How can I catch Browsererrors like 504 in a SharePoint2013 Warm-Up Skript? - powershell

Question

I am a freshman at PowerShell and I try to implement a SharePoint Warm-Up Skript.
This Skript is not originally mine, i only edited a existing one. Now it run nicely. But if a error occured like a DNS look up fail i want a Output in my Logfile like: "A DNS look up fail occured at URL..."
I want to catch the Browsererrors 400, 404 and 504. How can I catch them?
Here my code so far:
Function WarmUp() {
# Get URL list
Add-PSSnapIn Microsoft.SharePoint.PowerShell -ErrorAction SilentlyContinue
$was = Get-SPWebApplication -IncludeCentralAdministration
$was |? {$_.IsAdministrationWebApplication -eq $true} |% {$caTitle = Get-SPWeb $_.Url | Select Title}
# Warm up SharePoint web applications
Write-Host "Opening Web Applications..."
$global:ie = New-Object -Com "InternetExplorer.Application"
$global:ie.Navigate("about:blank")
$global:ie.Visible = $true
$global:ieproc = (Get-Process -Name iexplore)|? {$_.MainWindowHandle -eq $global:ie.HWND}
#Navigate here to all Applications, Collections and sites
# Close IE window
if ($global:ie) {
Write-Host "Closing IE"
$global:ie | Stop-Process -Force -ErrorAction SilentlyContinue
}
$global:ieproc | Stop-Process -Force -ErrorAction SilentlyContinue
# Clean Temporary Files
Remove-item "$env:systemroot\system32\config\systemprofile\appdata\local\microsoft\Windows\temporary internet files\content.ie5\*.*" -Recurse -ErrorAction SilentlyContinue
Remove-item "$env:systemroot\syswow64\config\systemprofile\appdata\local\microsoft\Windows\temporary internet files\content.ie5\*.*" -Recurse -ErrorAction SilentlyContinue
}
Function IENavigateTo([string] $url, [int] $delayTime = 500) {
# Navigate to a given URL
if ($url) {
if ($url.ToUpper().StartsWith("HTTP")) {
Write-Host " Navigating to $url"
try {
$global:ie.Navigate($url)
#If the certificate is invalid, bypass the error to show the context.
if ($global:ie.document.url -Match "invalidcert")
{
"Bypassing SSL Certificate Error Page";
$sslbypass=$global:ie.Document.getElementsByTagName("a") | where-object {$_.id -eq "overridelink"};
$sslbypass.click();
"Sleep for 5 seconds while final page loads";
start-sleep -s 5;
}
} catch {
try {
$pid = $global:ieproc.id
} catch {}
Write-Host " IE not responding. Closing process ID $pid"
$global:ie | Stop-Process -Force -ErrorAction SilentlyContinue
$global:ieproc | Stop-Process -Force -ErrorAction SilentlyContinue
$global:ie = New-Object -Com "InternetExplorer.Application"
$global:ie.Navigate("about:blank")
$global:ie.Visible = $true
$global:ieproc = (Get-Process -Name iexplore)|? {$_.MainWindowHandle -eq $global:ie.HWND}
}
IEWaitForPage $delayTime
}
}
}
Function IEWaitForPage([int] $delayTime = 500) {
# Wait for current page to finish loading
$loaded = $false
$loop = 0
$maxLoop = 20
while ($loaded -eq $false) {
$loop++
# Wait until the page is loaded.
While ($global:ie.ReadyState -ne 4) {
Start-Sleep -Seconds 2
Write-Host "Busy!"
}
if ($loop -gt $maxLoop) {
$loaded = $true
}
[System.Threading.Thread]::Sleep($delayTime)
# If the browser is not busy, the page is loaded
if (-not $global:ie.Busy)
{
$loaded = $true
}
}
}
#Main
if(-not(Test-Path "C:\Logs\SharePoint\WarmUpLogTest")){New-Item -ItemType Directory -Path "C:\Logs\SharePoint\WarmUpLogTest"}
Start-Transcript -Path ("C:\Logs\SharePoint\WarmUpLogTest\SPWarmUp{0:yyyy-MM-dd}.txt" -f $(get-date)) -Append
WarmUp
Stop-Transcript

Answer 1

If you run powershell V3 or newest you can add this on top of your IENavigateTo
try{invoke-webrequest $url}
catch{$_.errordetails|select -expand message}
without V3 you can try something like
$request = [System.Net.WebRequest]::Create($url)
try{$response = $request.GetResponse() }catch{$_.exception.message}