[Task] Add "test connection" button to Custom Target creation modal

[andrewazores]

As a user, when I'm defining a new custom target it would be useful to be able to verify that the connection URL I've entered is correct by having a "test connection" button that I can click before actually pressing "Submit". Right now, the only way to do this is by creating the custom target definition and then going to a view like Recordings to see if I'm able to retrieve and view the Active Recordings. If I entered the URL wrong I then have to delete the custom target, create a new one, and try again. Having a "test connection" button would drastically shorten that feedback loop and help catch input errors sooner.

[tthvo]

@andrewazores I am wondering why endpoint for creating custom target is not accepting labels similar to annotations? All custom targets now have empty labels...

[andrewazores]

There are basically three kind of key-value stores attached to targets:

• labels
• annotations.platform
• annotations.cryostat

Labels are implicitly meant to come from the deployment platform, along with the platform annotations. ie. in a k8s environment with targets defined by the KubeApiPlatformClient, those two fields are copied from the k8s Endpoints/Pods objects etc.

Cryostat annotations are the ones that add extra information from the application, or in this case the client/user.

Now that there is the Discovery Plugin API it's possible for a client to register itself in a way that allows it to publish its own labels and platform annotations however it pleases too.

I think it makes sense for the labels and platform annotations to continue to be "immutable" (or at least defined by a plugin that probably keeps them stable), whereas the Cryostat annotations can change arbitrarily including by interactive user intervention.

[tthvo]

Ahh right that makes sense! thanks for explaining :D