Advanced Windows PowerShell Scripting Video Training

Advanced Windows PowerShell Scripting Video Training
Advanced Windows PowerShell Scripting Video Training

Thursday, June 20, 2013

Using Text Based Logs with Windows PowerShell (7 of 8)


Day 7: Creating an object template
 
Yesterday we extracted a dynamic list of property names from our log file.  Today we will complete step 3: Create an object that contains all possible property names.
The object that we are creating is going to contain all of our properties with values set to $Null.  That way we will have a template without any restrictions on the data type that the properties will hold.
    Function New-EmptyObject
    {
    Param ($PropList)
    # Creates an empty object to be used for each instance of the final
    # object. This ensures a consistent set of members for the object.
       
        $Obj = New-Object -TypeName psobject
      
        # Change the type name.
        $Obj.pstypenames.insert(0,'Custom.LogObject')
      
        ForEach ($P in $Proplist.Prop)
        {
            $Obj | Add-Member -NotePropertyName "$($P)" `
                              -NotePropertyValue $Null
        } # End: ForEach ($P in $Proplist.Prop)
     
        # Return the object to the calling statement.
        Write-Output $Obj
    } # End Function New-EmptyObject
 
Here we are feeding the function New-EmptyObject our $Proplist object.  The function creates an empty object called $Obj and then changes the object type from System.Management.Automation.PSCustomObject  to Custom.LogObject.  Custome.LogObject is our own, unique object type. Next each property from the $PropList is added as a property of the object with a value set to $Null.  Once this is completed, the object is returned and stored as $EmptyObject.
 
Here is the code:
 
Function Import-MyLog2
{
    # -----------------------------------------------------------------------
    Function Get-Log
    {
    # Reads the log file into memory.  Will display an error if the
    # file cannot be found.
 
        Try
        {
            Get-Content -path "\\Server1\Log\Data2.txt" `
                        -ErrorAction Stop |
            Write-Output
        }
        Catch
        {
            Write-Error "The data file is not present"
            BREAK
        }
    } # End: Function Get-Log
    # -----------------------------------------------------------------------
    Function Get-RecordIndex
    {
    Param ($Log)
    # Determines the index number of where each record starts and ends.
    # Returns an object with the start and end index number of
    # each record.
 
        # Array to hold all of the objects.
        $Object = @()
       
        # Find the start of each record.
        For($X=0;$X -lt $Log.Count; $X++)
        {
            If($Log[$X] -like "Server Blade #* Information:")
            {
 
                $Obj = New-Object -TypeName PSObject
                $Obj | Add-Member -NotePropertyName "Start" `
                                  -NotePropertyValue $X
                $Obj | Add-Member -NotePropertyName "End" `
                                  -NotePropertyValue $Null
                $Object += $Obj
            }
        } # End: For($X=0;$X -lt $Log.Count; $X++)
 
        # Derive the end of each record.
        For ($X = 0; $X -lt $Object.Count - 1; $X++)
        {
            $Object[$X].End = $Object[$X+1].Start -1
        } # End: For ($X = 0; $X -lt $Object.Count; $X++)
 
        # Add the final End value as the end of the log file.
        $Object[$Object.count-1].End = $Log.count
 
        # Return the object to the calling statement.
        Write-Output $Object
       
    } # End: Function Get-RecordIndex
    # -----------------------------------------------------------------------
    Function Format-PropertyName
    {
    Param ($Name)
    # Used to get the proper name format for the list of properties and also
    # While creating the actual data for the final objects.
 
        $Value = $Name.Trim()
        $Pos = $Value.IndexOf(":")
        Write-Output $Value.Substring(0,$Pos).Replace(" ","")
               
    } # End: Function Format-PropertyName
    # -----------------------------------------------------------------------
    Function Get-PropertyList
    {
    Param($RecordIndex, $Log)
    # To help build a more flexible object, we need to identify possible
    # property names.  This function will cycle through each record and use
    # a rule to identify the name of a property.  Our rule is any string
    # other than the string that starts the record that starts with blank
    # characters, has text, and the it will end at the first ":".  All spaces
    # in the property names will also be removed.
       
