PsLogMessage.psm1
function ConvertTo-DnsFqdn { # Output the results of a DNS lookup to the default DNS server for the specified # Wrapper for [System.Net.Dns]::GetHostByName([string]$ComputerName) param ( [string]$ComputerName, <# Hostname of the computer running this function. Can be provided as a string to avoid calls to HOSTNAME.EXE #> [string]$ThisHostName = (HOSTNAME.EXE), # Username to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process) [string]$WhoAmI = (whoami.EXE), # Dictionary of log messages for Write-LogMsg (can be thread-safe if a synchronized hashtable is provided) [hashtable]$LogMsgCache = $Global:LogMessages ) $LogParams = @{ ThisHostname = $ThisHostname Type = 'Debug' LogMsgCache = $LogMsgCache WhoAmI = $WhoAmI } Write-LogMsg @LogParams -Text "[System.Net.Dns]::GetHostByName('$ComputerName')" [System.Net.Dns]::GetHostByName($ComputerName).HostName # -replace "^$ThisHostname", "$ThisHostname" #replace does not appear to be needed, capitalization is correct from GetHostByName() } function Get-CurrentHostName { # Future function to universally retrieve hostname using various methods (in order of preference): # hostname.exe # $env:hostname # CIM # other? } function Get-CurrentWhoAmI { # Output the results of whoami.exe after editing them to correct capitalization # whoami.exe returns lowercase but we want to honor the correct capitalization # Correct capitalization is returned from $ENV:USERNAME param ( <# Hostname of the computer running this function. Can be provided as a string to avoid calls to HOSTNAME.EXE #> [string]$ThisHostName = (HOSTNAME.EXE), # Username to record in log messages (can be passed to Write-LogMsg as a parameter to avoid calling an external process) [string]$WhoAmI = (whoami.EXE), # Dictionary of log messages for Write-LogMsg (can be thread-safe if a synchronized hashtable is provided) [hashtable]$LogMsgCache = $Global:LogMessages ) $WhoAmI -replace "^$ThisHostname\\", "$ThisHostname\" -replace "$ENV:USERNAME", $ENV:USERNAME if (-not $PSBoundParameters.ContainsKey('WhoAmI')) { $LogParams = @{ ThisHostname = $ThisHostname Type = 'Debug' LogMsgCache = $LogMsgCache WhoAmI = $WhoAmI } # Technically this exe has already been run, but it is advantageous to offer it as a parameter # Also, this way the log will use the correct capitalization Write-LogMsg @LogParams -Text "& whoami.exe" } } function New-DatedSubfolder { # Creates a folder structure with a folder for each year and month # Then it creates one timestamped folder inside the appropriate month # This folder is intended to be used to store output from a single execution of a script param ( [parameter(Mandatory)] [string]$Root, # A suffix to append to the folder name [string]$Suffix ) $Year = Get-Date -Format 'yyyy' $Month = Get-Date -Format 'MM' $Timestamp = (Get-Date -Format s) -replace ':', '-' $NewDir = "$Root\$Year\$Month\$Timestamp$Suffix" $null = New-Item -ItemType Directory -Path $NewDir -ErrorAction SilentlyContinue Write-Output $NewDir } function Write-LogMsg { <# .SYNOPSIS Prepend a prefix to a log message, write the message to an output stream, and write the message to a text file. Writes a message to a log file and/or PowerShell output stream .DESCRIPTION Prepends the log message with: a current timestamp the current hostname the current username the current command (function or file name) the current location (line number in the code) Tab-delimits these fields for a compromise between readability and parseability Adds the log message to either: * a hashtable (which can be thread-safe) using the timestamp as the key, which was passed to the $LogMsgCache parameter * a Global:$LogMessages variable which was created by the PsLogMessage module during import Optionally writes the message to a log file Optionally writes the message to a PowerShell output stream .INPUTS [System.String]$Text parameter .OUTPUTS [System.String] Resulting log line, returned if the -PassThru or -Type Output parameters were used #> [OutputType([System.String])] [CmdletBinding()] param( # Message to log [Parameter(Position = 0, ValueFromPipeline)] [string]$Text, # Output stream to send the message to [ValidateSet('Silent', 'Quiet', 'Success', 'Debug', 'Verbose', 'Output', 'Host', 'Warning', 'Error', 'Information', $null)] [string]$Type = 'Information', # Add a prefix to the message including the date, hostname, current user, and info about the current call stack [bool]$AddPrefix = $true, # Text file to append the log message to [string]$LogFile, # Output the message to the pipeline [bool]$PassThru = $false, # Hostname to use in the log messages and/or output object [string]$ThisHostname = (HOSTNAME.EXE), # Hostname to use in the log messages and/or output object [string]$WhoAmI = (whoami.EXE), [hashtable]$LogMsgCache = $Global:LogMessages ) # This will ensure the message is not written to any PowerShell output streams or log files if ($Type -eq 'Silent') { return } $Timestamp = Get-Date -Format 'yyyy-MM-ddThh:mm:ss.ffff' $OutputToPipeline = $false $PSCallStack = Get-PSCallStack if ($null -ne $PSCallStack) { $Location = $PSCallStack[1].Location $Command = $PSCallStack[1].Command } else { $Location = $null $Command = $null } if ($AddPrefix) { # This method is faster than StringBuilder or the -join operator [string]$MessageToLog = "$Timestamp`t$ThisHostname`t$WhoAmI`t$Location`t$Command`t$($MyInvocation.ScriptLineNumber)`t$($Type)`t$($Text)" } else { [string]$MessageToLog = $Text } Switch ($Type) { # This will ensure the message is added to log files, but not written to any PowerShell output streams 'Quiet' {} # This one is made-up to correspond with the 'success' contextual class in Bootstrap. 'Success' { Write-Information "SUCCESS: $MessageToLog" } # These represent normal PowerShell output streams # The correct number of spaces should be added to maintain proper column alignment 'Debug' { Write-Debug " $MessageToLog" } 'Verbose' { Write-Verbose $MessageToLog } 'Host' { Write-Host "HOST: $MessageToLog" } 'Warning' { Write-Warning $MessageToLog } 'Error' { Write-Error $MessageToLog } 'Output' { $OutputToPipeline = $true } default { Write-Information "INFO: $MessageToLog" } } if ('' -ne $LogFile) { $MessageToLog | Out-File $LogFile -Append } if ($PassThru -or $OutputToPipeline) { $MessageToLog } # Add a GUID to the timestamp and use it as a unique key in the hashtable of log messages [string]$Guid = [guid]::NewGuid() [string]$Key = "$Timestamp$Guid" return $LogMsgCache[$Key] = [pscustomobject]@{ Timestamp = $Timestamp Hostname = $ThisHostname WhoAmI = $WhoAmI Location = $Location Command = $Command Line = $MyInvocation.ScriptLineNumber Type = $Type Text = $Text } } <# # Add any custom C# classes as usable (exported) types $CSharpFiles = Get-ChildItem -Path "$PSScriptRoot\*.cs" ForEach ($ThisFile in $CSharpFiles) { Add-Type -Path $ThisFile.FullName -ErrorAction Stop } #> Export-ModuleMember -Function @('ConvertTo-DnsFqdn','Get-CurrentHostname','Get-CurrentWhoAmI','New-DatedSubfolder','Write-LogMsg') #$Global:LogMessages = [system.collections.generic.list[pscustomobject]]::new() $Global:LogMessages = [hashtable]::Synchronized(@{}) |