Framework/Helpers/ActiveDirectoryHelper.ps1

Set-StrictMode -Version Latest 
class ActiveDirectoryHelper {

        static [PSObject] GetADAppServicePrincipalByAppId($ApplicationId)
        {
            $TenantId = ([AccountHelper]::GetCurrentAzAcontext()).Tenant.Id
            $ApiVersion = "1.6"
            $GraphApiUrl = [WebRequestHelper]::GraphApiUri + $TenantId + "/servicePrincipals/{0}?api-version=$ApiVersion"
            $uri = [string]::Format($GraphApiUrl + "&`$filter=(appId eq '{1}')", [string]::Empty , $ApplicationId);
            $resultObject = [WebRequestHelper]::InvokeGetWebRequest($uri);
            
            #this returns array of objects. Actual object is present at 1st index
            if($resultObject)
            {
                return $resultObject[0]
            }
            else
            {
                return $null
            }
            
        }

        static [void] UpdateADAppServicePrincipalCredential(
            $ApplicationID,
            [System.Security.Cryptography.X509Certificates.X509Certificate2]
            $PublicCert,
            [System.DateTime]
            $NotBefore = (Get-Date).AddDays(-1),
            [System.DateTime]
            $NotAfter = $NotBefore.AddMonths(6),
            [string]
            $Delete = "False"
        )
        {
            #Initialization
            $TenantId = ([AccountHelper]::GetCurrentAzAcontext()).Tenant.Id
            $ApiVersion = "1.6"
            $GraphApiUrl = [WebRequestHelper]::GraphApiUri + $TenantId + "/servicePrincipals/{0}?api-version=$ApiVersion"
            $addMode = $False;
            $startDateString = $NotBefore.ToString("O");
            $endDateString = $NotAfter.ToString("O");

            if($Delete -eq "False")
            {
                if(-not $PublicCert)
                {
                    throw "Public Certificate cannot be null"
                }
            }

            $servicePrincipal =  [ActiveDirectoryHelper]::GetADAppServicePrincipalByAppId($ApplicationID)

            if($Delete -eq "False")
            {
                if($null -eq $servicePrincipal)
                {
                    $addMode = $True;
                    $servicePrincipal = New-Object -TypeName PSObject;
                    $servicePrincipal | Add-Member -MemberType NoteProperty -Name appId -Value $ApplicationID -PassThru
                }

                $publicCertString = [System.Convert]::ToBase64String($PublicCert.GetRawCertData());

                $credentialObject = New-Object -TypeName PSObject
                $credentialObject | Add-Member -MemberType NoteProperty -Name endDate -Value $endDateString -PassThru `
                                    | Add-Member -MemberType NoteProperty -Name startDate -Value $startDateString -PassThru

                $credentialObject | Add-Member -MemberType NoteProperty -Name type -Value "AsymmetricX509Cert" -PassThru `
                                        | Add-Member -MemberType NoteProperty -Name usage -Value "Verify" -PassThru `
                                        | Add-Member -MemberType NoteProperty -Name value -Value $publicCertString

                if ([bool](Get-Member -InputObject $servicePrincipal -Name "keyCredentials"))
                {
                    [System.Collections.ArrayList]$keys = $servicePrincipal.keyCredentials
                    $credentialList = $keys.Add($credentialObject)
                    $servicePrincipal.keyCredentials = $keys
                }
                else
                {
                    $servicePrincipal | Add-Member -MemberType NoteProperty -Name keyCredentials -Value @($credentialObject)
                }
            }
            elseif($Delete -eq "True")
            {    
                $servicePrincipal.keyCredentials = $servicePrincipal.keyCredentials | Where-Object { 
                    [System.DateTime]::Parse($_.startDate).ToUniversalTime() -ne $NotBefore.ToUniversalTime() `
                    -and [System.DateTime]::Parse($_.endDate).ToUniversalTime() -ne $NotAfter.ToUniversalTime() `
                } 
            }
            elseif($Delete -eq "All")
            {
                $servicePrincipal.keyCredentials = @()
            }
            $servicePrincipal = $servicePrincipal | Select-Object * -ExcludeProperty "requiredResourceAccess"  

            $body = ConvertTo-Json -InputObject $servicePrincipal
            $operation = [string]::Empty;
            $requestUri = [string]::Empty;
            $GraphAPIAccessToken = Get-AzSKAccessToken -ResourceAppIdURI "https://graph.windows.net/";
            if($addMode)
            {
                $operation = "POST";
                $requestUri = [string]::Format($GraphApiUrl, [string]::Empty);
            }
            else
            {
                $operation = "PATCH";
                $requestUri = [string]::Format($GraphApiUrl, $servicePrincipal.objectId);
            }

