Dfyjkt

I am still new to Powershell and haven't been able to find anything on this. I am running a REST GET request to a URI which I know for a fact returns a 404 from the server since the resource is not found.

I would like to be able to run a conditional that checks if it's a 404 and skip over it for further processing if this is the case however when I assign the request to a variable, then calling on that later, it just gives me the contents of what my request was. I have never seen anything like this before in other languages...

My basic premise is the following. I first fetch all group names, then loop through that array of names, include the current one in a new URL and make an additional request for that specific group which looks for a SHIFT which will always have the same name. If the group doesn't have that shift by name I want to skip to the next group, otherwise alter some attributes of that newly found shift object.

Here is what my code looks like, as you can see it's not acting correctly

[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
$user = '******'
$pass = ConvertTo-SecureString '*******' -AsPlainText -Force
$cred = New-Object -TypeName System.Management.Automation.PSCredential -ArgumentList $user, $pass
$req = Invoke-WebRequest -Credential $cred -Uri https://********-np.xmatters.com/api/xm/1/groups
$res = ConvertFrom-Json $req.Content
$content = $res.data

$base = "https://********-np.xmatters.com/api/xm/1/groups"
$group_name = $content[0].targetName
$path = "$base/$group_name/shifts/MAX-Default Shift"

$shift = Invoke-RestMethod -Credential $cred -Uri $path

Write-Host '-----------------------'
Write-Host $shift
Write-Host '-----------------------'



... RESPONSE BELOW ....



Invoke-RestMethod : The remote server returned an error: (404) Not Found.
At \MMFILE********$MyDocumentsGroup Supers PReliminary.ps1:16 char:10
+ $shift = Invoke-RestMethod -Credential $cred -Uri $path
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
 + CategoryInfo : InvalidOperation: (System.Net.HttpWebRequest:HttpWebRequest) [Invoke-RestMethod], WebException
 + FullyQualifiedErrorId : WebCmdletWebResponseException,Microsoft.PowerShell.Commands.InvokeRestMethodCommand

-----------------------
@id=***********; group=; name=MAX-Default Shift; description="; start=2018-08-21T04:00:00.000Z; end=2018-08-22T04:00:00.000Z; timezone=America/New_York; recurrence=;
 links=
-----------------------

PS C:WINDOWSsystem32> 

What I would like to do is something like, in shorthand code, if $shift.code == 404 ... skip ... else ... run additional query

You could suppress the error message via Try..Catch and in so doing allow the script to continue:

Try 
 $Shift = Invoke-RestMethod http://www.google.com/fakeurl -ErrorAction Stop
 #Do other things here if the URL exists..
 Catch 
 if ($_.Exception -eq 'The remote server returned an error: (404) Not Found.') 
 #Do other things here that you want to happen if the URL does not exist..
 

Note this will hide all terminating errors from Invoke-ResetMethod. You could then use an if statement to see if the exception was a 404 and then perform further actions accordingly.

You need to use a try ... catch.

$code = ""

try
 $shift = Invoke-RestMethod -Credential $cred -Uri $path

catch
 $code = $_.Exception.Response.StatusCode.value__


if($code -eq "404")

 continue
 # Other things

else


 Write-Host '-----------------------'
 Write-Host $shift
 Write-Host '-----------------------'