Python提示[Errno 32]Broken pipe导致线程crash错误解决方法

本文实例讲述了Python提示[Errno 32]Broken pipe导致线程crash错误解决方法。分享给大家供大家参考。具体方法如下：

1. 错误现象
ThreadingHTTPServer 实现的 http 服务，如果客户端在服务器返回前，主动断开连接，则服务器端会报 [Errno 32] Broken pipe 错，并导致处理线程 crash.
下面先看个例子,python 版本: 2.7
示例代码

代码如下：

#!/usr/bin/env python

#!coding=utf-8

  

import os

import time

import socket

import threading

from BaseHTTPServer import HTTPServer ,BaseHTTPRequestHandler

from SocketServer import ThreadingMixIn

  

class RequestHandler(BaseHTTPRequestHandler):

    def do_GET(self):

        """

        处理get请求

        """       

        query=self.path

        print "query: %s thread=%s" % (query, str(threading.current_thread()))

         

        #ret_str="<html>" + self.path + "<br>" + str(self.server) + "<br>" + str(self.responses) +  "</html>"

        ret_str="<html>" + self.path + "<br>" + str(self.server) +  "</html>"

         

        time.sleep(5)

         

        try:

            self.send_response(200)

            self.send_header('Content-type','text/html')

            self.end_headers()

            self.wfile.write(ret_str)

        except socket.error, e:

            print "socket.error : Connection broke. Aborting" + str(e)

            self.wfile._sock.close()  # close socket

            self.wfile._sock=None

            return False

        

        print "success prod query :%s" % (query)

        return True

  

#多线程处理

class ThreadingHTTPServer(ThreadingMixIn,HTTPServer):

    pass

     

if __name__ == '__main__':

    serveraddr = ('',9001)

 

    ser = ThreadingHTTPServer(serveraddr,RequestHandler)

    ser.serve_forever()

    sys.exit(0)

运行服务
./thread_http_server_error.py
第1次 curl ，等待返回

代码如下：

[~]$curl -s 'http://10.232.41.142:9001/hello1′

<html>/hello1<br><__main__.ThreadingHTTPServer instance at 0x37483b0></html>[~]$

此时服务器端输出日志如下：

$./thread_http_server_error.py

query: /hello1 thread=

search041142.sqa.cm4.tbsite.net C - [15/May/2014 15:02:27] “GET /hello1 HTTP/1.1″ 200 -

success prod query :/hello1

第2次 curl ，不等待返回，ctrl +C 来模拟客户端断开

代码如下：

[~]$curl -s 'http://10.232.41.142:9001/hello2′

[~]$ ctrl+C

此时服务器端输出日志如下：

代码如下：

query: /hello2 thread=

search041142.sqa.cm4.tbsite.net C - [15/May/2014 15:33:10] “GET /hello2 HTTP/1.1″ 200 -

socket.error : Connection broke. Aborting[Errno 32] Broken pipe

―――――――――――――-

Exception happened during processing of request from ('10.232.41.142′, 48769)

Traceback (most recent call last):

File “/home/wuzhu/tools/python_2_7_1/lib/python2.7/SocketServer.py”, line 582, in process_request_thread

self.finish_request(request, client_address)

File “/home/wuzhu/tools/python_2_7_1/lib/python2.7/SocketServer.py”, line 323, in finish_request

self.RequestHandlerClass(request, client_address, self)

File “/home/wuzhu/tools/python_2_7_1/lib/python2.7/SocketServer.py”, line 639, in __init__

self.handle()

File “/home/wuzhu/tools/python_2_7_1/lib/python2.7/BaseHTTPServer.py”, line 337, in handle

self.handle_one_request()

File “/home/wuzhu/tools/python_2_7_1/lib/python2.7/BaseHTTPServer.py”, line 326, in handle_one_request

 self.wfile.flush() #actually send the response if not already done.

File “/home/wuzhu/tools/python_2_7_1/lib/python2.7/socket.py”, line 303, in flush

self._sock.sendall(view[write_offset:write_offset+buffer_size])

AttributeError: 'NoneType' object has no attribute 'sendall'

2. 原因分析

“[Errno 32] Broken pipe “ 产生的原因还是比较明确的，由于 client 在服务器返回前主动断开连接，所以服务器在返回时写 socket 收到SIGPIPE报错。虽然在我们的程序中也对异常进行了处理，将handler 的 wfile._sock 对象close 掉，但python 的库里BaseHTTPServer.py中BaseHTTPRequestHandler 类的成员函数handle_one_request还是会直接调用 wfile.flush ，而没有判断 wfile 是否已经 close。

代码如下：

def handle_one_request(self):

    """Handle a single HTTP request.

