CheckFlag.ps1

#Requires -Version 3.0

<#
.SYNOPSIS

This script checkes existence(or non-existence)  of a flag file, and create(or delete) the flag file.
CommonFunctions.ps1 is required.



.DESCRIPTION

This script checkes existence(or non-existence)  of a flag file, and create(or delete) the flag file.
If status of existence(or non-existence) is true, exit with normal return code.
If status of existence(or non-existence) is false, exit with warning return code.

If specify -PostAction option, the script create(or delete) the flag file.

Output log to [Windows Event Log] or [Console] or [Text Log] and specify to suppress or to output individually. 


Sample Path

.\CheckFlag.ps1
.\CommonFunctions.ps1
..\Lock\BackUp.Flg



.EXAMPLE

.\CheckFlag -FlagFolder ..\Lock -FlagFile BackUp.Flg

Check BackUp.Flg file in the ..\Lock folder.
If the file exists, the script exit with warning return code.
If the file dose not exist, the script exit with normal return code.

For backward compatibility, run without specification -Status option, -Status will be 'NoExist' by default.


.EXAMPLE

.\CheckFlag -FlagFolder ..\Lock -FlagFile BackUp.Flg -Status Exist -PostAction Delete

Check BackUp.Flg file in the ..\Lock folder.
If the file dose not exist, the script exit with warning return code.
If the file exists, the script delete the flag file.

If success to delete, the script exit with normal return code.
If fail to delte, the script exit with error return code.



.PARAMETER FlagFolder

Specify the folder to check existence of flag file.
Can specify relative, absolute or UNC path format.
Relative path format must be starting with 'dot.'
Wild cards are not accepted shch as asterisk* question? bracket[]
If the path contains bracket[] , specify path literally and do not escape.


.PARAMETER FlagFile

Specify name of the flag file.


.PARAMETER Status

Specify [Exist]ence or [NoExist]ence of the flag file.
[NoExist] is by default.


.PARAMETER PostAction

Specify action to [Delete] or [Create] a flag file after checking.



.PARAMETER CommonConfigPath

Specify common configuration file path in relative path format.
Only this parameter, you can specify the path with only relative path format.
With this parameter, you can specify same event id for utility scripts with common config file.
If you want to cancel using common config file specified in Param section of the script, specify this argument with NULL or empty string.


.PARAMETER Log2EventLog

Specify if you want to output log to Windows Event Log.
[$TRUE] is default.


.PARAMETER NoLog2EventLog

Specify if you want to suppress log to Windows Event Log.
Specification overrides -Log2EventLog


.PARAMETER ProviderName

Specify provider name of Windows Event Log.
[Infra] is default.


.PARAMETER EventLogLogName

Specify log name of Windows Event Log.
[Application] is default.


.PARAMETER Log2Console

Specify if you want to output log to PowerShell console.
[$TRUE] is default.


.PARAMETER NoLog2Console

Specify if you want to suppress log to PowerShell console.
Specification overrides -Log2Console


.PARAMETER Log2File

Specify if you want to output log to text log.
[$FALSE] is default.


.PARAMETER NoLog2File

Specify if you want to suppress log to PowerShell console.
Specification overrides -Log2File


.PARAMETER LogPath

Specify the path of text log file.
Can specify relative, absolute or UNC path format.
Relative path format must be starting with 'dot.'
Wild cards are not accepted shch as asterisk* question? bracket[]
If the path contains bracket[] , specify path literally and do not escape.
[$NULL] is default.

If the log file dose not exist, the script makes a new file.
If the log file exists, the script writes log additionally.


.PARAMETER LogDateFormat

Specicy time stamp format in the text log.
[yyyy-MM-dd-HH:mm:ss] is default.


.PARAMETER LogFileEncode

Specify the character encode in the log file.
[Default] is default and it works as ShiftJIS.


.PARAMETER NormalReturnCode

Specify Normal Return code.
[0] is default.
Must specify NormalReturnCode < WarningReturnCode < ErrorReturnCode < InternalErrorReturnCode


.PARAMETER WarningReturnCode

Specify Warning Return code.
[1] is default.
Must specify NormalReturnCode < WarningReturnCode < ErrorReturnCode < InternalErrorReturnCode


.PARAMETER ErrorReturnCode

Specify Error Return code.
[8] is default.
Must specify NormalReturnCode < WarningReturnCode < ErrorReturnCode < InternalErrorReturnCode


.PARAMETER InternalErrorReturnCode

Specify Internal Error Return code.
[16] is default.
Must specify NormalReturnCode < WarningReturnCode < ErrorReturnCode < InternalErrorReturnCode


.PARAMETER InfoEventID

Specify information event id in the log.
[1] is default.


.PARAMETER InfoLoopStartEventID

Specify start loop event id in the log.
[2] is default.


.PARAMETER InfoLoopEndEventID

Specify end loop event id in the log.
[3] is default.


.PARAMETER StartEventID

Specify start script id in the log.
[8] is default.


