Write a correlation-aware JSON operation log

Script 1 min read Windows PowerShell 5.1 and PowerShell 7

Documentation: Microsoft Learn

Written and tested by Dhrub Bharali · Updated 02 October 2026

Each line is a complete JSON object with an ISO-8601 UTC timestamp and one correlation ID.

The script

1PS> $correlationId = [guid]::NewGuid().Guid

2PS> $log = '.\operation.jsonl'

3PS> function Add-OperationLog {

4PS> [CmdletBinding()]

5PS> param([string]$Level, [string]$Message, [hashtable]$Data = @{})

6PS> [pscustomobject]@{ Timestamp = (Get-Date).ToUniversalTime().ToString('o');CorrelationId = $correlationId;Level = $Level;Message = $Message;Data = $Data } |

7PS> ConvertTo-Json -Compress -Depth 6 | Add-Content -LiteralPath $log -Encoding utf8 }

8PS> Add-OperationLog -Level Information -Message 'Inventory started' -Data @{ Computer = $env:COMPUTERNAME }

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$correlationId = [guid]::NewGuid().Guid
$log = '.\operation.jsonl'
function Add-OperationLog {
  [CmdletBinding()]
  param([string]$Level, [string]$Message, [hashtable]$Data = @{})
  [pscustomobject]@{ Timestamp = (Get-Date).ToUniversalTime().ToString('o');CorrelationId = $correlationId;Level = $Level;Message = $Message;Data = $Data } |
  ConvertTo-Json -Compress -Depth 6 | Add-Content -LiteralPath $log -Encoding utf8 }
Add-OperationLog -Level Information -Message 'Inventory started' -Data @{ Computer = $env:COMPUTERNAME }

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Show reference output

1 {"Timestamp":"2026-09-10T12:00:00Z","CorrelationId":"11111111-2222-3333-4444-555555555555","Level":"Information","Message":"Operation completed","Data":{"Operation":"Inventory"}}

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$correlationId = [guid]::NewGuid().Guid
$log = '.\operation.jsonl'
function Add-OperationLog {
  [CmdletBinding()]
  param([string]$Level, [string]$Message, [hashtable]$Data = @{})
  [pscustomobject]@{ Timestamp = (Get-Date).ToUniversalTime().ToString('o');CorrelationId = $correlationId;Level = $Level;Message = $Message;Data = $Data } |
  ConvertTo-Json -Compress -Depth 6 | Add-Content -LiteralPath $log -Encoding utf8 }
Add-OperationLog -Level Information -Message 'Inventory started' -Data @{ Computer = $env:COMPUTERNAME }

Stage 1$correlationIdPositional values or no named parameters

How it works

Each line is a complete JSON object with an ISO-8601 UTC timestamp and one correlation ID. JSON Lines keeps appends cheap and lets a collector process records one at a time. The Data field preserves task-specific context without changing the top-level schema.

Adapting it

Add operation name, script version and duration when those are useful across runs. Send the same object to your logging API instead of Add-Content when a central collector exists.

Primary documentation

ConvertTo-Json reference

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The script

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How it works

Adapting it

Primary documentation

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