/opt/plesk/php/7.1/bin/php /usr/lib/plesk-9.0/composer.phar require api-platform/core ^2.0

Next follow thise instractions:

https://api-platform.com/docs/core/getting-started

First install DEV for the PHP you are using. In my case that would be PLESK PHP 7.1

apt-get install make gcc plesk-php71-dev

Next use PECL to install dbase extension.

/opt/plesk/php/7.1/bin/pecl install dbase-7.0.0beta1

If all goes good, you should see this:

Build process completed successfully

Installing '/opt/plesk/php/7.1/lib/php/modules/dbase.so'

install ok: channel://pecl.php.net/dbase-7.0.0beta1

configuration option "php_ini" is not set to php.ini location

You should add "extension=dbase.so" to php.ini

Last step is to register the extension:

echo "extension=dbase.so" > /opt/plesk/php/7.1/etc/php.d/dbase.ini

plesk bin php_handler --reread