Vehicle XML Feed Generator

🧠 Overview

Once activated, the plugin automatically runs once a day (via WP-Cron) or whenever you click “Generate & Upload Now” in the admin panel. It does this:

1. Reads all posts from your WordPress database (wp_posts table).
2. Extracts required vehicle data fields (VIN, Make, Model, Year, Price, etc.).
3. Builds one XML file containing all vehicles.
4. Saves the XML file locally in the WordPress uploads folder.
5. Connects to your FTP server using credentials you set in the plugin settings.
6. Uploads the XML file to your FTP directory.

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⚙️ Step-by-Step How It Works

1️⃣ Query the Database

$posts = get_posts([
  'post_type' => ['listing','post','page'],
  'post_status' => 'publish',
  'numberposts' => -1,
]);

• This uses WordPress’s built-in get_posts() function, which reads directly from the wp_posts table in your database.
• You can change 'post_type' to match your actual vehicle listings (for example cars, inventory, stm_listings, etc.).
• Each returned $post object contains the same data as a DB row: ID, post_title, post_content, etc.

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2️⃣ Parse Each Post (Extract Vehicle Data)

For every post, the plugin runs through small helper functions to look for required information.

Examples:

VIN

function cgfe_extract_vin($text) {
  preg_match('/\b([A-HJ-NPR-Z0-9]{11,17})\b/i', $text, $m);
  return strtoupper($m[1] ?? '');
}

→ Looks inside the post content for a valid VIN pattern (17 characters, alphanumeric).

Price

preg_match('/\$\s*([0-9\.,]+)/', $text, $m);

→ Finds a price written like “$19,995”.

Year / Make / Model

list($make,$model,$trim) = cgfe_parse_title_for_make_model_trim($post->post_title);

→ Splits the title (e.g. “2017 Toyota Camry SE”) into Year, Make, Model, Trim.

Images

$images = cgfe_extract_image_urls_from_content($post->post_content);
$att = get_attached_media('image', $post->ID);

→ Finds all <img src="..."> tags inside the post HTML and also attached media in the WordPress library.

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3️⃣ Build the XML Document

A root <inventory> element is created with PHP’s SimpleXMLElement. For each post, a <vehicle> node is added and filled with child tags:

$vehicle = $xml->addChild('vehicle');
$vehicle->addChild('VIN', $vin);
$vehicle->addChild('Make', $make);
$vehicle->addChild('Model', $model);
...

The final XML looks like:

<inventory>
  <vehicle>
    <VIN>1HGCM82633A123456</VIN>
    <Make>Honda</Make>
    <Model>Accord</Model>
    <Year>2019</Year>
    <Trim>EX-L</Trim>
    <Price>15995</Price>
    <Mileage>45200 mi</Mileage>
    <ImageURLs>
      <Image>https://wordpress.com/wp-content/uploads/1.jpg</Image>
      <Image>https://wordpress.com/wp-content/uploads/2.jpg</Image>
    </ImageURLs>
    <ExteriorColor>Blue</ExteriorColor>
    <DealerComments>Well maintained, single owner.</DealerComments>
    <StockNumber>12345</StockNumber>
    <TransmissionType>Automatic</TransmissionType>
    <InstalledOptions>Leather Seats; Sunroof</InstalledOptions>
    <DealerID>DEALER123</DealerID>
    <DealerName>Quick Auto Sales</DealerName>
    ...
  </vehicle>
  ...
</inventory>

Then the XML is saved:

$xml->asXML($tmpfile);

That stores the file in /wp-content/uploads/cgfe_feed_YYYYMMDD_HHMMSS.xml.

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4️⃣ Upload via FTP

The plugin reads your FTP settings saved in WordPress options:

$ftp_host = get_option('cgfe_ftp_host');
$ftp_user = get_option('cgfe_ftp_user');
$ftp_pass = get_option('cgfe_ftp_pass');
$ftp_path = get_option('cgfe_ftp_path', '/');

Then it connects and uploads:

$conn = ftp_connect($ftp_host, 21, 10);
ftp_login($conn, $ftp_user, $ftp_pass);
ftp_pasv($conn, true);
ftp_put($conn, basename($localfile), $localfile, FTP_BINARY);
ftp_close($conn);

So it sends the generated XML file to your external FTP server every day automatically.

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5️⃣ WP-Cron Automation

When you activate the plugin:

register_activation_hook(__FILE__, 'cgfe_activate');

This schedules a daily job:

wp_schedule_event(time(), 'daily', 'cgfe_daily_event');

Every day, WordPress runs:

add_action('cgfe_daily_event', 'cgfe_generate_and_upload_feed');

That function repeats the steps above (read → parse → XML → FTP).

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6️⃣ Manual Run (Admin Page)

The plugin adds a menu called Car Feed Export in the WordPress admin dashboard. There’s a “Generate & Upload Now” button to manually trigger the process.

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🧩 Summary Flow

Step	Action	Function
1	Get all posts from wp_posts	get_posts()
2	Parse VIN, Make, Model, Year, etc.	regex & helper functions
3	Build XML document	SimpleXMLElement
4	Save XML to uploads folder	$xml->asXML()
5	Connect & upload to FTP	ftp_connect(), ftp_put()
6	Schedule daily cron	wp_schedule_event()