> Licensed to The Apache Software Foundation, http://www.apache.org/
>>>
>>> Benchmarking 192.168.95.222 (be patient)
>>> Completed 200 requests
>>> Completed 400 requests
>>> Completed 600 requests
>>> Completed 800 requests
>>> Completed 1000 requests
>>> Completed 1200 requests
>>> Completed 1400 requests
>>> Completed 1600 requests
>>> Completed 1800 requests
>>> Completed 2000 requests
>>> Finished 2000 requests
>>>
>>>
>>> Server Software: CherryPy/3.1.2
>>> Server Hostname: 192.168.95.222
>>> Server Port: 4321
>>>
>>> Document Path: /
>>> Document Length: 20 bytes
>>>
>>> Concurrency Level: 100
>>> Time taken for tests: 15.158 seconds
>>> Complete requests: 2000
>>> Failed requests: 0
>>> Write errors: 0
>>> Total transferred: 224000 bytes
>>> HTML transferred: 40000 bytes
>>> Requests per second: 131.94 [#/sec] (mean)
>>> Time per request: 757.902 [ms] (mean)
>>> Time per request: 7.579 [ms] (mean, across all concurrent requests)
>>> Transfer rate: 14.43 [Kbytes/sec] received
>>>
>>> Connection Times (ms)
>>> min mean[+/-sd] median max
>>> Connect: 1 37 203.5 1 1207
>>> Processing: 58 707 915.3 640 6597
>>> Waiting: 57 707 915.3 639 6596
>>> Total: 61 744 1076.6 641 7802
>>>
>>> Percentage of the requests served within a certain time (ms)
>>> 50% 641
>>> 66% 647
>>> 75% 650
>>> 80% 652
>>> 90% 667
>>> 95% 2641
>>> 98% 7173
>>> 99% 7674
>>> 100% 7802 (longest request)