Public share template

It is possible to override the default public share view. This is possible by implementing the IPublicShareTemplateProvider interface.

<?php
// lib/AppInfo/Application.php
namespace OCA\MyApp;

class Application extends App implements IBootstrap {
    ...

    public function register(IRegistrationContext $context): void {
        ...

        $context->registerPublicShareTemplateProvider(MyPublicShareTemplateProvider::class);
    }
}

<?php
// lib/providers/MyPublicShareTemplateProvider.php
namespace OCA\MyApp;

use OCA\MyApp\AppInfo\Application;
use OCP\AppFramework\Http\ContentSecurityPolicy;
use OCP\AppFramework\Http\Template\PublicTemplateResponse;
use OCP\AppFramework\Http\TemplateResponse;
use OCP\Defaults;
use OCP\IL10N;
use OCP\IURLGenerator;
use OCP\IUserManager;
use OCP\Share\IShare;
use OCP\Share\IPublicShareTemplateProvider;
use OCP\AppFramework\Services\IInitialState;
use OCP\Util;

class E2EEPublicShareTemplateProvider implements IPublicShareTemplateProvider {
    public function __construct(
        private IUserManager $userManager,
        private IUrlGenerator $urlGenerator,
        private IL10N $l10n,
        private Defaults $defaults,
        private IInitialState $initialState,
    ) {
    }

    public function shouldRespond(IShare $share): bool {
        $node = $share->getNode();
        return ...; // Whether your provider should be used or not.
    }

    public function renderPage(IShare $share, string $token, string $path): TemplateResponse {
        $shareNode = $share->getNode();
        $owner = $this->userManager->get($share->getShareOwner());

        $this->initialState->provideInitialState('fileId', $shareNode->getId());
        ...; // More initial state that you might need in your view.

        // OpenGraph Support: http://ogp.me/
        Util::addHeader('meta', [
            'property' => "og:title",
            'content' => $this->l10n->t("Encrypted share"),
        ]);
        Util::addHeader('meta', [
            'property' => "og:description",
            'content' => $this->defaults->getName()
                . ($this->defaults->getSlogan() !== '' ? ' - ' . $this->defaults->getSlogan() : ''),
        ]);
        Util::addHeader('meta', [
            'property' => "og:site_name",
            'content' => $this->defaults->getName(),
        ]);
        Util::addHeader('meta', [
            'property' => "og:url",
            'content' => $this->urlGenerator->linkToRouteAbsolute(
                'files_sharing.sharecontroller.showShare',
                ['token' => $token]
            ),
        ]);
        Util::addHeader('meta', [
            'property' => "og:type",
            'content' => "object",
        ]);

        $response = new PublicTemplateResponse(Application::APP_ID, 'myCustomTemplateFileName', []);
        $response->setHeaderTitle($this->l10n->t("My custom title"));

        $csp = new ContentSecurityPolicy();
        $csp->addAllowedFrameDomain('\'self\'');
        $response->setContentSecurityPolicy($csp);

        return $response;
    }
}