BulkIndexRequest.ps1

begin { $JsonStrings = [Collections.Generic.List[String]]::new() }
    
process { 
    foreach ($Object in $InputObject) { 
        
        $IndexProperties = @{
            index = @{
                _index = $Index
                _type = $Type
                _id = $Id
            }
        }
        
        $IndexMarker = $IndexProperties | ConvertTo-Json -Compress
        $Document = $Object | ConvertTo-Json -Compress
        
        # Elastic bulk index format
        $JsonStrings.Add("$IndexMarker`n$Document`n") 
    } 
}

end { Write-Output (-join $JsonStrings) }