將子進程管理到Linux中的一個文件中

Question

我在靠牆試圖讓我的代碼正常工作。實質上，我寫了一個將由cron調用的python腳本。該腳本每週運行一次以執行數據庫維護。我的python腳本將調用執行實際維護的perl腳本。我必須這樣構建它，因爲perl腳本將總共運行9次。有3個不同類別的數據庫項目，每個類別需要3個不同的來自Perl腳本的動作。如果任何類別的單個操作失敗，腳本將從該類別中斷開並轉到下一個操作（每個操作都取決於之前的操作）。

我的腳本無法正常執行，我不知道爲什麼。我試圖解決它，但我的日誌邏輯不正常工作。我在我的日誌文件中獲得的唯一輸出是簡單的「打印」命令，我已經寫入腳本中進行記錄和格式化。

我可以直接從CLI運行perl腳本，但是從我的python腳本調用時它無法正常運行。任何人都可以指出我正確的方向嗎？

編輯： 在回答一個問題，我沒有很好的解釋如何perl腳本失敗。我沒有從perl腳本獲取stdout或stderr到我的日誌文件中，所以我不知道它爲什麼失敗。 我沒有創建perl腳本，它提供了我正在管理的軟件套件。

這裏的日誌文件輸出：

------------------------------------------------------------------------------------------------------ 
Weekly Voyence archival, deletion, and purging of jobs, events, and revisions beginning at 14:46:11 
Block failed, continuing to next block 
------ 
Block failed, continuing to next block 
------ 
Block failed, continuing to next block 
------ 
Weekly Voyence archival, deletion, and purging of jobs, events, and revisions complete at 14:46:11 

這裏是從CLI運行perl腳本（沒有錯誤）輸出：

Script started at Mon Nov 7 14:59:53 2016 

Archving/Pruning 0 Parent jobs older than 90 days... 
Archving/Pruning 0 Child Jobs older than 90 days... 

No Records avaialble for archive..jobs Exiting 
Script Completed. 

The database utility console log can be found at /opt/voyence/tools/db- utility/logs/dbutil_console.log 

Script exited at Mon Nov 7 14:59:58 2016 

下面是python腳本：

#! /usr/bin/python 
import sys 
import time 
import os 
import subprocess 
def SubProcessCaller(PATH,CallLoad,LogObj,LOGFILE): 
    try: 
     # subprocess.Popen(["/usr/bin/perl", "-i", "/opt/voyence/tools/db- utility/database-utility.pl", CallLoad], stderr=LogObj.write, stdout=LogObj.write, shell=true) 
     concatvar = "/usr/bin/perl -I /opt/voyence/tools/db-utility/common /opt/voyence/tools/db-utility/database-utility.pl" + CallLoad + " >> " + LOGFILE 
     subprocess.check_output(concatvar.split(), shell=True) 
     return True 
    except: 
     LogObj.write("Block failed, continuing to next block" "\n") 
     return False 

if __name__ == "__main__": 

    #DECLARE VARIABLES AND OBJECTS 
    TIME = time.strftime("%H:%M:%S") 
    PATH = "/opt/voyence/tools/db-utility/database-utility.pl" 
    DATE = time.strftime("%Y%m%d") 
    LOGFILE = "/var/log/voyence-archive/" + DATE + "voyence-archive.log" 
    LOG = open(LOGFILE, "a+") 
    #CREATE NEW LOG FILE 
    LOG.write("------------------------------------------------------------------------------------------------------\n") 
    LOG.write("Weekly Voyence archival, deletion, and purging of jobs, events, and revisions beginning at " + TIME + "\n") 
    #JOB ARCHIVAL, DELETION, AND PURGING 
    JobActionsDict = [" archive jobs 90"," delete jobs 90"," purge jobs 275"] 
    #EVENT ARCHIVAL, DELETION, AND PURGING 
    EventActionsDict = [" archive events all 90"," delete events all 90"," purge events all 275"] 
    #REVISION ARCHIVAL, DELETION, AND PURGING 
    RevisionActionsDict = [" archive revisions 40"," purge revisions 60"," delete revisions '3 months' 40"] 

    ActionsTuple = (JobActionsDict, EventActionsDict, RevisionActionsDict) 

    for dict in ActionsTuple: 
     for item in dict: 
      SPCBool = SubProcessCaller(PATH,item,LOG,LOGFILE) 
      if SPCBool == False: 
       break 
     LOG.write("------\n") 
    #CLOSE AFTER ALL LOGS HAVE BEEN WRITTEN 
    LOG.write("Weekly Voyence archival, deletion, and purging of jobs, events, and revisions complete at " + TIME + "\n") 
    LOG.close() 

Answer 1

concatvar = "/usr/bin/perl -I /opt/voyence/tools/db-utility/common /opt/voyence/tools/db-utility/database-utility.pl" + CallLoad + " >> " + LOGFILE 

本小節將您的程序名稱（database-utility.pl）與CallLoad變量的內容進行比較 - 不要在它們之間放置空格。因此，除非CallLoad中的值以空格開頭，否則您實際上正在尋找名爲database-utility.plWhateverIsInCallLoad的程序。

Answer 2

未經測試，但更慣用的Python。主要更改是在調用Perl腳本時完全繞過外殼，並記錄可能由subprocess.call引發的任何錯誤以幫助調試問題。 （考慮使用logging模塊代替，但已經有足夠的變化。）

#! /usr/bin/python 
import sys 
import time 
import os 
import subprocess 

def subprocess_caller(path, call_load, log_obj): 
    subprocess.call(["/usr/bin/perl", 
        "-I", 
        "/opt/voyence/tools/db-utility/common", 
        path, 
        call_load], 
        stdout=log_obj) 

log_header = """\ 
------------------------------------------------------------------------------------------------------ 
Weekly Voyence archival, deletion, and purging of jobs, events, and revisions beginning at %s 
""" %(time.strftime("%H:%M:%S"),) 

if __name__ == "__main__": 

    #declare variables and objects 
    path = "/opt/voyence/tools/db-utility/database-utility.pl" 
    logfile = time.strftime("/var/log/voyence-archive/%Y%m%dvoyence-archive.log") 

    #create new log file 
    with open(logfile, "a+") as log: 
     log.write(hog_header) 
     #job archival, deletion, and purging 
     job_actions = [" archive jobs 90"," delete jobs 90"," purge jobs 275"] 
     #event archival, deletion, and purging 
     event_actions = [" archive events all 90"," delete events all 90"," purge events all 275"] 
     #revision archival, deletion, and purging 
     revision_actions = [" archive revisions 40"," purge revisions 60"," delete revisions '3 months' 40"] 

     actions = job_actions + event_actions + revision_action: 

     for action_type in actions: 
      for item in action_type: 
       try: 
        subprocess_caller(path, item, log) 
       except Exception as exc: 
        log_obj.write(exc + "\n") 
        log_obj.write("Block failed, continuing to next block\n") 
        break 
       log.write("------\n") 

     log.write("Weekly Voyence archival, deletion, and purging of jobs, events, and revisions complete at %s\n" % 
        (time.strftime("%H:%M:%S"),))