Get-NixLog.ps1
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function Get-NixLog { <# .Synopsis Gets log information from journalctl or syslog formatted logs. .Description Gets log via journalctl produced by the journald service which is standard on all distros that use systemd. If the -LogFilePath parameter is used then the command uses regex to parse in the Syslog format. Otherwise .Example # returns all logs unfiltered from journald Get-NigLog CURSOR : s=1032b59ef7f247819e0500ebe21424d3;i=19ac95;b=cab0af3b917244288fe2a15fc3b01 a42;m=1767c381e6c;t=5c65195d4a866;x=2e08686703b082cb REALTIME_TIMESTAMP : 1625428591945830 MONOTONIC_TIMESTAMP : 1608401821292 BOOT_ID : <someBootID> MACHINE_ID : <someGuid> HOSTNAME : ubuntu SELINUX_CONTEXT : unconfined SYSTEMD_SLICE : system.slice SYSLOG_FACILITY : 3 TRANSPORT : journal PRIORITY : 4 CODE_FILE : ../src/resolve/resolved-dns-transaction.c CODE_LINE : 1047 CODE_FUNC : dns_transaction_process_reply SYSLOG_IDENTIFIER : systemd-resolved MESSAGE : Server returned error NXDOMAIN, mitigating potential DNS violation DVE-2018-0001, retrying transaction with reduced feature level UDP. PID : 899 UID : 101 GID : 103 COMM : systemd-resolve EXE : /lib/systemd/systemd-resolved CMDLINE : /lib/systemd/systemd-resolved CAP_EFFECTIVE : 0 SYSTEMD_CGROUP : /system.slice/systemd-resolved.service SYSTEMD_UNIT : systemd-resolved.service SYSTEMD_INVOCATION_ID : <someSystemD_ID> SOURCE_REALTIME_TIMESTAMP : 1625428591945762 .Example # Returns logs from the /var/log/syslog in the following format Get-NixLog -LogFilePath /var/log/syslog DATE : Jun 20 19:56:14 HOSTNAME : ubuntu PROCESS : powershell PID : 16195 MESSAGE : {(7.1.3:1:80) [Perftrack_ConsoleStartupStart:PowershellConsoleStartup.WinStart.Informational] PowerShell console is starting up, } .Example # Uses native journalctl filtering to limit logs to a specifc time and priority # Like other PowerShell commands filtering on the cmdlet is faster than filtering later in the pipeline Get-NixLog -After "2021-06-21 00:00:00" -Priority err,warning | select -first 10 .Example # Group all logs in the current syslog file by minute Get-NixLog -LogFilePath '/var/log/syslog' | Group-Object {$_.date.minute} #> [OutputType([Nullable], [string])] [Cmdletbinding(DefaultParameterSetName='Journalctl')] param( # The path to the logfile read by. [Parameter(ValueFromPipelineByPropertyName,ParameterSetName='LogFile')] [Alias("Fullname")] [ValidateScript( { #Faster method for Resolve-Path $ExecutionContext.SessionState.Path.GetResolvedPSPathFromPSPath($PSItem) -as [bool] } )] [string] $LogFilePath, # A Time based filter for logs before a date. Example timestamp is "2020-04-08 17:12:00" # Could also be yesterday, today, tomorrow # [datetime]::now.ToString('s').Replace('T',' ') [Parameter(ParameterSetName='Journalctl',ValueFromPipelineByPropertyName)] [string] [alias('until')] $Before, # A Time based filter for logs after a date. Example timestamp is "2020-04-08 17:12:00" # Could also be yesterday, today, tomorrow # [datetime]::now.ToString('s').Replace('T',' ') [Parameter(ParameterSetName='Journalctl',ValueFromPipelineByPropertyName)] [string] [alias('since')] $After, # Explicitly require logs in UTC [Parameter(ParameterSetName='Journalctl',ValueFromPipelineByPropertyName)] [switch] $UTC, # Request only kernel logs like dmesg [Parameter(ParameterSetName='Journalctl',ValueFromPipelineByPropertyName)] [switch] [alias('dmesg')] $KernalOnly, # Offset number of the boot logs to look at. 0 is current boot, -1 is previous, etc. [Parameter(ParameterSetName='Journalctl',ValueFromPipelineByPropertyName)] [int] [alias('b')] $Boot, # Number