function Publish-ImportRDLFile 
{
    param
    (
        [string]$RdlFilePath,
        [string]$GroupId,
        [string]$nameConflict = "Abort"
    )

    # Get file content and create body
    $fileName = [IO.Path]::GetFileName($RdlFilePath)
    $boundary = [guid]::NewGuid().ToString()
    $fileBody = Get-Content -Path $RdlFilePath -Encoding UTF8

    $body = @"
---------FormBoundary$boundary
Content-Disposition: form-data; name="$filename"; filename="$filename"
Content-Type: application/rdl

$fileBody 
---------FormBoundary$boundary--

"@

    # Get AccessToken and set it as header.
    $headers = Get-PowerBIAccessToken

    if ($GroupId) {
        $url = "https://api.powerbi.com/v1.0/myorg/groups/$GroupId/imports?datasetDisplayName=$fileName&nameConflict=$nameConflict"
    }
    else {
        $url = "https://api.powerbi.com/v1.0/myorg/imports?datasetDisplayName=$fileName&nameConflict=$nameConflict"
    }

    # Create import
    $report = Invoke-RestMethod -Uri $url -Method Post -Headers $headers -Body $body -ContentType "multipart/form-data"   
    $report.id
}

function Set-BasicPassword-To-RDL 
{
    param
    (
        [string]$Id,
        [string]$GroupId,
        [string]$UserName,
        [string]$Password
    )

    # Get AccessToken and set it as header.
    $headers = Get-PowerBIAccessToken

    # Get import result first. As it may take a bit of time until report is created, so repeat until I can get report Id
    $reportId = $null
    while($reportId -eq $null)
    {
        if ($GroupId) {
            $url = "https://api.powerbi.com/v1.0/myorg/groups/$GroupId/imports/$Id"
        }
        else {
            $url = "https://api.powerbi.com/v1.0/myorg/imports/$Id"
        }

        $import = Invoke-RestMethod -Uri $url -Method Get -Headers $headers
        $reportId = $import.reports.id
    }

    # Datasource information
    if ($GroupId) {
        $url = "https://api.powerbi.com/v1.0/myorg/groups/$GroupId/reports/$reportId/datasources"
    }
    else {
        $url = "https://api.powerbi.com/v1.0/myorg/reports/$reportId/datasources"
    }

    $datasources = Invoke-RestMethod -Uri $url -Method Get -Headers $headers
    $gatewayId = $datasources.value[0].gatewayId
    $datasourceId = $datasources.value[0].datasourceId

    # Finallly set credential. No Uri difference between myworkspace and group workspace.
    $url = "https://api.powerbi.com/v1.0/myorg/gateways/$gatewayId/datasources/$datasourceId"

    # This is a sample for basic authentication. Find more samples at https://docs.microsoft.com/en-us/rest/api/power-bi/gateways/updatedatasource#examples
    $body = @"
{
  "credentialDetails": {
    "credentialType":"Basic",
    "credentials": "{\"credentialData\":[{\"name\":\"username\", \"value\":\"$UserName\"},{\"name\":\"password\", \"value\":\"$Password\"}]}",
    "encryptedConnection": "Encrypted",
    "encryptionAlgorithm": "None",
    "privacyLevel": "None"
    }
}
"@
    $datasources = Invoke-RestMethod -Uri $url -Method Patch -Headers $headers -ContentType "application/json" -Body $body
}

# Connect to Power BI.
Connect-PowerBIServiceAccount

$groupId = "<group id>"
# Create Import
$id = Publish-ImportRDLFile -GroupId $groupId -RdlFilePath "<path to rdl file>"
# Set password
Set-BasicPassword-To-RDL -Id $id -GroupId $groupId -UserName "<username>" -Password "<password>"