python problems

[chef]

arrrgghhhh I'm writing a python script that effectively logs onto a Helpdesk System, retrieves a file, logs onto the ftp server, creates the directories and copies it across or uploads the file from the FTP server to the helpdesk

i'm getting an error in teardown() of
"global name 'ftp' is not defined "
but I can't for the life of me work out why it isn't picking up the global ftp variable..

any help much appreciated

from ConfigParser import ConfigParser
from optparse import OptionParser
import logging
import sys
import ctypes
import pickle
import os
import errno

from pyars import cars, erars
from ftplib import FTP
 
global ars
global ftp

def setup(server, user, password, verbose = False):
    global ars
    ars = erars.erARS()
    if verbose:
        ars.logger.setLevel(logging.DEBUG)
    else:
        ars.logger.setLevel(logging.INFO) 
    c=ars.Login(server, user, password,
#                charSet='Windows-1252'
#                charSet='UTF-8'
                charSet = 'iso8859-1'
                )
    if ars.errnr > 1:
        ars.logger.error('Could not login to server!')
        sys.exit(2)

def ftpSetup(server, user, password, path):
    global ftp
    
    ### open FTP connection
    ftp = FTP(server)
    try:
        ftp.login(user, password)
        ftp.cwd(path)
    except ftplib.error_perm:
        print ('Error logging in to ftp server %s with user %s' % (server,
                                                                  user))

def teardown():
    global ars 
    global ftp
    
    ftp.quit()
    ars.Logoff()

def changeToOrCreateFtpDir(directory):
    '''try to change to a directory; if it fails, create the directory and
change to it.'''
    global ftp
    
    try:
        ftp.cwd(directory)
    except ftplib.error_perm:
        ftp.mkd(directory)
        ftp.cwd(directory)

def transferAttachToResolve(worklogEntry,
                     location):
    '''transferAttachToResolve will receive the path information on the ftp server,
retrieve the file from there and add it as an attachment to the worklog.
Input:
'''
    path = '/var/tmp/resolve'
    (location, filename) = os.path.split(location)
    try:
        ftp.cwd(location)
    except ftplib.error_perm:
        print ('Error changing to ftp directory %s' % location)
        return
    
    filename = '%s/%s' % (path, filename)
    fileHandle = open(filename, 'wb')
    ftp.retrbinary("RETR " + filename, fileHandle.write)
    fileHandle.close()
    
    result = ars.SetEntry('RESOLVE:CASE:WRKLG:Worklog', entryId, 
                          {800600012l: (filename, None, None, filename)})
    if ars.errnr > 1:
        print ('Error adding attachment %s to worklog %s' % (filename,
                                                             entryId))

def transferAttachToMotto(worklogEntry,
                       fileName,
                       product,
                       caseNumber,
                       prontoID = ''):
    '''transferAttachToMotto takes the attachment from fieldId 800600012
from the worklog, stores it under the filename in /var/tmp and transfers
it to the Motto ftp server.
If we receive a prontoID, it is not an INFOADD, but an INFORESPONSE message. The
only difference is the ftp path where we store the attachment.
Input: worklogEntry: entryId of worklog
       fileName: name for temporary file
       product: RESOLVE product code
       caseNumber: caseNumber of the worklog
       prontoID (optional) if handed over is used to generate the ftp path
Output: /'''

    global ars
    global ftp
    
    fileName = "/var/tmp/resolve/%s" % fileName
    ### prepare a structure for the attachment
    loc = cars.ARLocStruct()
    loc.locType = cars.AR_LOC_FILENAME
    loc.u.filename = fileName
      
    att = ars.GetEntryBLOB ('RESOLVE:CASE:WRKLG:Worklog', worklogEntry, 
                            800600012, 
                            loc)
    if ars.errnr > 1:
        print ars.statusText()
        return

    ### open the file to read it as a file like object
    fileHandle = open(fileName, "r")
    
    ### create the required folder structure
    changeToOrCreateFtpDir(product)
    changeToOrCreateFtpDir(caseNumber)

    if prontoId != '':
        changeToOrCreateFtpDir(prontoId)
        changeToOrCreateFtpDir('answer')    
                
    ### save file like object to the ftp path
    ftp.storbinary("STOR " + fileName, fileHandle)
    fileHandle.close()

def main():
    
    usage = '''This tool handles the ftp transfer between RESOLVE and Motto.

