count events on remote calendars

src/Bundle/ChillCalendarBundle/Controller/RemoteCalendarProxyController.php

@@ -69,11 +69,30 @@ class RemoteCalendarProxyController
             throw new BadRequestHttpException('dateTo not parsable');
         }
 
-        $events = $this->remoteCalendarConnector->listEventsForUser($user, $dateFrom, $dateTo);
-        $paginator = $this->paginatorFactory->create(count($events));
+        $total = $this->remoteCalendarConnector->countEventsForUser($user, $dateFrom, $dateTo);
+        $paginator = $this->paginatorFactory->create($total);
 
-        if (count($events) > 0) {
-            $paginator->setItemsPerPage($paginator->getTotalItems());
+        if (0 === $total) {
+            return new JsonResponse(
+                $this->serializer->serialize(new Collection([], $paginator), 'json'),
+                JsonResponse::HTTP_OK,
+                [],
+                true
+            );
+        }
+
+        $events = $this->remoteCalendarConnector->listEventsForUser(
+            $user,
+            $dateFrom,
+            $dateTo,
+            $paginator->getCurrentPageFirstItemNumber(),
+            $paginator->getItemsPerPage()
+        );
+
+        // in some case, we cannot paginate: we have to fetch all the items at once. We must avoid
+        // further requests by forcing the number of items returned.
+        if (count($events) > $paginator->getItemsPerPage()) {
+            $paginator->setItemsPerPage(count($events));
         }
 
         $collection = new Collection($events, $paginator);

src/Bundle/ChillCalendarBundle/RemoteCalendar/Connector/MSGraphRemoteCalendarConnector.php

@@ -29,10 +29,13 @@ use Symfony\Component\HttpFoundation\Response;
 use Symfony\Component\Routing\Generator\UrlGeneratorInterface;
 use Symfony\Contracts\HttpClient\Exception\ClientExceptionInterface;
 use Symfony\Contracts\Translation\TranslatorInterface;
+use function array_key_exists;
 use function count;
 
 class MSGraphRemoteCalendarConnector implements RemoteCalendarConnectorInterface
 {
+    private array $cacheScheduleTimeForUser = [];
+
     private CalendarRangeRepository $calendarRangeRepository;
 
     private LoggerInterface $logger;
@@ -73,6 +76,43 @@ class MSGraphRemoteCalendarConnector implements RemoteCalendarConnectorInterface
         $this->userHttpClient = $userHttpClient;
     }
 
+    public function countEventsForUser(User $user, DateTimeImmutable $startDate, DateTimeImmutable $endDate): int
+    {
+        $userId = $this->mapCalendarToUser->getUserId($user);
+
+        if (null === $userId) {
+            return 0;
+        }
+
+        try {
+            $data = $this->userHttpClient->request(
+                'GET',
+                'users/' . $userId . '/calendarView',
+                [
+                    'query' => [
+                        'startDateTime' => $startDate->format(DateTimeImmutable::ATOM),
+                        'endDateTime' => $endDate->format(DateTimeImmutable::ATOM),
+                        '$count' => 'true',
+                        '$top' => 0,
+                    ],
+                ]
+            )->toArray();
+        } catch (ClientExceptionInterface $e) {
+            if (403 === $e->getResponse()->getStatusCode()) {
+                return count($this->getScheduleTimesForUser($user, $startDate, $endDate));
+            }
+
+            $this->logger->error('Could not get list of event on MSGraph', [
+                'error_code' => $e->getResponse()->getStatusCode(),
+                'error' => $e->getResponse()->getInfo(),
+            ]);
+
+            return 0;
+        }
+
+        return $data['@odata.count'];
+    }
+
     public function getMakeReadyResponse(string $returnPath): Response
     {
         return new RedirectResponse($this->urlGenerator
@@ -84,7 +124,15 @@ class MSGraphRemoteCalendarConnector implements RemoteCalendarConnectorInterface
         return $this->tokenStorage->hasToken();
     }
 
-    public function listEventsForUser(User $user, DateTimeImmutable $startDate, DateTimeImmutable $endDate): array
+    /**
+     * @throws \Symfony\Contracts\HttpClient\Exception\DecodingExceptionInterface
+     * @throws \Symfony\Contracts\HttpClient\Exception\RedirectionExceptionInterface
+     * @throws \Symfony\Contracts\HttpClient\Exception\ServerExceptionInterface
+     * @throws \Symfony\Contracts\HttpClient\Exception\TransportExceptionInterface
+     *
+     * @return array|\Chill\CalendarBundle\RemoteCalendar\Model\RemoteEvent[]
+     */
+    public function listEventsForUser(User $user, DateTimeImmutable $startDate, DateTimeImmutable $endDate, ?int $offset = 0, ?int $limit = 50): array
     {
         $userId = $this->mapCalendarToUser->getUserId($user);
 