of lines to show [Parameter(ParameterSetName='Journalctl',ValueFromPipelineByPropertyName)] [uint] [alias('n')] $LineNumber, # The specific syslog identifier you are looking at filtering. Can provided multiple identifiers [Parameter(ParameterSetName='Journalctl',ValueFromPipelineByPropertyName)] [string[]] $Identifier, # The specific Systemd unit you are looking at filtering. Can provided multiple units [Parameter(ParameterSetName='Journalctl',ValueFromPipelineByPropertyName)] [string[]] $Unit, # The priority of the logs you want to retrieve. # "emerg" (0), "alert" (1), "crit" (2), "err" (3), "warning" (4), "notice" (5), "info" (6), "debug" (7). [Parameter(ParameterSetName='Journalctl',ValueFromPipelineByPropertyName)] [string[]] $Priority ) begin{ # Contains patterns to identify the logging type # Name captures will be declared as variables # for example (?<hostname>\w+) will populate hostname $logPatterns = [ordered]@{ Syslog = '(?<date>^\w.+:\d{2})\s(?<hostname>[a-zA-Z0-9][-a-zA-Z0-9_]+)\s(?<process>.+?:)\s(?<message>.*)' } # Contains the script blocks to handle a given log type $logReaders = [ordered]@{ Syslog = { #Match a pid for the format [<number>] and assign it to the group process_pid $process_pid = if($process -match '(?<process_pid>(?<=\[)(?>.+\d)(?=\]))' ){$matches.process_pid -as [int]} else{$null} #Match a process until a [ or : $process_name = if($process -match '(?<process_name>^.+\w(?=\[|:))'){$matches.process_name} [PSCustomObject][ordered]@{ PsTypeName = "PowerNix.Log.Syslog" DATE = [datetime]::ParseExact($date, "MMM dd HH:mm:ss", [CultureInfo]::InvariantCulture) HOSTNAME = $hostname PROCESS = $process_name PID = $process_pid MESSAGE = $message } } } } process { if($LogFilePath) { $isfirstline = $true $logReader = '' $LogFileContent = Get-Content -Path $LogFilePath $LogFileContent | & { process { if($isfirstline) { $isfirstline = $false # look through each log file pattern foreach ($kv in $logPatterns.GetEnumerator()){ # if the pattern matches select the log type if( $PSItem -match $kv.Value ) { $logReader = $kv.Key break } } if (-not $logReader) { Write-Error -Message "Unable to parse log" -TargetObject $LogFilePath } } if (-not $logPatterns[$logReader] -or -not $logReaders[$logReader]){ return } foreach ($match in [regex]::Matches($PSItem, $logPatterns[$logReader]) ){ foreach ($group in $match.groups){ $ExecutionContext.SessionState.PSVariable.Set($group.name, $group.value) } & $logReaders[$logReader] } } } } else { # check that the system is using systemd if (-not (pidof systemd)) { Write-Error "Systemd not detected must use -LogFilePath" -ErrorId File.Missing return } $journalArgs = @('-r','-o','json' if($UTC){"--utc"} if($KernalOnly){"--dmesg"} if($Boot){"-b","$Boot"} if($LineNumber){"-n","$LineNumber"} if($Identifier){foreach($i in $Identifier){"-t","$i"}} if($Unit){foreach($u in $Unit){"-u","$u"}} if($Before){"-U","`"$Before`""} if($After){"-S","`"$After`""} if($Priority) { if ($Priority.Count -gt 1) { "-p","$($priority[0])..$($priority[-1])" } else { "-p","$Priority" } } )#end of the array # Invoking journalctl with arguements from parameters. $results = journalctl @journalArgs convertfrom-json -InputObject $results | & { process { $journalcltLogs = [Ordered]@{PSTypeName='PowerNix.Logs'} # create a dictionary to hold logs. foreach($v in $psitem.psobject.properties) { $name = $($v.name -replace '^_{1,2}') # Removing all leading underscores $value = $v.value $journalcltLogs[$name] = $value } [PSCustomObject]$journalcltLogs } } } } } |