python下Pool與target方法寫在同一個類里要注意的坑

在工作中遇到要對開發的接口做壓力測試，以前沒有做過開清楚什么壓測工具好用，正好接口不是什么復雜的接口，curl -X post "接口地址" --data-binary @二進制認證文件 OK！（@表示驗證數據是文件類型）

既然這樣那我就寫個腳本好了,腳本內容如下:

======================================================================
#!/usr/bin/evn python
#_coding:utf8_
from multiprocessing import Pool,Queue
import time,subprocess,os
class YaCe(object):
def init(self,api,binfile,maxpool,qu,maxrequest=100000,status="success"):
self.api = api
self.binfile = binfile
self.status = status
self.maxpool = maxpool
self.maxrequest = maxrequest
self.qu = qu
def prorequest(self):
for i in range(self.maxrequest):
self.qu.put(i)
print(i)
for i in range(int(self.maxpool)):
self.qu.put(None)
print("None")

def conumers(self,i):
    while True:
        data = self.qu.get(True)
        if data == None:
            print("進程%s任務完成..."%i)
            break
        else:
            command = subprocess.getoutput("time curl -X POST --connect-timeout 10 '%s'  --data-binary @%s"%(self.api,os.getcwd()+"/"+self.binfile))
            if self.status == "success":
                logfile = os.getcwd()+"/"+"headbeat.log"+"_%s"%date_time
                if "CgoyMDAwMDAwMDAw" in command:
                    print("進程%s__%s..."%(str(i),str(data)))
                    with open(logfile,"a") as f:
                        f.write(command+"\n")
                    f.close()
                else:
                                        print("進程%s__%s..."%(str(i),str(data)))
                    with open(logfile,"a") as f:
                        f.write("Faild\n")
                        f.write(command+"\n")
                    f.close()
            else:
                logfile = os.getcwd()+"/"+"roomlist.log"+"_%s"%date_time
                #print("time curl -X POST '%s'  --data-binary @%s"%(self.api,os.getcwd()+"/"+self.binfile))
                command = subprocess.getoutput("time curl -X POST '%s' --data-binary @%s"%(self.api,os.getcwd()+"/"+self.binfile))
                if "CAES+" in command:
                    print("進程%s__%s..."%(str(i),str(data)))
                    info = command.split('\n')[-3:]
                    info1 = "\n".join(info)
                    with open(logfile,"a") as f:
                        f.write(info1+"\n")
                    f.close()
                else:
                    print("進程%s__%s..."%(str(i),str(data)))
                    with open(logfile,"a") as f:
                        f.write("Faild\n")
                        f.write(command+"\n")
                    f.close()
def multirun(self):
    ps = int(int(self.maxpool) - 1)
    p = Pool(ps)
    for i in range(self.maxpool):
        print("開啟子進程%s"%i)
        p.apply_async(self.conumers,args=(self,i))
    print('等待所有添加的進程運行完畢。。。')
    p.close()
    p.join()
    endtime = time.strftime("%Y%m%d_%X",time.localtime())
    if self.status == "success":
        logfile = os.getcwd()+"/"+"headbeat.log"+"_%s"%date_time
    else:
        logfile = os.getcwd() + "/" + "roomlist.log"+"_%s"%date_time
    with open(logfile,"a") as f:
        f.write("============[%s]============\n"%endtime)
    f.close()
    print('End!!,PID:%s'% os.getpid())

if name == "main":
q = Queue()
Yc = YaCe('壓測接口','二進制證認文件',開多少個進程,queue(隊列),maxrequest=100（模擬測試多少次訪問）,status="faild"（這里因為測試的兩個接口，返回不一樣用status參數區分測試的接口的返回值處理）)
Yc.prorequest()
print("++++++")
global date_time
datetime = time.strftime("%Y%m%d%X",time.localtime())
Yc.multirun()

====================================================================================
問題
到這里寫完了，測試的問題來了，從腳本來看如果運行成功，會有多進程在處理隊列的輸出，可是結果的輸出確是如下：

01
2
3
4
5
6
7
8
9
None
None
++++++
開啟子進程0
開啟子進程1
等待所有添加的進程運行完畢。。。
End!!,PID:4819

原因
子進程conumers方法完全沒有運行，也沒有報錯這就尷尬了；查了大量的文檔資料；發現這個pool方法都使用了queue.Queue將task傳遞給工作進程。multiprocessing必須將數據序列化以在進程間傳遞。方法只有在模塊的頂層時才能被序列化，跟類綁定的方法不能被序列化，就會出現上面的異常 ; 那腫么辦，我不是一個輕易放棄的人，終于被我找到了方法;

注意
解決方作者是在python3下測試了，python2下用腳本的subprocess要換成value,command = commands.getstatusoutput

