Check default collector metrics with promtool

Signed-off-by: Ben Reedy <breed808@breed808.com>
2026-02-08 05:56:37 +00:00 · 2022-01-03 13:33:45 +10:00
parent 36f033ae57
commit 14d3e4ea28
3 changed files with 148 additions and 2 deletions
--- a/tools/promtool.ps1
+++ b/tools/promtool.ps1
@@ -0,0 +1,115 @@
+$ErrorActionPreference = 'Stop'
+Set-StrictMode -Version 3
+
+if (-not (Test-Path -Path '.\windows_exporter.exe')) {
+    Write-Output ".\windows_exporter.exe not found. Consider running \`go build\` first"
+}
+
+# Powershell pipes & Get-Content command rather unhelpfully add a carriage return at the end of the string, so
+# passing the string as bytes is a messy but necessary workaround for processes that are sensitive to
+# line endings, like promtool.
+function Start-RawProcess {
+    param(
+        # String to pass to $CommandName via STDIN
+        [Parameter(Mandatory=$true)][String]$InputVar,
+        # Command to run
+        [Parameter(Mandatory=$true)][String]$CommandName,
+        # Arguments provided to $CommandName
+        [Parameter(Mandatory=$false)][String[]]$CommandArgs
+    )
+    # Buffer & initial size of MemoryStream
+    $BufferSize = 4096
+
+    # Convert text to bytes and write to MemoryStream
+    [byte[]]$InputBytes = [Text.Encoding]::UTF8.GetBytes($InputVar)
+    $MemStream = New-Object -TypeName System.IO.MemoryStream -ArgumentList $BufferSize
+    $MemStream.Write($InputBytes, 0, $InputBytes.Length)
+    [Void]$MemStream.Seek(0, 'Begin')
+
+    # Setup stdin\stdout redirection for our process
+    if ($CommandArgs) {
+        $StartInfo = New-Object -TypeName System.Diagnostics.ProcessStartInfo -Property @{
+            FileName = $CommandName
+            UseShellExecute = $false
+            RedirectStandardInput = $true
+            RedirectStandardError = $true
+            Arguments = $CommandArgs
+        }
+    } else {
+        $StartInfo = New-Object -TypeName System.Diagnostics.ProcessStartInfo -Property @{
+            FileName = $CommandName
+            UseShellExecute = $false
+            RedirectStandardInput = $true
+            RedirectStandardError = $true
+        }
+    }
+
+    # Create new process
+    $Process = New-Object -TypeName System.Diagnostics.Process
+
+    # Assign previously created StartInfo properties
+    $Process.StartInfo = $StartInfo
+    # Start process
+    [void]$Process.Start()
+
+    # Pipe data
+    $Buffer = New-Object -TypeName byte[] -ArgumentList $BufferSize
+    $StdinStream = $Process.StandardInput.BaseStream
+
+    try {
+        do {
+            $ReadCount = $MemStream.Read($Buffer, 0, $Buffer.Length)
+            $StdinStream.Write($Buffer, 0, $ReadCount)
+            $StdinStream.Flush()
+        }
+        while($ReadCount -gt 0)
+    }
+    catch
+    {
+       throw 'Error streaming buffer to STDIN'
+    } finally {
+        # Close streams
+        $StdinStream.Close()
+        $MemStream.Close()
+    }
+    $Process.WaitForExit()
+    if ($Process.ExitCode -ne 0) {
+        Write-Host $Process.StandardError.ReadToEnd()
+    }
+
+    return $Process.ExitCode
+}
+
+# cd to location of script
+$script_path = $MyInvocation.MyCommand.Path
+$working_dir = Split-Path $script_path
+Push-Location $working_dir
+
+$temp_dir = Join-Path $env:TEMP $(New-Guid) | ForEach-Object { mkdir $_ }
+
+# Start process in background, awaiting HTTP requests.
+# Use default collectors, port and address: http://localhost:9182/metrics
+$exporter_proc = Start-Process `
+    -PassThru `
+    -FilePath .\windows_exporter.exe `
+    -ArgumentList "--log.level=debug" `
+    -WindowStyle Hidden `
+    -RedirectStandardOutput "$($temp_dir)/windows_exporter.log" `
+    -RedirectStandardError "$($temp_dir)/windows_exporter_error.log"
+
+# Give exporter some time to start
+Start-Sleep 3
+
+# Omit metrics from client_golang library; we're not responsible for these
+$skip_re = "^[#]?\s*(HELP|TYPE)?\s*go_"
+
+# Need to remove carriage returns, as promtool expects LF line endings
+$output = ((Invoke-WebRequest -UseBasicParsing -URI http://127.0.0.1:9182/metrics).Content) -Split "`r?`n" | Select-String -NotMatch $skip_re | Join-String -Separator "`n"
+# Join the split lines back to a single String (with LF line endings!)
+$output = $output -Join "`n"
+Stop-Process -Id $exporter_proc.Id
+$ExitCode = Start-RawProcess -InputVar $output -CommandName promtool.exe -CommandArgs @("check metrics")
+if ($ExitCode -ne 0) {
+    Write-Host "Promtool command returned exit code $($ExitCode). See output for details."
+    EXIT 1
+}