How to pass string variable into search function?

Question

I am having issues passing a string variable into a search function.

Here is what I'm trying to accomplish:
I have a file full of values and I want to check the file to make sure a specific matching line exists before I proceed. I want to ensure that the line <endSW=UNIQUE-DNS-NAME-HERE<> exists if a valid <begSW=UNIQUE-DNS-NAME-HERE<> exists and is reachable.

Everything works fine until I call if searchForString(searchString,fileLoc): which always returns false. If I assign the variable 'searchString' a direct value and pass it it works, so I know it must be something with the way I'm combining the strings, but I can't seem to figure out what I'm doing wrong.

If I examine the data that 'searchForString' is using I see what seems to be valid values:

values in fileLines list:

['<begSW=UNIQUE-DNS-NAME-HERE<>', '    <begPortType=UNIQUE-PORT-HERE<>', '        <portNumbers=80,443,22<>', '    <endPortType=UNIQUE-PORT-HERE<>', '<endSW=UNIQUE-DNS-NAME-HERE<>']

value of searchVar:

<endSW=UNIQUE-DNS-NAME-HERE<>

An example of the entry in the file is:

<begSW=UNIQUE-DNS-NAME-HERE<>
    <begPortType=UNIQUE-PORT-HERE<>
        <portNumbers=80,443,22<>
    <endPortType=UNIQUE-PORT-HERE<>
<endSW=UNIQUE-DNS-NAME-HERE<>

Here is the code in question:

def searchForString(searchVar,readFile):
    with open(readFile) as findMe:
        fileLines = findMe.read().splitlines()
        print fileLines
        print searchVar
        if searchVar in fileLines:
            return True
        return False
    findMe.close()

fileLoc = '/dir/folder/file'
fileLoc.lstrip()
fileLoc.rstrip()
with open(fileLoc,'r') as switchFile:
    for line in switchFile:
        #declare all the vars we need
        lineDelimiter = '#'
        endLine = '<>\n'
        begSWLine= '<begSW='
        endSWLine = '<endSW='
        begPortType = '<begPortType='
        endPortType = '<endPortType='
        portNumList = '<portNumbers='
        #skip over commented lines -(REMOVE THIS)
        if line.startswith(lineDelimiter):
            pass
        #checks the file for a valid switch name
        #checks to see if the host is up and reachable
        #checks to see if there is a file input is valid
        if line.startswith(begSWLine):
            #extract switch name from file
            switchName = line[7:-3]
            #check to make sure switch is up
            if pingCheck(switchName):
                print 'Ping success. Host is reachable.'
                searchString = endSWLine+switchName+'<>'
                **#THIS PART IS SUCKING, WORKS WITH DIRECT STRING PASS
                #WONT WORK WITH A VARIABLE**
                if searchForString(searchString,fileLoc):
                    print 'found!'
                else:
                    print 'not found'   

Any advice or guidance would be extremely helpful.

Answer 1

Hard to tell without the file's contents, but I would try

switchName = line[7:-2]

So that would look like

>>> '<begSW=UNIQUE-DNS-NAME-HERE<>'[7:-2]
'UNIQUE-DNS-NAME-HERE'

Additionally, you could look into regex searches to make your cleanup more versatile.

import re
# re.findall(search_expression, string_to_search)   

>>> re.findall('\=(.+)(?:\<)', '<begSW=UNIQUE-DNS-NAME-HERE<>')[0]
'UNIQUE-DNS-NAME-HERE'

>>> e.findall('\=(.+)(?:\<)', '        <portNumbers=80,443,22<>')[0]
'80,443,22'

Answer 2

I found how to recursively iterate over XML tags in Python using ElementTree? and used the methods detailed to parse an XML file instead of using a TXT file.