This commit includes several pieces of functionality to enable services
to be removed and the page to present information that this has happened
but also keep the deleted information on the page. Along with the more
usual blocking query based listing.
To enable this:
1. Implements `meta` on the model (only available on collections in
ember)
2. Adds new `catchable` ComputedProperty alongside a `listen` helper for
working with specific errors that can be thrown from EventSources in an
ember-like way. Briefly, normal computed properties update when a
property changes, EventSources can additionally throw errors so we can
catch them and show different visuals based on that.
More recommendations for blocking queries clients was added here:
https://github.com/hashicorp/consul/pull/5358
This commit mainly adds cursor/index validation/correction based on
these recommendations (plus tests)
The recommendations also suggest that clients should include rate
limiting. Because of this, we've moved the throttling out of Consul UI
specific code and into Blocking Query specific code. Currently the 'rate
limiting' in this commit only adds a sleep to every iteration of the
loop, which is not the recommended approach, but the code here organizes
the throttling functionality into something we can work with later to
provide something more apt.
- Maintain http headers as JSON-API meta for all API requests (#4946)
- Add EventSource ready for implementing blocking queries
- EventSource project implementation to enable blocking queries for service and node listings (#5267)
- Add setting to enable/disable blocking queries (#5352)
John Cowen