Event not fired when Full Page Cache is enabled in Magento 2

Question

I am trying to run a piece of code on every page load. I have the following

<config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:noNamespaceSchemaLocation="urn:magento:framework:Event/etc/events.xsd">
    <event name="controller_action_predispatch">
        <observer name="csp" instance="MyVendor\MyModule\Observers\MyObserver" shared="false" disabled="false" />
    </event>
</config>

This works besides from when Full Page Cache is enabled. When it is enabled my observer does not run.

Is there a better event I should watch to enable me to run code on every page load regardless of if Full Page Cache is turned on or off?

Answer 1

I am not sure if there is a better event for it but you could instead use a plugin.

The FPC plugs into \Magento\Framework\App\FrontControllerInterface::dispatch you could define a plugin in order to execute your method before the FPC kicks in.

The FPC plugin is defined here.