feat(database): ✨ add completely new analytics backend

www/src/setup/analytics.php

@@ -0,0 +1,66 @@
+<?php
+
+$data_time_start = microtime(true);
+
+$analytics_enable_tail = false;
+$analytics_post = null;
+
+function deduce_user_agent() {
+    $real_agent=$_SERVER['HTTP_USER_AGENT'];
+
+    if(preg_match('/(Googlebot|\w*Google\w*)/', $real_agent, $match)) {
+        return "bot/google/" . $match[1];
+    }
+    elseif(preg_match('/(Mozilla|Chrome|Chromium)/', $real_agent, $match)) {
+        return "user/" . $match[1];
+    }
+    else {
+        return "unidentified";
+    }
+}
+
+function analytics_is_user() {
+    return preg_match('/^user/', deduce_user_agent());
+}
+
+register_shutdown_function(function() {
+    $data_end_time = microtime(true);
+
+    global $data_time_start;
+    global $analytics_adapter;
+
+    global $REQUEST_PATH;
+    global $REQUEST_QUERY;
+
+    global $analytics_enable_tail;
+
+    $data_time_end = microtime(true);
+
+    $http_referer = 'magic';
+    if(isset($_SERVER['HTTP_REFERER'])) {
+        $http_referer = parse_url($_SERVER['HTTP_REFERER'], PHP_URL_HOST);
+    }
+
+    $referrer = $REQUEST_QUERY['referer'] ?? $REQUEST_QUERY['ref'] ?? $http_referer;
+
+    $compute_time = $data_time_end - $data_time_start;
+
+    $analytics_adapter->log_path_access($REQUEST_PATH,
+        deduce_user_agent(),
+        $referrer,
+        $compute_time);
+
+    if($analytics_enable_tail) {
+        echo "<!-- Total page time was: " . $compute_time . " -->";
+    }
+
+    if(isset($analytics_post)) {
+        $analytics_post->increment_counter("compute_time", $compute_time);
+
+        if(analytics_is_user()) {
+            $analytics_post->increment_counter("views");
+        }
+    }
+});
+
+?>