Added comments, especially for config

[psmysqlbackup.git] / psmysqlbackup.ps1

diff --git a/psmysqlbackup.ps1 b/psmysqlbackup.ps1
index cc422a6d3da48dd12e3db028e74c880faed8d710..e7b2f5fbfd43e416beeb9397a207656a7df4dbf2 100644 (file)
--- a/psmysqlbackup.ps1
+++ b/psmysqlbackup.ps1
@@ -1,25 +1,48 @@
+# PSMySQLBackup
+# PowerShell script for backing up MySQL / MariaDB databases on Windows 
+#
+# Author: Patrick Canterino <patrick@patrick-canterino.de>
+# WWW: https://www.patrick-canterino.de/
+#      https://github.com/pcanterino/psmysqlbackup
+# License: 2-Clause BSD License
+
 # Config
 
+# MySQL host
 $configMysqlHost = "localhost"
+# Port of MySQL host
 $configMysqlPort = 3306
+# MySQL user using to connect to MySQL
 $configMysqlUser = "backup"
+# Password for MySQL user
 $configMysqlPassword = "backup"
 
+# Path to MySQL CLI program
 $configMysqlCli = "C:\Program Files\MariaDB 10.5\bin\mysql.exe"
+# Path to mysqldump CLI program
 $configMysqldumpCli = "C:\Program Files\MariaDB 10.5\bin\mysqldump.exe"
 
+# Directory where to store the backups
 $configBackupDir = "backup"
+# Number of backups to keep, set to 0 to keep all backups
 $configRotate = 7
 
+# Databases to backup, leave empty to backup all databases
 $configDbBackup = @()
-$configDbExclusions = @("test")
+# If $configDbBackup is empty, don't backup the databases defined here
+$configDbExclude = @("test")
+# If $configDbBackup is empty, don't backup the databases matching these patterns
+$configDbExcludePattern = @()
 
 # End of config
 
-$defaultExclusions = @("information_schema", "performance_schema")
-
 function Get-Databases() {
     $databaseString = (& $configMysqlCli --host=$configMysqlHost --port=$configMysqlPort --user=$configMysqlUser --password=$configMysqlPassword --batch --skip-column-names -e "SHOW DATABASES;")
+    
+    if($LastExitCode -ne 0) {
+        throw "MySQL CLI exited with Exit code $LastExitCode"
+    }
+    
     $databases = $databaseString.split([Environment]::NewLine)
 
     return $databases
@@ -27,50 +50,101 @@ function Get-Databases() {
 
 function Create-Backup([String]$database, [String]$target) {
     & $configMysqldumpCli --host=$configMysqlHost --port=$configMysqlPort --user=$configMysqlUser --password=$configMysqlPassword --single-transaction --result-file=$target $database
+
+    if($LastExitCode -ne 0) {
+        throw "mysqldump exited with Exit code $LastExitCode"
+    }
 }
 
 function Rotate-Backups($backupDir) {
     if($configRotate -le 0) {
-               return
-       }
-       
-       $keepBackupsCount = $configRotate
-       
-       Get-ChildItem $backupDir -File | Where-Object {($_.Name -match "^backup-.+-\d{8,}-\d{6}\.sql$")} | Sort-Object -Descending |
-       Foreach-Object {
-               if($keepBackupsCount -ge 0) {
-                       $keepBackupsCount--
-               }
-               
-               if($keepBackupsCount -eq -1) {
-                       Write-Output "Deleting backup $($_.FullName)"
-                       Remove-Item -Force $_.FullName
-               }
-       }
+        return
+    }
+    
+    $keepBackupsCount = $configRotate
+
+    Get-ChildItem $backupDir -File | Where-Object {($_.Name -match "^backup-.+-\d{8,}-\d{6}\.sql$")} | Sort-Object -Descending |
+    Foreach-Object {
+        if($keepBackupsCount -ge 0) {
+            $keepBackupsCount--
+        }
+
+        if($keepBackupsCount -eq -1) {
+            Write-Output "Deleting backup $($_.FullName)"
+            Remove-Item -Force $_.FullName
+        }
+    }
 }
 
+$defaultDbExclude = @("information_schema", "performance_schema")
+
 $currDaytime = Get-Date -format "yyyyMMdd-HHmmss"
 
-$databases = Get-Databases | Where-Object {!($_ -in $defaultExclusions -or $_ -in $configDbExclusions)}
+# Get a list of all databases
+try {
+    $databases = Get-Databases | Where-Object {!($_ -in $defaultDbExclude)}
+}
+catch {
+    Write-Output "Failed to get list of databases"
+    Write-Output $_
+    exit 1
+}
+
+# Create a list of databases to backup
 
 $databasesToBackup = @()
 
 if($configDbBackup -and $configDbBackup.count -gt 0) {
-    $databasesToBackup = $configDbBackup
+    foreach($cDb in $configDbBackup) {
+        if($cDb -in $databases) {
+            $databasesToBackup += $cDb
+        }
+        else {
+            Write-Warning "Not backing up database $cDb, because it does not exist"
+        }
+    }
 }
 else {
-    $databasesToBackup = $databases
+    :excludeOuter
+    foreach($rDb in $databases) {
+        if($rDb -in $configDbExclude) {
+            continue;
+        }
+
+        foreach($cPattern in $configDbExcludePattern) {
+            if($rDb -match $cPattern) {
+                continue excludeOuter;
+            }
+        }
+
+        $databasesToBackup += $rDb
+    }
 }
 
+# Iterate over the list of databases and back them up and rotate the backups
 foreach($d in $databasesToBackup) {
     $databaseBackupDir = Join-Path -Path $configBackupDir -ChildPath $d
 
     if(!(Test-Path $databaseBackupDir)) {
-        New-Item -ItemType directory -Path $databaseBackupDir -ErrorAction Stop | Out-Null
+        try {
+            New-Item -ItemType directory -Path "$databaseBackupDir" -ErrorAction Stop | Out-Null
+        }
+        catch {
+            Write-Output "Failed to create directory $databaseBackupDir"
+            Write-Output $_
+            exit 1
+        }
     }
 
     $databaseBackupFile = Join-Path -Path $databaseBackupDir -ChildPath "backup-$d-$currDaytime.sql"
     Write-Output "Backing up $d to $databaseBackupFile..."
-    Create-Backup $d $databaseBackupFile
-    Rotate-Backups $databaseBackupDir
+    
+    try {
+        Create-Backup $d $databaseBackupFile
+        Rotate-Backups $databaseBackupDir
+    }
+    catch {
+        Write-Output "Could not backup database $d to $databaseBackupFile"
+        Write-Output $_
+    }
 }
\ No newline at end of file