New-PSUApiResponse unexpected behavior (with VMware PowerCLI)

PowerShell Universal
1 
Product: PowerShell Universal
Version: 1.5.11

I have written a short endpoint, which gets some data from virtual machines in vCenter (using PowerCLI).

Connect-VIServer vcenter.domain.local 
$result = get-VM vms* | Select Name,NumCPU,MemoryGB | ConvertTo-Json -Compress
New-PSUApiResponse -Body $result -StatusCode 200 -ContentType 'application/json'

On the client side I call the endpoint by Invoke-RestMethod …

The result has 2 elements. The first seems to come from Connect-VIServer, the second is the expected result.

I’ve found a workaround:

Connect-viserver vcenter.domain.local  | Out-Null

Is this behavior expected? Is there any documentation what objects are passed by New-PSUApiResponse - in addition to the Body-parameter?

Thanks
Roland

2

This is expected behavior. APIs will return whatever is written to the pipeline. If Connect-VIServer returns an object, that object will be returned along with the New-PSUAPIResponse. New-PSUAPIResponse will return an object and if it’s the only object returned it will use that for customizing the response.

3

You will encounter more issues, this is because of runspace.

What I have done is that I invoke-script instead from the dashboard and run the vcenter in the script sections.

This don’t effect the horizon module.

Here is my thread about it.

Also include links to VMware

4

It is not related to a Dashboard, but an API endpoint instead. Adam reported back, that the behavior is expected - and so I will continue to use | Out-Null to get rid of the output of Connect-VIServer.

Thanks

5

So New-PSUApiResponse doesn’t actually return the data immediatly, but “only” builds the object, that will be returned at the end of the endpoint? And because the result of New-PSUApiResponse is not written to a variable or Out-Null the result gets to the output pipeline. Have I got it right, now?

Thanks
Roland

6

Correct. We don’t exit early from the script block to return a result since only a single response can be returned. We wait until the scriptblock has executed entirely.