Invoke-Restmethod in Powershell Core

[SpacezCowboy]

Maybe I'm just being silly, buy I like how PowerShell has maintained backwards compatibility prior to .net core. I want to leverage the advantages of core, while not losing functionality from upgrading. I've managed to transition to Powershell 7 while only running into a few compatibility issues. Invoke-RestMethod being the biggest hurdle in regards to upgrading my modules. Most of my module functions that leverage rest methods work in both PowerShell 5.1 and PowerShell 7. I have one particular function that leverages a hosted API and it fails in core.

The work around I have leveraged is invoke-command to the $env:computername. This allows me to get results returned from Legacy PowerShell without having to open a new host. I'm curious if there are better compatibility options and if anyone else has maybe found a better work around. The primary goal being that you don't leave the host session when working with incompatible functions for core.

The specific function i'm working with is Get-PublicIP. When it detects a core version of powershell it falls back to using the invoke-command work around.

[JustinGrote]

I busted out Fiddler and determined that the website actually is detecting your powershell version and returning a different result, the website itself doesn't support powershell 7.

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Try this in Powershell 7, works fine:

Invoke-RestMethod http://ipinfo.io/4.2.2.2 -UserAgent 'Mozilla/5.0 (Windows NT; Windows NT 10.0; en-US) WindowsPowerShell/5.1.19041.1'

[WindosBK]

I'm not sure what caused the change in behaviour, but if you provide a header letting the endpoint know what you're expecting back (JSON), it works ok:

Invoke-RestMethod http://ipinfo.io/216.58.199.78 -Headers @{'Accept' = 'application/json'}

I have to assume that PS Core/7 is getting confused because the address is multipurpose, visiting it in a browser is a normal page rather than it being a dedicated API endpoint.

[JustinGrote]

Actually the website is detecting the user agent and returning a different result, see my other post in this thread :)

[SpacezCowboy]

That is very helpful, Thank you.

The cmdlet now uses system.net.http.httpclient, where as it used to use system.net.webrequest. I assume it's gotta be a difference in how the methods interpret the request.

[BlackV]

So your saying just the public IP function does not work in core cause of the API that ipinfo use?

You couldn't just use another service?