Cache Autowiring::buildServiceClasses into a transient

[mbmjertan]

Description

Using profiling we've gathered that we spend a lot of time in Autowiring::buildServiceClasses. In particular, we spent 14% of the whole page generation time just running the method for EightshiftForms.

Here's a screenshot from an Excimer-grabbed profile opened up in Speedscope on my local machine:

I added caching this into a transient using the project namespace as a unique key. This requires transients to be cleared on all deployments, and can cause breakage if manuallyDefinedDependencies is changed dynamically at runtime. This should probably be documented in eightshift-docs.

I should probably add a way to toggle this off. Do you prefer WP_ENVIRONMENT_TYPE, a special constant or both?

After this change, it's no longer noticeable in the profile and the whole registerServices method now takes less time than just the buildServiceClasses method used to:

I will open up additional PRs for optimization opportunities if I notice them.

[iruzevic]

Thank you for the implementation; it’s a great idea! However, I wouldn’t make it a requirement to clear transients each time you deploy a manual thing. We already have manifest caching in the transients, along with cache busting based on the project version number and other factors. Since the Cache class is loaded before the Main class, I believe you could utilize the Cache class to get and set your transients effectively.

[iruzevic]

I left a comment about cache busting

[mbmjertan]

Awesome, I wasn't familiar with how that class was implemented! ❤️
I will take a look and familiarize myself with the implementation and try to utilize that.

[iruzevic]

@mbmjertan and progress here, you need help?

[mbmjertan]

Hi, I didn't have the time to tackle this, hopefully I will today

[mbmjertan]

Refactored to use AbstractManifestCache and added basic support for caching custom objects in AbstractManifestCache (but maybe a generic concrete caching implementation in Libs would make sense in the future). Please test this before merging.

[iruzevic]

Looks like it is working. I will make a prerelease from develop branch for testing

[mbmjertan]

We deployed this onto staging with no issues