        # Array to hold all of the objects.
        $Object = @()
 
        ForEach ($R in $RecordIndex)
        {
            For ($X=$R.Start+1;$X -lt $R.End;$X++)
            {
 
                # Examine only lines from the record that are not blank.
                If (($Log[$X].length -gt 0) -and ($Log[$X] -like "*:*"))
                {
                    $Obj = New-Object -TypeName PSObject
                    $Obj | Add-Member -MemberType NoteProperty `
                                      -Name "Prop" `
                                      -Value (Format-PropertyName -Name $Log[$X])
                   $Object += $Obj                
                }
            } # End: For ($X=$R.Start;$X -lt $R.End;$X++)
        } # End: ForEach ($R in $RecordIndex)
 
        # Add the "Slot" property to record the slot number.
        $Obj = New-Object -TypeName PSObject
        $Obj | Add-Member -MemberType NoteProperty `
                            -Name "Prop" `
                            -Value "Slot"
        $Object += $Obj
        # Filter the list of protential properties to make sure that they
        # are all unique.
        $Object = $Object | Select-Object -Property Prop -Unique
 
        # Return the object to the calling statement.
        Write-Output $Object
 
    } # End: Function Get-PropertyList
    # -----------------------------------------------------------------------
    Function Get-Record
    {
    Param ($Log,$RecordIndex)
       
        # Array to hold all of the objects.
        $Object = @()
 
        ForEach($R in $RecordIndex)
        {
            $Obj = New-Object -TypeName PSObject
            $String = $Null
            For($X=$R.Start;$X -lt $R.End; $X++)
            {
                $String += $Log[$X]
            }
            $Object += $String  
        }
       
        # Return the object to the calling statement.
        Write-Output $Object
 
    } # End: Function Get-Record
    # -----------------------------------------------------------------------
    Function New-EmptyObject
    {
    Param ($PropList)
    # Creates an empty object to be used for each instance of the final
    # object. This ensures a consistent set of members for the object.
       
        $Obj = New-Object -TypeName psobject
      
        # Change the type name.
        $Obj.pstypenames.insert(0,'Custom.LogObject')
      
        ForEach ($P in $Proplist.Prop)
        {
            $Obj | Add-Member -NotePropertyName "$($P)" `
                              -NotePropertyValue $Null
        } # End: ForEach ($P in $Proplist.Prop)
     
        # Return the object to the calling statement.
        Write-Output $Obj
    } # End Function New-EmptyObject
    # -----------------------------------------------------------------------
    # Load the log into memory
    $Log = Get-Log
 
    # Extract the records
    $RecordIndex = Get-RecordIndex -Log $Log
 
    # Extract the propertyl list.
    $PropList = Get-PropertyList -RecordIndex $RecordIndex -Log $Log
 
    # Create an empty object to use as our template using our $PropList.
    $EmptyObj = New-EmptyObject -PropList $PropList
    $EmptyObj # This line will be removed.  It shows our current progress.
 
} #End: Function Import-MyLog1
 
Here is our output:
 
ServerBladeType                  :
Type                             :
Manufacturer                     :
ProductName                      :
PartNumber                       :
SystemBoardSparePartNumber       :
SerialNumber                     :
UUID                             :
ServerName                       :
AssetTag                         :
ROMVersion                       :
CPU1                             :
CPU2                             :
Memory                           :
NIC1                             :
NIC2                             :
NIC3                             :
NIC4                             :
iSCSI1                           :
iSCSI2                           :
Mezzanine2                       :
Port1                            :
Port2                            :
ManagementProcessorInformation   :
Name                             :
FirmwareVersion                  :
IPAddress                        :
MACAddress                       :
PowerManagementControllerVersion :
FLBAdapter1                      :
EthernetFlexNIC(NIC1)LOM1        :
EthernetFlexNIC(NIC3)LOM1        :
EthernetFlexNIC(NIC5)LOM1        :
EthernetFlexNIC(NIC7)LOM1        :
EthernetFlexNIC(NIC2)LOM1        :
EthernetFlexNIC(NIC4)LOM1        :
EthernetFlexNIC(NIC6)LOM1        :
EthernetFlexNIC(NIC8)LOM1        :
Slot                             :  
 
 
Tomorrow we will finish up and tie everything together.

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