A new version of Node.js has been released. Version 15.1.0 offers, besides the usual bug fixes and other things, a new diagnostics channel feature.
In a diagnostics channel a developer can keep track of all events that take place within an application. This is done in a separate object, so that the performance remains as high as possible. If the diagnostics channel is not actively read, there should not be any noteworthy performance hit at all.
Developers can indicate in which situations an update should be sent to the diagnostics channel. These events can be anything. Node.js itself gives the communication with an sql-database as an example.
Other things the new feature can be used for is keeping track of network and filesystem activity and queries.
Michaël Zasso, a developer of Node.js, shows a complete overview of the possibilities of the diagnostics channel, together with several examples in a blog post.