Add combined deployment health check

docker-compose.yml

@@ -16,6 +16,12 @@ services:
     depends_on:
       db:
         condition: service_healthy
+    healthcheck:
+      test: ["CMD-SHELL", "php /var/www/html/health.php --check"]
+      interval: 10s
+      timeout: 5s
+      retries: 10
+      start_period: 30s
 
   db:
     image: mariadb:11.4

health.php

@@ -0,0 +1,68 @@
+<?php
+
+mysqli_report(MYSQLI_REPORT_OFF);
+
+function env_value(string $name, string $default = ''): string
+{
+    $value = getenv($name);
+    return $value === false ? $default : $value;
+}
+
+function check_database(string $label, string $database, ?string $user = null, ?string $password = null): array
+{
+    $host = env_value('DB_HOST', 'localhost');
+    $port = (int)env_value('DB_PORT', '3307');
+    $username = $user ?? env_value('DB_USER', 'root');
+    $dbPassword = $password ?? env_value('DB_PASS', '');
+
+    $connection = @new mysqli($host, $username, $dbPassword, $database, $port);
+
+    if ($connection->connect_error) {
+        error_log("Health check database failed ({$label}): " . $connection->connect_error);
+        return [
+            'name' => $label,
+            'status' => 'error',
+        ];
+    }
+
+    $ok = $connection->query('SELECT 1') !== false;
+    if (!$ok) {
+        error_log("Health check query failed ({$label}): " . $connection->error);
+    }
+
+    $connection->close();
+
+    return [
+        'name' => $label,
+        'status' => $ok ? 'ok' : 'error',
+    ];
+}
+
+$project01User = env_value('APP_DB_USER') ?: env_value('DB_USER', 'root');
+$project01Pass = env_value('APP_DB_PASSWORD') ?: env_value('DB_PASS', '');
+
+$checks = [
+    check_database('project_01', env_value('DB_01_NAME', 'db_webgis_01'), $project01User, $project01Pass),
+    check_database('poverty_mapping', env_value('DB_WEBGIS_NAME', 'db_webgis')),
+];
+
+$healthy = true;
+foreach ($checks as $check) {
+    if ($check['status'] !== 'ok') {
+        $healthy = false;
+        break;
+    }
+}
+
+http_response_code($healthy ? 200 : 500);
+header('Content-Type: application/json; charset=utf-8');
+
+echo json_encode([
+    'status' => $healthy ? 'ok' : 'error',
+    'checks' => $checks,
+], JSON_UNESCAPED_SLASHES);
+
+if (PHP_SAPI === 'cli') {
+    echo PHP_EOL;
+    exit($healthy ? 0 : 1);
+}