web services - PowerShell script to check the status of a URL

Question

Similar to this question here I am trying to monitor if a set of website links are up and running or not responding. I have found the same PowerShell script over the Internet.

However, instead of direct website links I need to check more specific links, for example:

http://mypage.global/Chemical/

http://maypage2:9080/portal/site/hotpot/

When I am trying to check on the status of these links, I get the following output:

URL    StatusCode    StatusDescription    ResponseLength    TimeTaken
http://mypage.global/Chemical/    0
http://maypage2:9080/portal/site/hotpot/    0

The above links requires me to be connected to the VPN, but I can access these links from the browser.

Output of Invoke-WebRequest -Uri https://stackoverflow.com/questions/20259251/powershell-script-to-check-the-status-of-a-url:

PS C:Users682126> Invoke-WebRequest -Uri https://stackoverflow.com/questions/20259251/powershell-script-to-check-the-status-of-a-url

The term 'Invoke-WebRequest' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is correct and try again.

At line:1 char:18
+ Invoke-WebRequest <<<<  -Uri https://stackoverflow.com/questions/20259251/powershell-script-to-check-the-status-of-a-url > tmp.txt
    + CategoryInfo          : ObjectNotFound: (Invoke-WebRequest:String) [], CommandNotFoundException
    + FullyQualifiedErrorId : CommandNotFoundException

$PSVersionTable

Name                           Value
----                           -----
CLRVersion                     2.0.50727.5472
BuildVersion                   6.1.7601.17514
PSVersion                      2.0
WSManStackVersion              2.0
PSCompatibleVersions           {1.0, 2.0}
SerializationVersion           1.1.0.1
PSRemotingProtocolVersion      2.1

Answer 1

I recently set up a script that does this.

As David Brabant pointed out, you can use the System.Net.WebRequest class to do an HTTP request.

To check whether it is operational, you should use the following example code:

# First we create the request.
$HTTP_Request = [System.Net.WebRequest]::Create('http://google.com')

# 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.
If ($HTTP_Response -eq $null) { } 
Else { $HTTP_Response.Close() }