From 6b5e2ebbd8e5fa0c4c581670ede0eb6e987591ad Mon Sep 17 00:00:00 2001
From: Patrick Canterino <patrick@patrick-canterino.de>
Date: Thu, 8 Mar 2018 21:24:36 +0100
Subject: [PATCH] Allow to rotate log files

---
 TODO.md      |  2 +-
 dsmonrot.ps1 | 28 +++++++++++++++++++++++++---
 2 files changed, 26 insertions(+), 4 deletions(-)

diff --git a/TODO.md b/TODO.md
index b725eeb..28bbea6 100644
--- a/TODO.md
+++ b/TODO.md
@@ -5,7 +5,7 @@
 - [x] ~~Check if the network drive already exists before connecting~~ ⇒ `New-PSDrive` throws an exception if drive is already connected
 - [x] Create a log file for the script
 - [x] Clean up the messages sent to the console or send them to the debug or error streams (e.g. `Write-Debug` or `Write-Error`)
-- [ ] Rotate log files
+- [x] Rotate log files
 - [x] Suppress output of some commands
 - [ ] Add some comments to the source code
 - [ ] Allow multiple backups for a day
\ No newline at end of file
diff --git a/dsmonrot.ps1 b/dsmonrot.ps1
index 95508a1..43f3fda 100644
--- a/dsmonrot.ps1
+++ b/dsmonrot.ps1
@@ -36,8 +36,9 @@
 # Every month a new log file is created
 [String]$logDir = "C:\Users\Patrick\Desktop\DSMonRot\log"
 # Keep log files for this amount of months (excluding the current month),
-# 0 for indefinite (currently not available)
-[Int32]$keepLogs = 1
+# 0 or less for indefinite (currently not available)
+# You should set this to at least the same as $keepMonths
+[Int32]$keepLogs = 2
 
 # Map network share to this drive letter, comment out if you don't want to use it
 [String]$smbDrive = "Z"
@@ -227,6 +228,26 @@ function Rotate-Backup {
 	}
 }
 
+function Rotate-Log {
+	if($keepLogs -le 0) {
+		return
+	}
+	
+	$keepLogsCount = $keepLogs
+	
+	Get-ChildItem $logDir -File | Where-Object {($_.Name -ne "$currMonth.log") -and ($_.Name -match "^\d{4,}-\d{2}\.log$")} | Sort-Object -Descending |
+	Foreach-Object {
+		if($keepLogsCount -ge 0) {
+			$keepLogsCount--
+		}
+		
+		if($keepLogsCount -eq -1) {
+			Write-Log "Deleting log file $($_.FullName)" -Path $logFile -Level Info
+			Remove-Item -Force $_.FullName
+		}
+	}
+}
+
 $dsAdditionalArgs = @("--UseVSS")
 
 $errorMessages = @()
@@ -239,7 +260,6 @@ $dsCommand = ""
 $currMonth = Get-Date -format "yyyy-MM"
 $currDay = Get-Date -format "yyyy-MM-dd"
 
-
 if(!(Test-Path $logDir)) {
 	try {
 		New-Item -ItemType directory -Path $logDir -ErrorAction Stop | Out-Null
@@ -398,6 +418,8 @@ if($errorMessages.Count -eq 0) {
 			$errorMessages +=  "Could not disconnect network drive $smbDrive`: $_.Exception.Message"
 		}
 	}
+	
+	Rotate-Log
 }
 
 if($emailOnError -and $errorMessages.Count -gt 0) {
-- 
2.34.1