perf(statistics): rewrite for performance on very large communities (#3531)

Co-authored-by: Sami Mazouz <ilyasmazouz@gmail.com>

extensions/statistics/src/Api/Controller/ShowStatisticsData.php

@@ -0,0 +1,155 @@
+<?php
+
+/*
+ * This file is part of Flarum.
+ *
+ * For detailed copyright and license information, please view the
+ * LICENSE file that was distributed with this source code.
+ */
+
+namespace Flarum\Statistics\Api\Controller;
+
+use DateTime;
+use DateTimeZone;
+use Flarum\Discussion\Discussion;
+use Flarum\Http\RequestUtil;
+use Flarum\Post\Post;
+use Flarum\Post\RegisteredTypesScope;
+use Flarum\Settings\SettingsRepositoryInterface;
+use Flarum\User\User;
+use Illuminate\Contracts\Cache\Repository as CacheRepository;
+use Illuminate\Database\Eloquent\Builder;
+use Illuminate\Support\Arr;
+use Laminas\Diactoros\Response\JsonResponse;
+use Psr\Http\Message\ResponseInterface;
+use Psr\Http\Message\ServerRequestInterface;
+use Psr\Http\Server\RequestHandlerInterface;
+
+class ShowStatisticsData implements RequestHandlerInterface
+{
+    /**
+     * The amount of time to cache lifetime statistics data for in seconds.
+     */
+    public static $lifetimeStatsCacheTtl = 300;
+
+    /**
+     * The amount of time to cache timed statistics data for in seconds.
+     */
+    public static $timedStatsCacheTtl = 900;
+
+    protected $entities = [];
+
+    /**
+     * @var SettingsRepositoryInterface
+     */
+    protected $settings;
+
+    /**
+     * @var CacheRepository
+     */
+    protected $cache;
+
+    public function __construct(SettingsRepositoryInterface $settings, CacheRepository $cache)
+    {
+        $this->settings = $settings;
+        $this->cache = $cache;
+
+        $this->entities = [
+            'users' => [User::query(), 'joined_at'],
+            'discussions' => [Discussion::query(), 'created_at'],
+            'posts' => [Post::where('type', 'comment')->withoutGlobalScope(RegisteredTypesScope::class), 'created_at']
+        ];
+    }
+
+    public function handle(ServerRequestInterface $request): ResponseInterface
+    {
+        $actor = RequestUtil::getActor($request);
+
+        // Must be an admin to get statistics data -- this is only visible on the admin
+        // control panel.
+        $actor->assertAdmin();
+
+        $reportingPeriod = Arr::get($request->getQueryParams(), 'period');
+
+        return new JsonResponse($this->getResponse($reportingPeriod));
+    }
+
+    private function getResponse(?string $period): array
+    {
+        if ($period === 'lifetime') {
+            return $this->getLifetimeStatistics();
+        }
+
+        return array_merge(
+            $this->getTimedStatistics(),
+            ['timezoneOffset' => $this->getUserTimezone()->getOffset(new DateTime)]
+        );
+    }
+
+    private function getLifetimeStatistics()
+    {
+        return $this->cache->remember('flarum-subscriptions.lifetime_stats', self::$lifetimeStatsCacheTtl, function () {
+            return array_map(function ($entity) {
+                return $entity[0]->count();
+            }, $this->entities);
+        });
+    }
+
+    private function getTimedStatistics()
+    {
+        return $this->cache->remember('flarum-subscriptions.timed_stats', self::$lifetimeStatsCacheTtl, function () {
+            return array_map(function ($entity) {
+                return $this->getTimedCounts($entity[0], $entity[1]);
+            }, $this->entities);
+        });
+    }
+
+    private function getTimedCounts(Builder $query, $column)
+    {
+        // Calculate the offset between the server timezone (which is used for
+        // dates stored in the database) and the user's timezone (set via the
+        // settings table). We will use this to make sure we aggregate the
+        // daily/hourly statistics according to the user's timezone.
+        $offset = $this->getTimezoneOffset();
+
+        $results = $query
+            ->selectRaw(
+                'DATE_FORMAT(
+                    @date := DATE_ADD('.$column.', INTERVAL ? SECOND), -- convert to user timezone
+                    IF(@date > ?, \'%Y-%m-%d %H:00:00\', \'%Y-%m-%d\') -- if within the last 24 hours, group by hour
+                ) as time_group',
+                [$offset, new DateTime('-25 hours')]
+            )
+            ->selectRaw('COUNT(id) as count')
+            ->where($column, '>', new DateTime('-365 days'))
+            ->groupBy('time_group')
+            ->pluck('count', 'time_group');
+
+        // Now that we have the aggregated statistics, convert each time group
+        // into a UNIX timestamp.
+        $userTimezone = $this->getUserTimezone();
+
+        $timed = [];
+
+        $results->each(function ($count, $time) use (&$timed, $userTimezone) {
+            $time = new DateTime($time, $userTimezone);
+            $timed[$time->getTimestamp()] = (int) $count;
+        });
+
+        return $timed;
+    }
+
+    private function getTimezoneOffset()
+    {
+        $now = new DateTime;
+
+        $dataTimezone = new DateTimeZone(date_default_timezone_get());
+
+        return $this->getUserTimezone()->getOffset($now) - $dataTimezone->getOffset($now);
+    }
+
+    private function getUserTimezone()
+    {
+        return new DateTimeZone($this->settings->get('flarum-statistics.timezone', date_default_timezone_get()));
+    }
+}