It supports the upload (from Motto to RESOLVE, please use -l and -w) as well as
the download (from RESOLVE to Motto, indicated by not using -l!).
 
usage: %prog [options]''' 

    parser = OptionParser()
    parser.add_option("-w", "--worklog",  default='',
                          action="store", type="string", dest="worklog", help="worklog ID")
    parser.add_option("-c", "--case", default='',
                          action="store", type="string", dest="case", help="case number")
    parser.add_option("-m", "--productCode", default='',
                          action="store", type="string", dest="productCode", help="PDM Product Code")
    parser.add_option("-p", "--path", default='',
                          action="store", type="string", dest="path", help="complete FTP filepath for output")
    parser.add_option("-o", "--outputFile", default='attachment.txt',
                          action="store", type="string", dest="outputFile", help="filename for output")
    parser.add_option("-i", "--prontoID", default='',
                      action="store", type="string", dest="prontoID", help="Pronto Action ID") 
    parser.add_option("-l", "--location", default='',
                      action="store", type="string", dest="location", help="ftppath of attachment to be retrieved")
    parser.add_option("-v", "--verbose", action="store_true", default=False,
                          dest="verbose", help="verbose debugging output")
    
    (options, args) = parser.parse_args()
    
    config = ConfigParser ()
    config.read ("/global/resolve/programs/conf/api.conf")
    resolveServer = config.get ('ARS', 'ServerName')
    resolvePort = config.get ('ARS', 'ARServerPort')
    resolveUser = config.get ('ARS', 'UserName')
    resolvePwd = config.get ('ARS', 'Password')
    
    ftpServer = config.get ('Motto', 'ftpServer')
    ftpUser = config.get ('Motto', 'ftpUser')
    ftpPwd = config.get ('Motto', 'ftpPwd')
    ftpRootDir = config.get ('Motto', 'ftpRootDir')
    
    try:
        setup('%s:%s' % (resolveServer, resolvePort),
              resolveUser, resolvePwd, options.verbose)

        ftpSetup(ftpServer, ftpUser, ftpPwd, ftpRootDir)
        if options.location != '':
            transferAttachToResolve(options.worklog,
                             options.location)
        else:
            transferAttachToMotto(options.worklog,
                               options.outputFile,
                               options.productCode,
                               options.case,
                               options.prontoID)
    finally:
        teardown()

if __name__ == "__main__":
    main()

[DimPrawn]

Python

Looks like a cross between VB and Pascal.

Apart from that, I know nothing

[chef]

more info here on python

[crack_ho]

Is your ars populated?

[krytonsheep]

You should switch to using Capistrano

[Numpty]

I am only just getting my head round Python, but here are my thoughts:

a) what is Python error reporting like? Does it suffer from the same problem as other languages where the error often refers to a previous / subsequent line, or get a daft error because an error earlier was not handled by an exception handler?

b) When I copy 'n' paste that from your posting into Notepad, some of the indentation looks suspect. Double check your spaces & tabs.

c) Blank lines. When I run the code through the debugger step by step, it is stopping at lines 91 and 142 when I would not have expected it to. Do the blank lines within the procedurs/functions matter?

d) Can you rename the 'ftp' variable, even if it is to myftp or theftp. It is such a common term that it might be in use for something else somewhere else.

e) Change teardown to:

def teardown():
    global ars 
    global ftp
    
    print ('teardown 1')
    ftp.quit()
    print ('teardown 2')
    ars.Logoff()
    print ('teardown end')

just to be absolutely sure of where it is failing.

f) Don't bother closing the FTP connection! I.e., comment out the quit() and see what happens. (It'll time out after a few minutes anyway (probably!!)).

g) Can you trap an error that may occur to the ftp quit()?

h) Can you put something in immediately before the ftp.quit() that would test whether the ftp connection is still open? (A gut feeling...)

i) Instead of having teardown() called under the 'finally', put the following as inline code:

    ftp.quit()
    ars.Logoff()

j) Out of my depth here, but , is that 'try:' & 'finally:' necessary?

Is that of any use?

[AtW]

Looks like a cross between VB and Pascal.

[NickFitz]

i'm getting an error in teardown() of
"global name 'ftp' is not defined "
but I can't for the life of me work out why it isn't picking up the global ftp variable..

Adding import ftplib seemed to fix things for me - although I'd commented out much of your code, I was still using the FTP bits to open and then close a connection to localhost. Give it a try

[chef]

Adding import ftplib seemed to fix things for me - although I'd commented out much of your code, I was still using the FTP bits to open and then close a connection to localhost. Give it a try

Nick your a genius, I knew it was some idiotic/newbie/rookie mistake..

thank you

[Zippy]

Chef - I'm glad your problem got resolved (that NickFitz chappie is a bit good) but I'm slightly surprised by the lack of 'oo er missus' responses