Bulk change PowerBI Datasets to new source

PowerBIDataSourceChange.ps1

# Insert AAD Client ID below
$clientId = "Insert Azure AD Application Client ID In Here." 

# Calls the Active Directory Authentication Library (ADAL) to authenticate against AAD
function GetAuthToken
{
    if(-not (Get-Module AzureRm.Profile)) {
      Import-Module AzureRm.Profile
    }
    $redirectUri = "urn:ietf:wg:oauth:2.0:oob"
    $resourceAppIdURI = "https://analysis.windows.net/powerbi/api"
    $authority = "https://login.microsoftonline.com/common/oauth2/authorize";
    $authContext = New-Object "Microsoft.IdentityModel.Clients.ActiveDirectory.AuthenticationContext" -ArgumentList $authority
    $authResult = $authContext.AcquireToken($resourceAppIdURI, $clientId, $redirectUri, "Auto")
    return $authResult
}

# PART 1: Authentication
# ==================================================================
$token = GetAuthToken

Add-Type -AssemblyName System.Net.Http
$temp_path_root = "$PSScriptRoot\pbi-copy-workspace-temp-storage"

# Building Rest API header with authorization token
$auth_header = @{
   'Content-Type'='application/json'
   'Authorization'=$token.CreateAuthorizationHeader()
}

# Import Spreadsheet detailing Workspaces and Dataset names etc.
$src = Import-CSV "c:\temp\datasets2.csv"

# For each line in the Spreadsheet build the JSON File.
foreach ($line in $src) {
    $SubmitURL = "https://api.powerbi.com/v1.0/myorg/groups/$($line.WorkSpaceID)/datasets/$($line.DatasetID)/Default.UpdateDataSources"
    $obj = [PSCustomObject]@{"updateDetails" = @(@{"datasourceSelector" = @{"datasourceType" = "AnalysisServices"; "connectionDetails" = @{"server" = $($line.serverOLD); "database" = $($line.databaseold)}}; "connectionDetails" = @{"server" = $($line.serverNEW); "database" = $($line.databaseNEW)}})} 
    $JSON = $obj | ConvertTo-JSON -Depth 10
    
    # Comment out the lines below once testing complete
    Write-Host $JSON
    Write-Host "URL to be Used: $SubmitURL"
    
    # Uncomment the line below when ready to post to the REST API
    #Invoke-WebRequest -Uri $SubmitURL -Method POST -Body $JSON
}