Trying to Use Power shell Script to test availability of website - powershell

Question

I am trying to use a powershell script to test the availability of certain websites. I have a script here that writes "Site is OK" if the site returns a http 200 code. It should return "The Site may be down, please check!" If it returns any other code. I put in 'https://www.google.com/cas76' which should obviously return a 404 error however the script returns "Site is ok" How should I go about fixing my code so it returns "The Site may be down, please check!"
Tried putting in websites that would obviously not return a 200 code.
# First we create the request.
$HTTP_Request = [System.Net.WebRequest]::Create('https://www.google.com/cas76')
# We then get a response from the site.
$HTTP_Response = $HTTP_Request.GetResponse()
# We then get the HTTP code as an integer.
$HTTP_Status = [int]$HTTP_Response.StatusCode
If ($HTTP_Status -eq 200) {
Write-Host "Site is OK!"
}
Else {
Write-Host "The Site may be down, please check!"
}
# Finally, we clean up the http request by closing it.
$HTTP_Response.Close()
Code acknowledges that there is a 404 error
Exception calling "GetResponse" with "0" argument(s): "The remote server returned an error: (404) Not Found."
At C:\Users\TX394UT\Desktop\Web_Bot_Project\WebsiteMonitoring.ps1:6 char:1
+ $HTTP_Response = $HTTP_Request.GetResponse()
However, Site is OK! Prints on the console.

Answer 1

the way that the webclient handles returned errors is ... odd. [grin]
that message is treated as a non-terminating error and needs to be handled as such. the most obvious way is with Try/Catch/Finally. when capturing the exception message, the 404 StatusCode is converted to the text value for it - NotFound.
$TestUrl = 'https://www.google.com/cas76'
try
{
$Response = (Invoke-WebRequest -Uri $TestUrl -ErrorAction Stop).StatusCode
}
catch
{
$Response = $_.Exception.Response.StatusCode
}
$Response
output for the bad url = NotFound
output for a good url = 200