GraphQL: Entries relatedTo CalendarEvent

[Aku-benj]

What is your idea?

Hi,
I am working on a project where Events are related to Entries through field selector

I have a listing page that fetch Calendar Events with some filters. Those filters are the ones related to my events only.
It doesnt seem to be possible via Graphql with the current flow to filter entries on related Events via relatedToEntries argument. Calendar Event are not really an entry section so we can't benefit of the relatedToEntries on other entry sections.

So I wanted to share with others my current way to work around that.
Maybe it could directly be implemented in the plugin with a bit of documentation.

What I want :

What I am trying to do (get the list of "lieux"|entries related to events of my calendar) :

{
  lieuxStructureEntries(
    site: "en"
    relatedToEntries: {
      section: "calendarEvent" <-- do not exist
      site: "en",
      loadOccurrences: false,
      calendarId: 4
    }
  ) {
    ... on lieuStructure_Entry {
      title
    }
  }
}

What I ended up doing :

{
  lieuxStructureEntries(
    site: "en"
    relatedToCalendarEvents: { <-- see below for code
      site: "en",
      loadOccurrences: false,
      calendarId: 4
    }
  ) {
    ... on lieuStructure_Entry {
      title
    }
  }
}

How ? #

1. Via a module or plugin :

• Register a custom GQL Argument Handler :

        Event::on(
            ArgumentManager::class,
            ArgumentManager::EVENT_DEFINE_GQL_ARGUMENT_HANDLERS,
            function(RegisterGqlArgumentHandlersEvent $event) {
                $event->handlers['relatedToCalendarEvents'] = RelatedCalendarEvents::class;
            }
        );

• Add a custom argument to all queries that could benefit from it :

        Event::on(
            Gql::class,
            Gql::EVENT_REGISTER_GQL_QUERIES,
            function(RegisterGqlQueriesEvent $event) {
                $relatedToCalendarEventsArgs = [
                    'relatedToCalendarEvents' => [
                        'name' => 'relatedToCalendarEvents',
                        'type' => Type::listOf(CalendarEventRelation::getType()),
                        'description' => 'Narrows the query results to elements that relate to a Calendar Event list defined with this argument.',
                    ],
                ];

                // Maybe find a better way to add custom argument directly inside craft\gql\base\ElementArguments
                foreach ($event->queries as $queryName => $query) {
                    if ($queryName == 'entries' || str_ends_with($queryName, 'Entries')) {
                        $event->queries[$queryName]['args'] = array_merge(
                            $event->queries[$queryName]['args'],
                            $relatedToCalendarEventsArgs
                        );
                    }
                }
            }
        );

2. Create the new Gql Type for the Relation that utilize the existing Solspace\Calendar\Bundles\GraphQL\Arguments\EventArguments :

class CalendarEventRelation extends InputObjectType
{
    /**
     * @return mixed
     */
    public static function getType(): mixed
    {
        $typeName = 'CalendarEventRelationCriteriaInput';

        return GqlEntityRegistry::getOrCreate($typeName, fn() => new InputObjectType([
            'name' => $typeName,
            'fields' => fn() => [
                ...EventArguments::getArguments(),
            ],
        ]));
    }
}

3. Finally define the RelatedCalendarEvents argument Handler using Solspace\Calendar\Elements\Event:

class RelatedCalendarEvents extends RelationArgumentHandler
{
    protected string $argumentName = 'relatedToCalendarEvents';

    /**
     * @inheritdoc
     */
    protected function handleArgument($argumentValue): mixed
    {
        $calendarUids = GqlPermissions::allowedCalendarUids();

        if ($calendarUids) {
            $argumentValue = array_map(function ($value) use ($calendarUids) {
                $value['calendarUid'] = $calendarUids;
                return $value;
            }, $argumentValue);
        }

        $argumentValue = parent::handleArgument($argumentValue);
        return $this->getIds(Event::class, $argumentValue);
    }
}

Final result :

Calendar Version

5.x

Craft Version

5.x

[Aku-benj]

For reference, since 5.9 it is now possible to register custom argument directly in craft\gql\base\ElementArguments using EVENT_DEFINE_ARGUMENTS : craftcms/cms@0ee5f48

I will try to update the code above shortly.