 

    You normally don't need to override this method; see the class

    __doc__ string for information on how to handle specific HTTP

    commands such as GET and POST.

 

    """

    try:

        self.raw_requestline = self.rfile.readline(65537)

        if len(self.raw_requestline) > 65536:

            self.requestline = ''

            self.request_version = ''

            self.command = ''

            self.send_error(414)

            return

        if not self.raw_requestline:

            self.close_connection = 1

            return

        if not self.parse_request():

            # An error code has been sent, just exit

            return

        mname = 'do_' + self.command

        if not hasattr(self, mname):

            self.send_error(501, "Unsupported method (%r)" % self.command)

            return

        method = getattr(self, mname)

        method()

        #没有判断 wfile 是否已经 close 就直接调用 flush()

        self.wfile.flush() #actually send the response if not already done.

    except socket.timeout, e:

        #a read or a write timed out.  Discard this connection

        self.log_error("Request timed out: %r", e)

        self.close_connection = 1

        return

3. 解决办法

只要在RequestHandler重载其基类BaseHTTPRequestHandler的成员函数handle_one_reques（），在调用 wfile.flush() 前加上 wfile 是否已经 close 即可。

代码如下：

#!/usr/bin/env python

#!coding=utf-8

import os

import time

import socket

import threading

from BaseHTTPServer import HTTPServer ,BaseHTTPRequestHandler

from SocketServer import ThreadingMixIn


class RequestHandler(BaseHTTPRequestHandler):

     

    def handle_one_request(self):

        """Handle a single HTTP request.

 

        You normally don't need to override this method; see the class

        __doc__ string for information on how to handle specific HTTP

        commands such as GET and POST.

 

        """

        try:

            self.raw_requestline = self.rfile.readline(65537)

            if len(self.raw_requestline) > 65536:

                self.requestline = ''

                self.request_version = ''

                self.command = ''

                self.send_error(414)

                return

            if not self.raw_requestline:

                self.close_connection = 1

                return

            if not self.parse_request():

                # An error code has been sent, just exit

                return

            mname = 'do_' + self.command

            if not hasattr(self, mname):

                self.send_error(501, "Unsupported method (%r)" % self.command)

                return

            method = getattr(self, mname)

            print "before call do_Get"

            method()

            #增加 debug info 及 wfile 判断是否已经 close

            print "after call do_Get"

            if not self.wfile.closed:

                self.wfile.flush() #actually send the response if not already done.

            print "after wfile.flush()"

        except socket.timeout, e:

            #a read or a write timed out.  Discard this connection

            self.log_error("Request timed out: %r", e)

            self.close_connection = 1

            return

     

    def do_GET(self):

        """

        处理get请求

        """

        query=self.path

        print "query: %s thread=%s" % (query, str(threading.current_thread()))

 

        ret_str="<html>" + self.path + "<br>" + str(self.server) +  "</html>"

 

        time.sleep(5)

         

        try:

            self.send_response(200)

            self.send_header('Content-type','text/html')

            self.end_headers()          

            self.wfile.write(ret_str)

        except socket.error, e:

            print "socket.error : Connection broke. Aborting" + str(e)

            self.wfile._sock.close()

            self.wfile._sock=None

            return False

        

        print "success prod query :%s" % (query)

        return True

 

#多线程处理

class ThreadingHTTPServer(ThreadingMixIn,HTTPServer):

    pass

     

if __name__ == '__main__':

    serveraddr = ('',9001)

 

    ser = ThreadingHTTPServer(serveraddr,RequestHandler)

    ser.serve_forever()

    sys.exit(0)

运行服务
./thread_http_server.py
curl ，不等待返回，ctrl +C 来模拟客户端断开

代码如下：

[~]$curl -s 'http://10.232.41.142:9001/hello2'

[~]$ ctrl+C

此时服务器端输出日志如下：

代码如下：

$./thread_http_server.pybefore call do_Get

query: /hello2 thread=<Thread(Thread-1, started 1103210816)>

search041142.sqa.cm4.tbsite.net - - [15/May/2014 15:54:09] "GET /hello2 HTTP/1.1" 200 -

socket.error : Connection broke. Aborting[Errno 32] Broken pipe

after call do_Get

after wfile.flush()

希望本文所述对大家的Python程序设计有所帮助。

Python提示[Errno 32]Broken pipe导致线程crash错误解决方法

相关推荐