Cannot Use class files with my existing project

[TNChalise]

I have done with all installation prerequisites. I have now currently loadedmosquitto.so extension in my php.ini. But, I can use:
$client = new \Mosquitto\Client();
But cant:
$base = new \EventBase();
Is there anything, I have to do to remove fatal error of

Class 'EventBase' not found.

Any help will be appreciated.

I have executed in cli mode.

[indigator]

You need to install php libevent extension using pecl to use EventBase.
This extension is however not compatible with php 7.