Grafana Graph PHP Proxy

grafana_graph.php

<?php

// Change to your LAN IP subnet
preg_match('/^192\.168\.0\.\d{1,3}$/', $_SERVER['REMOTE_ADDR'], $output);

if (!$output) {
    die('Access denied');
}

/* To generate bearer, go to Grafana confiration page, select API Keys and create Viewer API Key */
$bearer = '<YOUR GRAFANA API KEY>';

/* Example: https://<grafana_url>/render/d-solo/blablabla/dashboard */
$base_url = '<GRAFANA DASHBOARD URL>';

/* Download Image Magician from https://github.com/Oberto/php-image-magician/blob/master/php_image_magician.php */
include('includes/php_image_magician.php');

$w = (int) $_GET['w'] ?? false;
$h = (int) $_GET['h'] ?? false;

if (!empty($_GET['w'])) { unset($_GET['w']); }
if (!empty($_GET['h'])) { unset($_GET['h']); }

$query = http_build_query($_GET);
$url = "{$base_url}?{$query}";

$ch = curl_init();
curl_setopt($ch, CURLOPT_URL, $url);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, 1);
curl_setopt($ch, CURLOPT_FOLLOWLOCATION, 1);
curl_setopt($ch, CURLOPT_HTTPHEADER, [
    "Authorization: Bearer {$bearer}"
]);

$response = curl_exec($ch);
$content_type = curl_getinfo($ch, CURLINFO_CONTENT_TYPE);
$content_length = curl_getinfo($ch, CURLINFO_CONTENT_LENGTH_DOWNLOAD);

curl_close($ch);

$image_types = ['image/png', 'image/jpg'];

if (!in_array($content_type, $image_types)) {
    echo $response;
    die();
}

$ext = explode('/', $content_type)[1];
$tmp_file = sys_get_temp_dir() . '/' . 'dash' . '.' . md5(time()) . '.' . $ext;
file_put_contents($tmp_file, $response);

if ($w && $h) {
    $imageLib = new imageLib($tmp_file);
    $imageLib->resizeImage($w, $h, 0);
    $imageLib->saveImage($tmp_file, 100);
    $content_lenght = filesize($tmp_file);
}

header("Content-type: {$content_type}");
//header("Content-length: {$content_length}");

echo file_get_contents($tmp_file);
unlink($tmp_file);