Functions/GenXdev.FileSystem/ReadJsonWithRetry.ps1
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Part of PowerShell module : GenXdev.FileSystem Original cmdlet filename : ReadJsonWithRetry.ps1 Original author : René Vaessen / GenXdev Version : 1.298.2025 ################################################################################ MIT License Copyright 2021-2025 GenXdev Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions: The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software. THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. ################################################################################> ############################################################################### <# .SYNOPSIS Reads JSON file with retry logic and automatic lock cleanup. .DESCRIPTION Attempts to read a JSON file with retry logic to handle concurrent access. Implements automatic cleanup of stale lock files. Returns empty hashtable if file doesn't exist. .PARAMETER FilePath The path to the JSON file to read. .PARAMETER MaxRetries Maximum number of retry attempts. Defaults to 10. .PARAMETER RetryDelayMs Delay in milliseconds between retries. Defaults to 200. #> function ReadJsonWithRetry { [CmdletBinding()] param( [Parameter(Mandatory = $true)] [string]$FilePath, [Parameter(Mandatory = $false)] [int]$MaxRetries = 10, [Parameter(Mandatory = $false)] [int]$RetryDelayMs = 200 ) # return empty hashtable if file doesn't exist if (-not (Microsoft.PowerShell.Management\Test-Path -LiteralPath $FilePath)) { return @{} } # construct lock file path $lockFile = "${FilePath}.lock" # attempt to read with retries for ($attempt = 0; $attempt -lt $MaxRetries; $attempt++) { try { # clean up stale lock files older than 30 seconds if (Microsoft.PowerShell.Management\Test-Path -LiteralPath $lockFile) { $lockInfo = [System.IO.FileInfo]::new($lockFile) $ageSeconds = ([DateTime]::Now - $lockInfo.LastWriteTime).TotalSeconds if ($ageSeconds -gt 30) { Microsoft.PowerShell.Utility\Write-Verbose ` "Removing stale lock file: $lockFile (age: ${ageSeconds}s)" Microsoft.PowerShell.Management\Remove-Item ` -LiteralPath $lockFile ` -Force ` -ErrorAction SilentlyContinue } } # read and parse json file $content = Microsoft.PowerShell.Management\Get-Content ` -LiteralPath $FilePath ` -Raw ` -ErrorAction Stop if ([string]::IsNullOrWhiteSpace($content)) { return @{} } $data = $content | Microsoft.PowerShell.Utility\ConvertFrom-Json ` -AsHashtable ` -ErrorAction Stop return $data } catch { # log retry attempt Microsoft.PowerShell.Utility\Write-Verbose ` "Read attempt $($attempt + 1) failed: $($_.Exception.Message)" # wait before retry unless this is the last attempt if ($attempt -lt ($MaxRetries - 1)) { Microsoft.PowerShell.Utility\Start-Sleep ` -Milliseconds $RetryDelayMs } else { # final attempt failed, throw error throw "Failed to read JSON file after ${MaxRetries} attempts: $_" } } } } |