[Feature] Blocking queries for /v1/catalog/datacenters

[ashald]

Is it possible to add blocking queries support to the /v1/catalog/datacenters endpoint? It'd help a lot for software that uses Consul to get some data (KV/services) across datacenter boundaries (such a Linkerd/Namerd). Instead of re-trying on HTTP 500 and storming Consul with requests it'd be possible to "patiently wait" until connectivity to the datacenter will recover.

[slackpad]

Hi @ashald I think we may be able to get this in for 0.8 or shortly after as we are doing some work in this area.

[ashald]

Great to hear! Thanks!

[fox-hellraiser]

@slackpad hi, any news for this feature?

[fox-hellraiser]

Issue is still open, but in 1.0.7 changelog I found this:

agent: Blocking queries on service-specific health and catalog endpoints now return a per-service X-Consul-Index improving watch performance on very busy clusters. [GH-3890]. Note this may break blocking clients that relied on undocumented implementation details as noted in the upgrade docs.

@slackpad can you clarify?