python下載時報錯 Errno 10060] A connection attempt failed because the connected party did not properly re

def downloadXml(isExists,filedir,filename):
    if not isExists:
        os.mkdir(filedir)
    local = os.path.join(filedir,filename)
    urllib2.urlopen(url,local)

報錯：

Traceback (most recent call last):
File "C:\Users\william\Desktop\nova xml\New folder\download_xml.py", line 95, in <module>
downloadXml(isExists,filedir,filename)
File "C:\Users\william\Desktop\nova xml\New folder\download_xml.py", line 80, in downloadXml
urllib.urlretrieve(url,local)
File "E:\Python27\lib\urllib.py", line 98, in urlretrieve
return opener.retrieve(url, filename, reporthook, data)
File "E:\Python27\lib\urllib.py", line 245, in retrieve
fp = self.open(url, data)
File "E:\Python27\lib\urllib.py", line 213, in open
return getattr(self, name)(url)
File "E:\Python27\lib\urllib.py", line 350, in open_http
h.endheaders(data)
File "E:\Python27\lib\httplib.py", line 1053, in endheaders
self._send_output(message_body)
File "E:\Python27\lib\httplib.py", line 897, in _send_output
self.send(msg)
File "E:\Python27\lib\httplib.py", line 859, in send
self.connect()
File "E:\Python27\lib\httplib.py", line 836, in connect
self.timeout, self.source_address)
File "E:\Python27\lib\socket.py", line 575, in create_connection
raise err
IOError: [Errno socket error] [Errno 10060] A connection attempt failed because the connected party did not properly respond after a period of time, or established connection failed because connected host has failed to respond
>>>

 

google查找答案，搜索：urlretrieve Errno 10060

在 https://segmentfault.com/q/1010000004386726中提到是：頻繁的訪問某個網站會被認爲是DOS攻擊，一般作了Rate-limit的網站都會中止響應一段時間，你能夠Catch這個Exception，sleep一段時間而後重試，也能夠根據重試的次數作exponential backup off。

 

想了一個簡單的辦法，就是每次下載之間加個延時，將代碼修改以下：

def downloadXml(isExists,filedir,filename):
    if not isExists:
        os.mkdir(filedir)
    local = os.path.join(filedir,filename)
    time.sleep(1)
    urllib.urlretrieve(url,local)

執行。 原本是在第80條左右的數據就開始time out，但如今一直執行到2300多條數據。惋惜，最後又time out。 

這裏，若延長延時，將1s改成5s等，雖然可能不會報錯，但我想，這樣，太費時間了。由於不報錯時，也要延時5s，不如等報錯時再延時重試。

因而，

def downloadXml(isExists,filedir,filename):
    if not isExists:
        os.makedirs(filedir)
    local = os.path.join(filedir,filename)
    try:
        urllib.urlretrieve(url,local)
    except Exception as e:
        time.sleep(5)
        urllib.urlretrieve(url,local) 

 這樣的話，發現會卡在某條數據，不向後執行。因此只好改成在某條數據上，最多重試10次。

def downloadXml(flag_exists,file_dir,file_name,xml_url):
    if not flag_exists:
        os.makedirs(file_dir)
    local = os.path.join(file_dir,file_name)
    try:
        urllib.urlretrieve(xml_url,local)
    except Exception as e:
        print e
        cur_try = 0
        total_try = 10
        if cur_try < total_try:
            cur_try +=1
            time.sleep(15)
            return downloadXml(flag_exists,file_dir,file_name,xml_url)
        else:
            raise Exception(e)

這樣執行後，果真再也不報錯，順利執行完了。但一想，有個問題，使用哪一個URL進行下載失敗，沒有記錄下來。因此又添加了將失敗的url寫入本地文本的功能。後面能夠查看，並手動執行。

def downloadXml(flag_exists,file_dir,file_name,xml_url):
    if not flag_exists:
        os.makedirs(file_dir)
    local = os.path.join(file_dir,file_name)
    try:
        urllib.urlretrieve(xml_url,local)
    except Exception as e:
        print 'the first error: ',e
        cur_try = 0
        total_try = 10
        if cur_try < total_try:
            cur_try +=1
            time.sleep(15)
            return downloadXml(flag_exists,file_dir,file_name,xml_url)
        else:
            print 'the last error: '
            with open(test_dir + 'error_url.txt','a') as f:
                f.write(xml_url)
            raise Exception(e)

遺憾的是，此次竟再沒有失敗的url了，多是網站這時流量不大。