Add-AdfsWebApiApplication command not working in Powershell 7

[thomaslazar]

Issue originally reported here. Was told to move it to this repository.

Steps to reproduce

1. Windows System with ADFS Installed
2. Have following AdfsAccessControlPolicy in place

Get-AdfsAccessControlPolicy -name "Permit specific claim"

Name           : Permit specific claim
Identifier     : Permitspecificclaim
IsBuiltIn      : False
RpUsageCount   : 4
LastUpdateTime : 25.03.2019 15:40:00
Description    :
PolicyMetadata : RequireFreshAuthentication:False
                 IssuanceAuthorizationRules:
                 {
                   Permit users
                     with <ClaimsParameter_0> in the request
                 }
                 ParameterDescription:
                 {
                   <ClaimsParameter_0>: Specify condition with ClaimType, Operator and Value using hashtable.
                 }

3. Run script from following Gist Setup-AdfsApplicationGroup.ps1

Specifically this bit is the problem.

$acl = @{
    ClaimsParameter_0 = @{ ClaimType = 'http://schemas.microsoft.com/ws/2008/06/identity/claims/role'; Operator = 'Contains'; Value = $CustomerGroup }
}

Add-AdfsWebApiApplication -ApplicationGroupIdentifier $CustomerId -Identifier "$CustomerId" -Name "$CustomerId - Web Application" -AccessControlPolicyName "Permit specific claim" -AccessControlPolicyParameters $acl -TokenLifetime 15

Expected behavior

Should run and create an AdfsWebApplication

Actual behavior

Add-AdfsWebApiApplication: ADMIN0144: SpecificClaimCondition and SpecificClaimException parameter 'ClaimsParameter_0' should be assigned through a hashtable that specifies ClaimType, Operator and Value. If multiple conditions are desired, use an array of hashtables.

Additional information

I used dotPeak to look into Microsoft.IdentityServer.dll. The problem seems to be the following check inside the ParameterInterface.cs AssignSpecificClaimParemeterFromPSHInput method , which is not working in PowerShell 7 but is working in PowerShell 5.1

if (!(value is Hashtable hashtable))
  throw new InvalidDataException(Microsoft.IdentityServer.SR.GetString("ADMIN0144", (object) specific.Label));

The content of the variable value is the content that got passed into the AccessControlPolicyParameters parameter of the Add-AdfsWebApiApplication command.

It does not matter what you put into the AccessControlPolicyParameters parameter. It always triggers this check and throws the exception.

Environment data

PS C:\Temp> $PSVersionTable

Name                           Value
----                           -----
PSVersion                      7.0.0
PSEdition                      Core
GitCommitId                    7.0.0
OS                             Microsoft Windows 10.0.17763
Platform                       Win32NT
PSCompatibleVersions           {1.0, 2.0, 3.0, 4.0…}
PSRemotingProtocolVersion      2.3
SerializationVersion           1.1.0.1
WSManStackVersion              3.0