feat: Soft Navigations trial

[cwli24]

Introducing a lighter and simplified version of the existing spa feature that tracks soft navigations. This new feature still sends BrowserInteraction events, but the duration and finishing of those interactions have been redefined. As a replacement, it ought to reduce complexity and integration issues around the existing spa and exhibit better and faster performance.

Overview

Soft navigations feature is disabled unless the soft-nav feature flag is passed into the init configuration, in which case soft nav will replace the old spa on the page. This feature captures "interactions" based on the following sequences in exact chronological order:

1. click, keydown, or submit event on the page occurs
   a. an interaction can also be started through the newrelic.interaction() api
2. the location (url) of the page is altered
3. there's a dom change noticed by MutationObserver

No ensuing single or chained callbacks, network requests, async timers, etc. are tracked, and they do not affect the length of the interaction, unlike the old spa method. The createTracer spa api will have no effect on soft nav, though the other spa apis remain the same.

Related Issue(s)

Building on #626
Angler: https://source.datanerd.us/agents/angler/pull/529

Testing

Jest & wdio tests for feature added based on this google doc

[github-actions]

Last ran on March 12, 2024 14:22:41 CDT
Checking merge of (3dac1f7) into main (dfdbaab)

[EduardDopler]

Any plans to pull only either the old or the new implementation into the browser? Currently, both are part of the spa build. Hence the significant increase in size.

[patrickhousley]

Any plans to pull only either the old or the new implementation into the browser? Currently, both are part of the spa build. Hence the significant increase in size.

It is not possible in our current deployment mechanics. Our plans are to eventually remove the old SPA feature completely which will reduce the bundle size. In the mean time, the NPM package allows customers to build their own customized agent with the features they care about.