Extract info from Logs

One of my projects used to update set of log files for each action and scheduled actions. Exceptions are logged in those log files. Log file size is maintained upto 5 MB. We are unable to get the proper logs, if scripts are running more than 15 minutes. Entire suite runs almost 75 hours continuously.

Many times, we were unable to re-look at the exceptions in the logs for particular test case failed time. I thought to develop a vbscript to capture the exceptions from log file for frequent intervals and then write into another text file. It can be used for manual testing too. Here I made two things. First is, script has to parse the log file for the given string. Second is, script should not update the log information, which is already available. I meant, the same information should not be added multiple times.

Code to take only unique info It returns the information as Array. Array size is determined in run-time.

 
'-------------------------------------------------------------------------
' Method    :   TrimArrayToExtract
' Author    :   T. Palani Selvam
' Purpose   :   Remove the array elements based on given info (sItemToCheck).
' Parameters:   arrInput - Array String, Contains logging message.
'  sItemToCheck - String, to check the element match. Last element in the text file
' Returns   :   String - Array. Returns remaining elements from the given array.
' Caller    :   - Nil
' Calls     :   - Nil
'-------------------------------------------------------------------------
Function TrimArrayToExtract (arrInput, sItemToCheck)
    Dim iArrItem
    Dim sTemp
    Dim arrOutput()
    
    iIndex=0
    If (IsNull(sItemToCheck) Or IsEmpty(sItemToCheck) Or (Trim(sItemToCheck)= "")) Then
     TrimArrayToExtract=arrInput
     Exit Function
    Else    
     If (IsArray(arrInput)) Then
        'If (Not (IsNull(arrInput) Or IsEmpty(arrInput)) And (UBound(arrInput)> 1)) Then
        If (Not (IsNull(arrInput) Or IsEmpty(arrInput) Or (UBound(arrInput)=0)) ) Then
         'WScript.Echo "ArrInput : " & arrInput
      For iArrItem=0 to UBound(arrInput)  ''-1
   ReDim Preserve arrOutput(iIndex)
   sTemp=arrInput(iArrItem)
   If (sTemp=sItemToCheck) Then
      iIndex=0
      Erase arrOutput
   Else
      arrOutput(iIndex)=sTemp
      iIndex=iIndex+1
   End If

      Next 
    End If
  End If
   End If
    
   TrimArrayToExtract=arrOutput
   
End Function

Code for Extracting the information from Log file It returns the information in Array.

 
'--------------------------------------
' Method    :   ExtractInfoFromLog
' Author    :   T. Palani Selvam
' Purpose   :   To extract the lines from a log file based on given info.
' Parameters:   sFileName - String, contains the log filename with full path.
'               sInfo2Extract - String, Info to search.
' Returns   :   Array of String
' Caller    :   - Nil
' Calls     :   - Nil
'--------------------------------------
Function ExtractInfoFromLog (sFileName, sInfo2Extract)

 Dim objFSO, objTextFile, sLine
 Dim iPos
 Dim arrExtract()
 Dim iLinesToDo, iArrIndex, iLimit
 
 Const ForReading=1
 Const NoOfLines=10

 
 iArrIndex=0
 iLinesToDo=0
 iLimit=1
 
 Set objFSO = CreateObject("Scripting.FileSystemObject")
 If  objFSO.FileExists(sFileName) Then

   Set objTextFile = objFSO.OpenTextFile(sFileName, ForReading) 

   Do while Not objTextFile.AtEndOfStream
  sLine = objTextFile.ReadLine        
  'Wscript.Echo sLine
  If (iLinesToDo > 0) Then
   arrExtract(iArrIndex)=sLine   
   iLinesToDo=iLinesToDo-1
   iArrIndex=iArrIndex+1
  Else
   
   iLinesToDo=0
   iPos=InStr(sLine,sInfo2Extract)
   'WScript.Echo("iPos  " & CStr(iPos))
   If (iPos>0) Then
    'WScript.Echo("Entered into If loop to extract from line: " & sLine)

    '' iLimit = UBound (arrExtract) + NoOfLines
    iLimit = iLimit + NoOfLines
    ReDim Preserve arrExtract(iLimit)

    arrExtract(iArrIndex)=sLine   
    iLinesToDo=NoOfLines-1 
    iArrIndex=iArrIndex+1

   Else
    iLinesToDo=0

   End If
  End If
  
   Loop

 End If

 objTextFile.Close

 Set objTextFile = Nothing 
 Set objFSO = Nothing 
 
 ExtractInfoFromLog=arrExtract
End Function

Note: Few user-defined functions might be used.