Postmarkapp open tracking example in PHP

postmark_opened_email.php

<?php

// Define Postmark API endpoint, token
$baseEndpoint = "https://api.postmarkapp.com/messages/outbound/opens";
$serverToken = "YOUR_TOKEN"; // Replace with your actual server token

$headers = [
    "Accept: application/json",
    "X-Postmark-Server-Token: $serverToken"
];

$offset = 0;
$count = 500;  // Maximum allowed by Postmark API
$results = [];
$totalCount = 0;

do {
    // Set up the parameters for your query
    $params = [
        "count"  => $count,
        "offset" => $offset
    ];

    // Construct the full endpoint with parameters
    $endpoint = $baseEndpoint . "?" . http_build_query($params);

    // Set up the cURL request
    $ch = curl_init($endpoint);
    curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
    curl_setopt($ch, CURLOPT_HTTPHEADER, $headers);
    curl_setopt($ch, CURLOPT_CUSTOMREQUEST, "GET");

    // Execute the request
    $response = curl_exec($ch);

    // Error handling
    if (curl_errno($ch)) {
        echo 'Error:' . curl_error($ch);
        exit;
    }

    // Parse the response
    $data = json_decode($response);

    // Check the total count
    if (!$totalCount) {
        $totalCount = $data->TotalCount;
    }

    // Extract the required data and group by MessageStream
    foreach ($data->Opens as $open) {
        $key = $open->MessageStream;

        $results[$key][] = [
            'MessageID' => $open->MessageID,
            'MessageStream' => $open->MessageStream,
            'Recipient' => $open->Recipient
        ];
    }

    $offset += $count;

} while ($offset < $totalCount);

// Close the cURL session
curl_close($ch);

// Output the grouped results
echo json_encode($results, JSON_PRETTY_PRINT);

?>