PsLogger.psm1

<#
.SYNOPSIS
	Structured logging PowerShell module with JSONL formatted logfiles for OpenTelemetry.
#>

class Logger {
	[datetime]$Timestamp = (Get-Date)
	[ValidateRange(1, 24)]
	[int]$Level = 9
	[string]$Message = $null
	[hashtable]$Attributes

	hidden static [string] GetSeverity([int]$level) {
		switch ($level) {
			{$_ -in 1..4}   { return 'TRACE' }
			{$_ -in 5..8}   { return 'DEBUG' }
			{$_ -in 13..16} { return 'WARN' }
			{$_ -in 17..20} { return 'ERROR' }
			{$_ -in 21..24} { return 'FATAL' }
			default         { return 'INFO' }
		}

		return 'INFO'
	}

	[string]FormatLog() {
		return "[$(($this.Timestamp).ToString('o'))] [$(($this.Level).ToString())] $($this.Message)"
	}

	[string]FormatLogRecord() {
		$logEntry = @{
			timestamp       = $this.Timestamp.ToUniversalTime().ToString('o')
			severity_number = $this.Level
			severity_text   = [Logger]::GetSeverity($this.Level)
			body            = $this.Message
			resource        = $Script:ResourceAttributes
		}
		if ($this.Attributes) {
			$logEntry.attributes = $this.Attributes
		}
		return ($logEntry | ConvertTo-Json -Depth 10 -Compress)
	}
}

$Script:ResourceAttributes = @{
    'service.name'           = $env:PSLOGGER_SERVICENAME ?? 'PsLogger'
    'service.version'        = $env:PSLOGGER_SERVICEVERSION ?? "$($MyInvocation.MyCommand.ScriptBlock.Module.Version)"
    'host.name'              = $env:PSLOGGER_HOSTNAME ?? [System.Environment]::MachineName
    'deployment.environment' = $env:PSLOGGER_ENVIRONMENT ?? 'development'
}

$Script:SpanEndpoint = $env:PSLOGGER_SPAN_ENDPOINT ?? 'http://localhost:4318/v1/traces'

try {
	Get-ChildItem "$(Split-Path -Parent $MyInvocation.MyCommand.Path)/Public/*.ps1" | ForEach-Object {. $_}
}
catch {
	Write-Error -Message "Importing module PsLogger failed: $($_.Exception.ToString())"
}