PowerShell Webservices Probe

The following script reads URL’s from an array to check if specific web services are online. When the script finds that one or more services are offline it sends an e-mail message (HTML). A TEXT version of the message is created in the Windows EventLog.

Het script uses custum functions: fnSendMail en fnWriteEventLog om berichten af te handelen.

# Global config settings...
[string]$sSMTPServer1 = "smtp.example.org"
[string]$sSubject1 = "EXAMPLE:WebService probes..."
[string]$sToAddress1 = "test@example.org"
[string]$sEventLogSource = "EVENTLOGSOURCE"
[switch]$swAlarm = $false
[array]$aWebServices1 = @(
   "https://example.org/webService?WSDL",
   "https://example.org/webService?WSDL",
)

# Functions and procedures...
function fnProbeWebSvc() {
  param (
    [string]$sWebSvcWSDL
  )
  $oWebSvc1 = New-WebServiceProxy -Uri $sWebSvcWSDL
  if ($oWebSvc1) {
    [switch]$swWebSvcIsAlive = $true
  } else {
    [switch]$swWebSvcIsAlive = $false
  }  
  return $swWebSvcIsAlive
}

# Start Main script...
# Create array for results...
[array]$aWebServiceState = @()

# Fill table from array...
foreach ($row1_aWebServices1 in $aWebServices1) {
  $oWebServiceState = New-Object PSObject -Property @{
    'WebService' = $row1_aWebServices1
    'IsAlive' = (fnProbeWebSvc -sWebSvcWSDL $row1_aWebServices1) }
  # FLip Alarm status if fnProbeWebSvc return value is false...  
  if ($oWebServiceState.IsAlive -eq $false) {[switch]$swAlarm = $true}
  $aWebServiceState += $oWebServiceState
}

# Build HTML and TEXT body w. array data if alarm status is set to true...
if ($swAlarm -eq $true) {
  
  # Body header HTML...
  $sbBody1_HTML = New-Object System.Text.StringBuilder
  [void]$sbBody1_HTML.Append("<html><head><title></title></head><body>`r`n")
  [void]$sbBody1_HTML.Append("<table><tbody><tr bgcolor='grey'><th>WebService</th><th>IsAlive</th></tr>`r`n")

  # Body header TEXT...
  $sbBody1_TEXT = New-Object System.Text.StringBuilder
  [void]$sbBody1_TEXT.Append("Webservice(s) offline. Contact your administrators.`r`n`r`n")

  # Build table rows from array...
  foreach ($row1_aWebServiceState in $aWebServiceState) {
    # Build table rows HTML...
    [void]$sbBody1_HTML.Append("<tr bgcolor='lightblue'><td>")
    [void]$sbBody1_HTML.Append($row1_aWebServiceState.WebService)
    # Row Coloring...
    if ($row1_aWebServiceState.IsAlive -eq $true) {
      [void]$sbBody1_HTML.Append("</td><td bgcolor='lightgreen'>")
    } else {
      [void]$sbBody1_HTML.Append("</td><td bgcolor='lightpink'>")
    }
    [void]$sbBody1_HTML.Append($row1_aWebServiceState.IsAlive)
    [void]$sbBody1_HTML.Append("</td></tr>")

    # Build table rows TEXT (only show failed services...
      if ($row1_aWebServiceState.IsAlive -eq $false) {
        [void]$sbBody1_TEXT.Append($row1_aWebServiceState.WebService)
        [void]$sbBody1_TEXT.Append(": ")
        [void]$sbBody1_TEXT.Append($row1_aWebServiceState.IsAlive)
        [void]$sbBody1_TEXT.Append("`r`n")
      }
  }

  # Mail body footer...
  [void]$sbBody1_HTML.Append("</tbody></table>`r`n")
  [void]$sbBody1_HTML.Append("<html><head><title></title></head><body>`r`n")

  # Send HTML body in mail to admins...
  [string]$sBody1 = $sbBody1_HTML.ToString()
  fnSendMail -sSMTPSrvrName $sSMTPServer1 -sFrom (fnGetFQDN -swIsEmail) -sTo $sToAddress1 -sSubject $sSubject1 -sBody $sBody1 -swIsBodyHTML

  # Send text body to eventlog...
  fnWriteEventLog -sNode "NODENAME" -sMessage $sbBody1_TEXT.ToString() 
}