PHP Function to Export Products as CSV (without saving it in server)

ExportCSV.php

<?php

function exportCSV()
{
    // Define response headers for CSV download
    $headers = [
        "Content-type" => "text/csv",
        // Specifies the content type as CSV
        "Content-Disposition" => "attachment; filename=products.csv",
        // Instructs the browser to treat it as a downloadable attachment with the filename 'products.csv'
        "Pragma" => "no-cache",
        // Prevents caching by the browser
        "Cache-Control" => "must-revalidate, post-check=0, pre-check=0",
        // Further cache control to ensure content revalidation
        "Expires" => "0"
        // Sets the expiration date of the content to indicate it's already expired
    ];
    
    // Create a callback function for the response
    $callback = function () {

        // Open a writable stream to php://output (the browser)
        $file = fopen('php://output', 'w');

        // Write the header row to the CSV
        fputcsv($file, ['SKU', 'Name', 'Description', 'Price']);

        // Query the products in chunks of 100 records
        Product::chunk(100, function ($products) use ($file) {
            foreach ($products as $product) {
                
                // Write each product's data to the CSV
                fputcsv($file, [$product→sku, $product→name, $product->description, $product_price]);
            }
        });

        // Close the CSV file
        fclose($file);
    };

    // Create and return a response with the CSV data
    // this is how you don't have to save file into your server..
    return response()->stream($callback, 200, $headers);
}