解決方法1（親測）
1.首先要看報錯，需要對腳本修改如下:
YaCe類下的multirun方法下修改
for i in range(self.maxpool):
print("開啟子進程%s"%i)
p.apply_async(self.conumers,args=(self,i))
為
for i in range(self.maxpool):
print("開啟子進程%s"%i)
res = p.apply_async(self.conumers,args=(self,i))
print(res.get)
這就可以看到報錯:
cPickle.PicklingError: Can't pickle <type 'instancemethod'>: attribute lookup builtin.instancemethod failed

2.解決方法如下在腳本中加一個新的函數
(1).def conumers_wrapper(cls_instance,i):
return cls_instance.conumers(i)

(2).修改YaCe下multirun方法
for i in range(self.maxpool):
print("開啟子進程%s"%i)
res = p.apply_async(self.conumers,args=(self,i))
print(res.get())
為
for i in range(self.maxpool):
print("開啟子進程%s"%i)
res = p.apply_async(conumers_wrapper,args=(self,i))
print(res.get)

問題解決了，運行一下腳本結果還有報錯：
RuntimeError: Queue objects should only be shared between processes through inheritance

原因
這里不可以用Queue,要改用Manager.Queue；因為進程之前的同共離用Queue會用問題；

完結
最終代碼如下:

==================================================================================
#!/usr/bin/evn python
#_coding:utf8_
from multiprocessing import Pool,Queue,Manager
import time,subprocess,os
class YaCe(object):
def init(self,api,binfile,maxpool,qu,maxrequest=100000,status="success"):
self.api = api
self.binfile = binfile
self.status = status
self.maxpool = maxpool
self.maxrequest = maxrequest
self.qu = qu
def prorequest(self):
for i in range(self.maxrequest):
self.qu.put(i)
print(i)
for i in range(int(self.maxpool)):
self.qu.put(None)
print("None")

def conumers(self,i):
    while True:
        data = self.qu.get(True)
        if data == None:
            print("進程%s任務完成..."%i)
            break
        else:
            #print("time curl -X POST '%s'  --data-binary @%s"%(self.api,os.getcwd()+"/"+self.binfile))
            command = subprocess.getoutput("time curl -X POST --connect-timeout 10 '%s'  --data-binary @%s"%(self.api,os.getcwd()+"/"+self.binfile))
            #command = subprocess.getoutput("time curl -X POST '%s'  --data-binary @%s"%(self.api,os.getcwd()+"/"+self.binfile))
            if self.status == "success":
                logfile = os.getcwd()+"/"+"headbeat.log"+"_%s"%date_time
                if "CgoyMDAwMDAwMDAw" in command:
                    print("進程%s__%s..."%(str(i),str(data)))
                    with open(logfile,"a") as f:
                        f.write(command+"\n")
                    f.close()
                else:
                    with open(logfile,"a") as f:
                        f.write("Faild\n")
                        f.write(command+"\n")
                    f.close()
            else:
                logfile = os.getcwd()+"/"+"roomlist.log"+"_%s"%date_time
                #print("time curl -X POST '%s'  --data-binary @%s"%(self.api,os.getcwd()+"/"+self.binfile))
                command = subprocess.getoutput("time curl -X POST --connect-timeout 10 '%s'  --data-binary @%s"%(self.api,os.getcwd()+"/"+self.binfile))
                #command = subprocess.getoutput("time curl -X POST '%s' --data-binary @%s"%(self.api,os.getcwd()+"/"+self.binfile))
                if "CAES+" in command:
                    print("進程%s__%s..."%(str(i),str(data)))
                    info = command.split('\n')[-3:]
                    info1 = "\n".join(info)
                    with open(logfile,"a") as f:
                        f.write(info1+"\n")
                    f.close()
                else:
                    print("進程%s__%s..."%(str(i),str(data)))
                    with open(logfile,"a") as f:
                        f.write("Faild\n")
                        f.write(command+"\n")
                    f.close()
def multirun(self):
    ps = int(int(self.maxpool) - 1)
    p = Pool(ps)
    for i in range(self.maxpool):
        print("開啟子進程%s"%i)
        p.apply_async(conumers_wrapper,args=(self,i))
    #print(res.get)
    print('等待所有添加的進程運行完畢。。。')
    p.close()
    p.join()
    endtime = time.strftime("%Y%m%d_%X",time.localtime())
    if self.status == "success":
        logfile = os.getcwd()+"/"+"headbeat.log"+"_%s"%date_time
    else:
        logfile = os.getcwd() + "/" + "roomlist.log"+"_%s"%date_time
    with open(logfile,"a") as f:
        f.write("============[%s]============\n"%endtime)
    f.close()
    print('End!!,PID:%s'% os.getpid())

def conumers_wrapper(cls_instance,i):
return cls_instance.conumers(i)

if name == "main":
q = Manager().Queue()
Yc = YaCe('壓測接口','二進制證認文件',開多少個進程,queue(隊列),maxrequest=100（模擬測試多少次訪問）,status="faild"（這里因為測試的兩個接口，返回不一樣用status參數區分測試的接口的返回值處理）)
Yc.prorequest()
print("++++++")
global date_time
datetime = time.strftime("%Y%m%d%X",time.localtime())
Yc.multirun()