脚本之家,脚本语言编程技术及教程分享平台!
分类导航

Python|VBS|Ruby|Lua|perl|VBA|Golang|PowerShell|Erlang|autoit|Dos|bat|

服务器之家 - 脚本之家 - Python - python实现多线程网页下载器

python实现多线程网页下载器

2021-01-31 00:34赖勇浩 Python

这篇文章主要为大家详细介绍了python实现一个多线程网页下载器,具有一定的参考价值,感兴趣的小伙伴们可以参考一下

本文为大家分享了python实现的一个多线程网页下载器,供大家参考,具体内容如下

这是一个有着真实需求的实现,我的用途是拿它来通过 HTTP 方式向服务器提交游戏数据。把它放上来也是想大家帮忙挑刺,找找 bug,让它工作得更好。

keywords:python,http,multi-threads,thread,threading,httplib,urllib,urllib2,Queue,http pool,httppool

废话少说,上源码:

?
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
# -*- coding:utf-8 -*-
import urllib, httplib
import thread
import time
from Queue import Queue, Empty, Full
HEADERS = {"Content-type": "application/x-www-form-urlencoded",
            'Accept-Language':'zh-cn',
            'User-Agent': 'Mozilla/4.0 (compatible; MSIE 6.0;Windows NT 5.0)',
            "Accept": "text/plain"}
UNEXPECTED_ERROR = -1
POST = 'POST'
GET = 'GET'
def base_log(msg):
  print msg
def base_fail_op(task, status, log):
  log('fail op. task = %s, status = %d'%(str(task), status))
def get_remote_data(tasks, results, fail_op = base_fail_op, log = base_log):
  while True:
    task = tasks.get()
    try:
      tid = task['id']
      hpt = task['conn_args'] # hpt <= host:port, timeout
    except KeyError, e:
      log(str(e))
      continue
    log('thread_%s doing task %d'%(thread.get_ident(), tid))
    #log('hpt = ' + str(hpt))
    conn = httplib.HTTPConnection(**hpt)
       
    try:
      params = task['params']
    except KeyError, e:
      params = {}
    params = urllib.urlencode(params)
    #log('params = ' + params)
     
    try:
      method = task['method']
    except KeyError:
      method = 'GET'
    #log('method = ' + method)
     
    try:
      url = task['url']
    except KeyError:
      url = '/'
    #log('url = ' + url)
     
    headers = HEADERS
    try:
      tmp = task['headers']
    except KeyError, e:
      tmp = {}
    headers.update(tmp)
    #log('headers = ' + str(headers))
    headers['Content-Length'] = len(params)
     
    try:
      if method == POST:
        conn.request(method, url, params, headers)
      else:
        conn.request(method, url + params)
      response = conn.getresponse()
    except Exception, e:
      log('request failed. method = %s, url = %s, params = %s headers = %s'%(
            method, url, params, headers))
      log(str(e))
      fail_op(task, UNEXPECTED_ERROR, log)
      continue
       
    if response.status != httplib.OK:
      fail_op(task, response.status, log)
      continue
       
    data = response.read()
    results.put((tid, data), True)
     
class HttpPool(object):
  def __init__(self, threads_count, fail_op, log):
    self._tasks = Queue()
    self._results = Queue()
     
    for i in xrange(threads_count):
      thread.start_new_thread(get_remote_data, 
                              (self._tasks, self._results, fail_op, log))
       
  def add_task(self, tid, host, url, params, headers = {}, method = 'GET', timeout = None):
    task = {
      'id' : tid,
      'conn_args' : {'host' : host} if timeout is None else {'host' : host, 'timeout' : timeout},
      'headers' : headers,
      'url' : url,
      'params' : params,
      'method' : method,
      }
    try:
      self._tasks.put_nowait(task)
    except Full:
      return False
    return True
     
  def get_results(self):
    results = []
    while True:
      try:
        res = self._results.get_nowait()
      except Empty:
        break
      results.append(res)
    return results
     
def test_google(task_count, threads_count):
  hp = HttpPool(threads_count, base_fail_op, base_log)
  for i in xrange(task_count):
    if hp.add_task(i,
        'www.google.cn',
        '/search?',
        {'q' : 'lai'},
#        method = 'POST'
        ):
      print 'add task successed.'
       
  while True:
    results = hp.get_results()
    if not results:
      time.sleep(1.0 * random.random())
    for i in results:
      print i[0], len(i[1])
#      print unicode(i[1], 'gb18030')
       
if __name__ == '__main__':
  import sys, random
  task_count, threads_count = int(sys.argv[1]), int(sys.argv[2])
  test_google(task_count, threads_count)

 有兴趣想尝试运行的朋友,可以把它保存为 xxxx.py,然后执行 python xxxx.py 10 4,其中 10 表示向 google.cn 请求 10 次查询,4 表示由 4 条线程来执行这些任务。

以上就是本文的全部内容,希望对大家的学习有所帮助,也希望大家多多支持服务器之家。

原文链接:https://blog.csdn.net/gzlaiyonghao/article/details/4083852

延伸 · 阅读

精彩推荐