@@ -101,6 +149,8 @@ class MSGraphRemoteCalendarConnector implements RemoteCalendarConnectorInterface
                         'startDateTime' => $startDate->format(DateTimeImmutable::ATOM),
                         'endDateTime' => $endDate->format(DateTimeImmutable::ATOM),
                         '$select' => 'id,subject,start,end,isAllDay',
+                        '$top' => $limit,
+                        '$skip' => $offset,
                     ],
                 ]
             )->toArray();
@@ -127,7 +177,7 @@ class MSGraphRemoteCalendarConnector implements RemoteCalendarConnectorInterface
                 return $this->getScheduleTimesForUser($user, $startDate, $endDate);
             }
 
-            $this->logger->debug('Could not get list of event on MSGraph', [
+            $this->logger->error('Could not get list of event on MSGraph', [
                 'error_code' => $e->getResponse()->getStatusCode(),
                 'error' => $e->getResponse()->getInfo(),
             ]);
@@ -475,6 +525,10 @@ class MSGraphRemoteCalendarConnector implements RemoteCalendarConnectorInterface
     {
         $userId = $this->mapCalendarToUser->getUserId($user);
 
+        if (array_key_exists($userId, $this->cacheScheduleTimeForUser)) {
+            return $this->cacheScheduleTimeForUser[$userId];
+        }
+
         if (null === $userId) {
             return [];
         }
@@ -508,12 +562,14 @@ class MSGraphRemoteCalendarConnector implements RemoteCalendarConnectorInterface
             return [];
         }
 
-        return array_map(
+        $this->cacheScheduleTimeForUser[$userId] = array_map(
             function ($item) {
                 return $this->remoteEventConverter->convertAvailabilityToRemoteEvent($item);
             },
             $response['value'][0]['scheduleItems']
         );
+
+        return $this->cacheScheduleTimeForUser[$userId];
     }
 
     private function patchCalendarOnRemote(Calendar $calendar, array $newInvites): void

src/Bundle/ChillCalendarBundle/RemoteCalendar/Connector/NullRemoteCalendarConnector.php

@@ -21,6 +21,11 @@ use Symfony\Component\HttpFoundation\Response;
 
 class NullRemoteCalendarConnector implements RemoteCalendarConnectorInterface
 {
+    public function countEventsForUser(User $user, DateTimeImmutable $startDate, DateTimeImmutable $endDate): int
+    {
+        return 0;
+    }
+
     public function getMakeReadyResponse(string $returnPath): Response
     {
         throw new LogicException('As this connector is always ready, this method should not be called');
@@ -31,7 +36,7 @@ class NullRemoteCalendarConnector implements RemoteCalendarConnectorInterface
         return true;
     }
 
-    public function listEventsForUser(User $user, DateTimeImmutable $startDate, DateTimeImmutable $endDate): array
+    public function listEventsForUser(User $user, DateTimeImmutable $startDate, DateTimeImmutable $endDate, ?int $offset = 0, ?int $limit = 50): array
     {
         return [];
     }

src/Bundle/ChillCalendarBundle/RemoteCalendar/Connector/RemoteCalendarConnectorInterface.php

@@ -21,6 +21,8 @@ use Symfony\Component\HttpFoundation\Response;
 
 interface RemoteCalendarConnectorInterface
 {
+    public function countEventsForUser(User $user, DateTimeImmutable $startDate, DateTimeImmutable $endDate): int;
+
     /**
      * Return a response, more probably a RedirectResponse, where the user
      * will be able to fullfill requirements to prepare this connector and
@@ -37,7 +39,7 @@ interface RemoteCalendarConnectorInterface
     /**
      * @return array|RemoteEvent[]
      */
-    public function listEventsForUser(User $user, DateTimeImmutable $startDate, DateTimeImmutable $endDate): array;
+    public function listEventsForUser(User $user, DateTimeImmutable $startDate, DateTimeImmutable $endDate, ?int $offset = 0, ?int $limit = 50): array;
 
     public function removeCalendar(string $remoteId, array $remoteAttributes, User $user, ?CalendarRange $associatedCalendarRange = null): void;