Sinks (Console/File/JSON)

Wire different outputs for your logs. This sample writes to:

  • Console (human-friendly text)
  • Rolling text file logs/sinks-text<timestamp>.log
  • Rolling JSON file logs/sinks-json<timestamp>.log

For more sinks (HTTP, EventLog, Syslog, Seq), see the Logging guide.

Full source

File: pwsh/tutorial/examples/5.4-Sinks.ps1

<#
    Sample demonstrating sinks: console, text file, and JSON file.
    - 'text' logger: writes to console + logs/sinks-text.log
    - 'json' logger: writes to logs/sinks-json.log with JSON formatter
    FileName: 5.4-Sinks.ps1
#>

param(
    [int]$Port = 5000,
    [IPAddress]$IPAddress = [IPAddress]::Loopback
)

$text = New-KrLogger |
    Set-KrLoggerLevel -Value Information |
    Add-KrSinkConsole |
    Add-KrSinkFile -Path '.\logs\sinks-text.log' -RollingInterval Hour |
    Register-KrLogger -Name 'text' -PassThru

$json = New-KrLogger |
    Set-KrLoggerLevel -Value Debug |
    Add-KrSinkFile -Path '.\logs\sinks-json.log' -Formatter (Get-KrSinkJsonFormatter) -RollingInterval Hour |
    Register-KrLogger -Name 'json' -PassThru

New-KrServer -Name "Sinks Demo"
Add-KrEndpoint -Port $Port -IPAddress $IPAddress


Enable-KrConfiguration

Add-KrMapRoute -Verbs Get -Path "/text" -ScriptBlock {
    Write-KrLog -Logger $text -Level Information -Message "Text sink example"
    Write-KrTextResponse -InputObject "text" -StatusCode 200
}

Add-KrMapRoute -Verbs Get -Path "/json" -ScriptBlock {
    Write-KrLog -Logger $json -Level Debug -Message "Json sink example" -Values @{ Example = $true }
    Write-KrTextResponse -InputObject "json" -StatusCode 200
}

# Start the server and close all the loggers when the server stops
# This is equivalent to calling Close-KrLogger after Start-KrServer
Start-KrServer -CloseLogsOnExit

Step-by-step

  1. Create text logger with minimum Information, add Console + File sinks.
  2. Create json logger with minimum Debug, add File sink with Get-KrJsonFormatter.
  3. Standard server + listener + PowerShell runtime.
  4. Apply config: call Enable-KrConfiguration to commit the listener/runtime.
  5. Routes:
    • /text writes an Information event via the text logger.
    • /json writes a Debug event with an extra property via the json logger.
  6. Start: Start-KrServer begins processing requests.

Try it

Save the sample locally so the log files are easy to find. Copy the contents of pwsh/tutorial/examples/5.4-Sinks.ps1 into a new file in an empty working folder (for example, sinks-demo.ps1), then run:

# From your working folder
pwsh .\sinks-demo.ps1
curl http://127.0.0.1:5000/text
curl http://127.0.0.1:5000/json
Get-Content .\logs\sinks-text*.log -Tail 20
Get-Content .\logs\sinks-json*.log -Tail 20

Expected: sinks-text*.log contains human-readable events; sinks-json<timestamp>.log contains JSON entries.

Customizing

  • Restrict console to higher level: Add-KrSinkConsole -RestrictedToMinimumLevel Warning.
  • Change rolling interval or retention on file sinks.
  • Add HTTP/Syslog/EventLog sinks; add structured properties.
  • Set one logger as default or pass to New-KrServer to enable Kestrun framework logs.

Troubleshooting

Symptom Cause Fix
Empty JSON file No Debug events written Lower minimum for json or send Debug events
Garbled console output Custom template mismatch Remove/adjust OutputTemplate
File not created Path/permissions/empty stream Check path; trigger requests
Cannot delete/rename log file Logger still open / file handle Run Close-KrLogger; let the process exit

References

Previous / Next

Go back to Enrichment & Correlation IDs or continue to Sinks (HTTP/EventLog/Syslog). Guide: Logging (Concepts)