PHP Google Sheets API v4 - Working example to append rows with formatting

sheet_append_with_formatting.php

<?php

function append_rows_with_formatting($service, $sheet_id) {
    $cell = [
        'userEnteredFormat' => [
            'numberFormat' => [
                'type' => 'NUMBER',
                'pattern' => '[Color22]0.00', // '[Blue]#.##'
            ],
            "backgroundColor" => [
                "red" => 0.2,
                "green" => 1.0,
                "blue" => 0.5,
            ],
        ],
        'userEnteredValue' => [
            'numberValue' => 23
        ],
        'note' => 'previous value: 44'
    ];
    $cells = [ $cell, $cell ];
    $row = [
        'values' => $cells
    ];
    $rows[] = $row;

    $appendCellsRequest = [
        'fields' => '*',
        'rows' => $rows
    ];

    $request = [
        'appendCells' => $appendCellsRequest
    ];

    $batchUpdate = new Google_Service_Sheets_BatchUpdateSpreadsheetRequest([
        'requests' => [ $request ]
    ]);

    $service->spreadsheets->batchUpdate($sheet_id, $batchUpdate);
}