.PARAMETER EndEventID

Specify end script event id in the log.
[9] is default.


.PARAMETER WarningEventID

Specify Warning event id in the log.
[10] is default.


.PARAMETER SuccessEventID

Specify Successfully complete event id in the log.
[73] is default.


.PARAMETER InternalErrorEventID

Specify Internal Error event id in the log.
[99] is default.


.PARAMETER ErrorEventID

Specify Error event id in the log.
[100] is default.


.PARAMETER ErrorAsWarning

Specfy if you want to return WARNING exit code when the script terminate with an Error.


.PARAMETER WarningAsNormal

Specify if you want to return NORMAL exit code when the script terminate with a Warning.


.PARAMETER ExecutableUser

Specify the users who are allowed to execute the script in regular expression.
[.*] is default and all users are allowed to execute.
Parameter must be quoted with single quote'
Escape the back slash in the separeter of a domain name.
example [domain\\.*]



.NOTES

Copyright 2020 Masayuki Sudo

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.



.LINK

https://github.com/7k2mpa/FileMaintenace



.OUTPUTS

System.Int. Return Code.

#>

#!!! start of definition !!!#
[CmdletBinding(SupportsShouldProcess=$true,ConfirmImpact="High")]
Param(

[String][parameter(position = 0, mandatory, ValueFromPipeline, ValueFromPipelineByPropertyName, HelpMessage = 'Specify the folder of a flag file placed.(ex. D:\lock) Get-Help CheckFlag.ps1')]
[ValidatePattern('^(\\\\|\.+\\|[c-zC-Z]:\\)(?!.*(\/|:|\?|`"|<|>|\||\*)).*$')][Alias("Path","LiteralPath","FullName")]$FlagFolder ,

[String][parameter(position = 1, mandatory)][ValidateNotNullOrEmpty()][ValidatePattern ('^(?!.*(\/|:|\?|`"|<|>|\||\*|\\).*$)')][Alias("FlagFileName")]$FlagFile ,
[String][parameter(position = 2)][ValidateSet("Exist","NoExist")]$Status = 'NoExist' ,
[String][parameter(position = 3)][ValidateSet("Create","Delete")]$PostAction ,



#[String][ValidatePattern('^(|\0|(\.+\\)(?!.*(\/|:|\?|`"|<|>|\||\*))).*$')]$CommonConfigPath = '.\CommonConfig.ps1' , #MUST specify with relative path format
[String][ValidatePattern('^(|\0|(\.+\\)(?!.*(\/|:|\?|`"|<|>|\||\*))).*$')]$CommonConfigPath = $NULL ,


[Boolean]$Log2EventLog = $TRUE ,
[Switch]$NoLog2EventLog ,
[String][ValidateNotNullOrEmpty()]$ProviderName = 'Infra' ,
[String][ValidateSet("Application")]$EventLogLogName = 'Application' ,

[Boolean]$Log2Console = $TRUE ,
[Switch]$NoLog2Console ,

[Boolean]$Log2File = $FALSE ,
[Switch]$NoLog2File ,

[String][ValidatePattern('^(\\\\|\.+\\|[c-zC-Z]:\\)(?!.*(\/|:|\?|`"|<|>|\||\*)).*$')]$LogPath ,

[String][ValidateNotNullOrEmpty()]$LogDateFormat = 'yyyy-MM-dd-HH:mm:ss' ,
[String][ValidateSet("Default", "UTF8" , "UTF7" , "UTF32" , "Unicode")]$LogFileEncode = 'Default' , #Default ShiftJIS


[Int][ValidateRange(0,2147483647)]$NormalReturnCode        =  0 ,
[Int][ValidateRange(0,2147483647)]$WarningReturnCode       =  1 ,
[Int][ValidateRange(0,2147483647)]$ErrorReturnCode         =  8 ,
[Int][ValidateRange(0,2147483647)]$InternalErrorReturnCode = 16 ,

[Int][ValidateRange(1,65535)]$InfoEventID          =   1 ,
[Int][ValidateRange(1,65535)]$InfoLoopStartEventID =   2 ,
[Int][ValidateRange(1,65535)]$InfoLoopEndEventID   =   3 ,
[int][ValidateRange(1,65535)]$StartEventID         =   8 ,
[int][ValidateRange(1,65535)]$EndEventID           =   9 ,
[Int][ValidateRange(1,65535)]$WarningEventID       =  10 ,
[Int][ValidateRange(1,65535)]$SuccessEventID       =  73 ,
[Int][ValidateRange(1,65535)]$InternalErrorEventID =  99 ,
[Int][ValidateRange(1,65535)]$ErrorEventID         = 100 ,

[Switch]$ErrorAsWarning ,
[Switch]$WarningAsNormal ,

[Regex]$ExecutableUser = '.*'

)

################# CommonFunctions.ps1 Load  #######################
# If you want to place CommonFunctions.ps1 in differnt path, modify

Try {
    ."$PSScriptRoot\CommonFunctions.ps1"

    IF ($LASTEXITCODE -eq 99) {
        Exit 1
    }
}
Catch [Exception] {
    Write-Error "Fail to load CommonFunctions.ps1 Please verify existence of CommonFunctions.ps1 in the same folder."
    Exit 1
}

#!!! end of definition !!!


