Flarum\Api\Controller\UploadLogoController::data PHP Method

    public function data(ServerRequestInterface $request, Document $document)
    {
        $this->assertAdmin($request->getAttribute('actor'));
        $file = array_get($request->getUploadedFiles(), 'logo');
        $tmpFile = tempnam($this->app->storagePath() . '/tmp', 'logo');
        $file->moveTo($tmpFile);
        $manager = new ImageManager();
        $encodedImage = $manager->make($tmpFile)->heighten(60, function ($constraint) {
            $constraint->upsize();
        })->encode('png');
        file_put_contents($tmpFile, $encodedImage);
        $mount = new MountManager(['source' => new Filesystem(new Local(pathinfo($tmpFile, PATHINFO_DIRNAME))), 'target' => new Filesystem(new Local($this->app->publicPath() . '/assets'))]);
        if (($path = $this->settings->get('logo_path')) && $mount->has($file = "target://{$path}")) {
            $mount->delete($file);
        }
        $uploadName = 'logo-' . Str::lower(Str::quickRandom(8)) . '.png';
        $mount->move('source://' . pathinfo($tmpFile, PATHINFO_BASENAME), "target://{$uploadName}");
        $this->settings->set('logo_path', $uploadName);
        return parent::data($request, $document);
    }