            $updateResult = Invoke-RestMethod `
                            -Method $operation `
                            -Uri $requestUri `
                            -Headers @{ Authorization = "Bearer " + $GraphAPIAccessToken } `
                            -ContentType "application/json" `
                            -Body $body `
                            -UseBasicParsing

            if($null -eq $updateResult)
            {
                 Throw "There was a problem while updating the service principal with new certificate"    
            }
    }

        static [PSObject] GetADAppByAppId($ApplicationId)
        {
            $TenantId = ([AccountHelper]::GetCurrentAzAcontext()).Tenant.Id
            $ApiVersion = "1.6"
            $GraphApiUrl = [WebRequestHelper]::GraphApiUri + $TenantId + "/applications/{0}?api-version=$ApiVersion"
            $uri = [string]::Format($GraphApiUrl + "&`$filter=(appId eq '{1}')", [string]::Empty , $ApplicationId);
            $resultObject = [WebRequestHelper]::InvokeGetWebRequest($uri);
            
            #this returns array of objects. Actual object is present at 1st index
            if($resultObject)
            {
                return $resultObject[0]
            }
            else
            {
                return $null
            }
            
        }
        
        static [void] UpdateADAppCredential(
            $ApplicationID,
            [System.Security.Cryptography.X509Certificates.X509Certificate2]
            $PublicCert,
            [System.DateTime]
            $NotBefore = (Get-Date).AddDays(-1),
            [System.DateTime]
            $NotAfter = $NotBefore.AddMonths(6),
            [string]
            $Delete = "False"
        )
        {
            #Initialization
            $TenantId = ([AccountHelper]::GetCurrentAzAcontext()).Tenant.Id
            $ApiVersion = "1.6"
            $GraphApiUrl = [WebRequestHelper]::GraphApiUri + $TenantId + "/applications/{0}?api-version=$ApiVersion"
            $startDateString = $NotBefore.ToString("O");
            $endDateString = $NotAfter.ToString("O");

            if($Delete -eq "False")
            {
                if(-not $PublicCert)
                {
                    throw "Public Certificate cannot be null"
                }
            }

            $ADApplication =  [ActiveDirectoryHelper]::GetADAppByAppId($ApplicationID)
            if($Delete -eq "False")
            {
                $publicCertString = [System.Convert]::ToBase64String($PublicCert.GetRawCertData());

                $credentialObject = New-Object -TypeName PSObject
                $credentialObject | Add-Member -MemberType NoteProperty -Name endDate -Value $endDateString -PassThru `
                                    | Add-Member -MemberType NoteProperty -Name startDate -Value $startDateString -PassThru

                $credentialObject | Add-Member -MemberType NoteProperty -Name type -Value "AsymmetricX509Cert" -PassThru `
                                        | Add-Member -MemberType NoteProperty -Name usage -Value "Verify" -PassThru `
                                        | Add-Member -MemberType NoteProperty -Name value -Value $publicCertString
                if ([bool](Get-Member -InputObject $ADApplication -Name "keyCredentials"))
                {
                    [System.Collections.ArrayList]$keys = $ADApplication.keyCredentials
                    $keys.Add($credentialObject)
                    $ADApplication.keyCredentials = $keys
                }
                else
                {
                    $ADApplication | Add-Member -MemberType NoteProperty -Name keyCredentials -Value @($credentialObject)
                }
            }
            elseif($Delete -eq "True")
            {    
                $ADApplication.keyCredentials = $ADApplication.keyCredentials | Where-Object { 
                    [System.DateTime]::Parse($_.startDate).ToUniversalTime() -ne $NotBefore.ToUniversalTime() `
                    -and [System.DateTime]::Parse($_.endDate).ToUniversalTime() -ne $NotAfter.ToUniversalTime() `
                } 
            }
            elseif($Delete -eq "All")
            {
                $ADApplication.keyCredentials = @()
            }
            $finalCredsObject = $ADApplication | Select-Object -Property keyCredentials
            $body = ConvertTo-Json -InputObject $finalCredsObject 
            $operation = [string]::Empty;
            $requestUri = [string]::Empty;
            $GraphAPIAccessToken = Get-AzSKAccessToken -ResourceAppIdURI "https://graph.windows.net/";
            $operation = "PATCH";
            $requestUri = [string]::Format($GraphApiUrl, $ADApplication.objectId);
            $updateResult = Invoke-RestMethod `
                            -Method $operation `
                            -Uri $requestUri `
                            -Headers @{ Authorization = "Bearer " + $GraphAPIAccessToken } `
                            -ContentType "application/json" `
                            -Body $body `
                            -UseBasicParsing

            if($null -eq $updateResult)
            {
                 Throw "There was a problem while updating the service principal with new certificate"    
            }
    }

        static [PSObject] NewSelfSignedCertificate($AppName,$CertStartDate,$CertEndDate,$Provider)
        {
                $newCertificate = New-SelfSignedCertificate -DnsName $AppName `
                                                                    -Subject "CN=$AppName" `
                                                                    -CertStoreLocation Cert:\CurrentUser\My `
                                                                    -KeyExportPolicy Exportable `
                                                                    -NotBefore $CertStartDate `
                                                                    -NotAfter $CertEndDate `
                                                                    -Type DocumentEncryptionCert `
                                                                    -KeyUsage DataEncipherment `
                                                                    -KeySpec KeyExchange `
                                                                    -KeyUsageProperty Decrypt `
                                                                    -Provider $Provider `
                                                                    -ErrorAction Stop 
                return $newCertificate
        }
}