################# functions  #######################

function Initialize {

$ShellName = $PSCommandPath | Split-Path -Leaf

<#
PreInitialization for basic logging functions
Already egistered Event Source in Windows Event Log?
Log File output path
Validate Return Codes
Validate Execution user
Output Script Starting messages
#>
. Invoke-PreInitialize


#If passed PreInitilization, validate only business logics.


#Validate parameters


#Validate Flag Folder

$FlagFolder = $FlagFolder |
                ConvertTo-AbsolutePath -ObjectName '-FlagFolder' |
                Test-PathEx -Type Container -Name '-FlagFolder' -IfFalseFinalize -PassThrough


#Validate Flag Filename

    IF ($FlagFile -match '(\\|\/|:|\?|`"|<|>|\||\*)') {
    
        Write-Log -EventType Error -EventID $ErrorEventID -EventMessage "The path -FlagFile contains some characters that can not be used by NTFS"
        Finalize $ErrorReturnCode
        }

#Check invalid combination -Status and -PostAction

    IF (($Status -eq 'Exist' -and $PostAction -eq 'Create') -or ($Status -eq 'NoExist' -and $PostAction -eq 'Delete')) {

        Write-Log -EventType Error -EventID $ErrorEventID -EventMessage "Must not specify -Status [$($Status)] and -PostAction [$($PostAction)] in the same time."
        Finalize $ErrorReturnCode        
        }


#output starting messages

Write-Log -EventID $InfoEventID -EventType Information -EventMessage "All parameters are valid"

Write-Log -EventID $InfoEventID -EventType Information -EventMessage "Starting to check existence of the flag file [$($FlagFile)]"

}


function Finalize {

Param(
[parameter(position = 0, mandatory)][int]$ReturnCode
)

 Invoke-PostFinalize $ReturnCode

}


#####################  main  ######################

$DatumPath = $PSScriptRoot

$Version = "3.0.0"


#initialize, validate parameters, output starting message

. Initialize


[String]$flagValue = $ShellName + " " + (Get-Date).ToString($LogDateFormat)
[String]$flagPath = $FlagFolder | Join-Path -ChildPath $FlagFile


Switch -Regex ($Status) {

    '^NoExist$' {

        IF (-not($flagPath | Test-PathEx -Type Leaf -Name 'Flag file') -and -not($flagPath | Test-PathEx -Type Container -Name 'Same name folder')) {

            Write-Log -EventID $InfoEventID -EventType Information -EventMessage "Flag file [$($flagPath)] dose not exist and terminates as NORMAL." 

            } else {
            Write-Log -EventID $WarningEventID -EventType Warning -EventMessage "Flag file [$($flagPath)] exists already and terminates as WARNING."
            Finalize $WarningReturnCode    
            }
        }

    '^Exist$' {
    
        IF ($flagPath | Test-PathEx -Type Leaf -Name 'Flag file') {

            Write-Log -EventID $InfoEventID -EventType Information -EventMessage "Flag file [$($flagPath)] exists and terminates as NORMAL."    

            } else {
            Write-Log -EventID $WarningEventID -EventType Warning -EventMessage "Flag file [$($flagPath)] is deleted already and terminates as WARNING."
            Finalize $WarningReturnCode
            }        
        }

    Default {
            
        Write-Log -EventID $InternalErrorEventID -EventType Error -EventMessage "Internal Error. Switch Status exception has occurred. "
        Finalize $InternalErrorReturnCode    
        }
}


Switch -Regex ($PostAction) {

    '^$' {
            Break
            }


    'Create' {

            Write-Log -EventID $InfoEventID -EventType Information -EventMessage "Specified -PostAction [$($PostAction)] option, thus $PostAction a flag file."        
            Invoke-Action -ActionType MakeNewFileWithValue -ActionFrom $flagPath -ActionError $flagPath -FileValue $flagValue
            Write-Log -EventID $SuccessEventID -EventType Success -EventMessage "Successfully completed to create the flag file [$($flagPath)]"
            }


    'Delete' {
 
            Write-Log -EventID $InfoEventID -EventType Information -EventMessage "Specified -PostAction [$($PostAction)] option, thus $PostAction a flag file."             
            Invoke-Action -ActionType Delete -ActionFrom $flagPath -ActionError $flagPath
            Write-Log -EventID $SuccessEventID -EventType Success -EventMessage "Successfully completed to delete the flag file [$($flagPath)]"
            }

    Default {

            Write-Log -EventID $InternalErrorEventID -EventType Error -EventMessage "Internal Error. Switch PostAction exception has occurred. "
            Finalize $InternalErrorReturnCode    
            }
}


Finalize -ReturnCode $NormalReturnCode