plugin/kubernetes: Watch EndpointSlices (#4209)

* initial commit

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* convert endpointslices to object.endpoints

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* add opt hard coded for now

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* check that server supports endpointslice

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* fix import grouping

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* dont use endpoint slice in 1.17 or 1.18

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* bump kind/k8s in circle ci to latest

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* drop k8s to latest supported by kind

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* use endpointslice name as endoint Name; index by Service name

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* use index key comparison in nsAddrs()

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* add Index to object.Endpoint fixtures; fix direct endpoint name compares

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* add slice dup check and test

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* todo

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* add ep-slice skew dup test for reverse

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* nsaddrs: de-dup ep-slice skew dups; add test

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* remove todo

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* address various feedback

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* consolidate endpoint/slice informer code

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* fix endpoint informer consolidation; use clearer func name

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* log info; use major/minor fields

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* fix nsAddr and unit test

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* add latency tracking for endpointslices

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* endpointslice latency unit test & fix

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* code shuffling

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* rename endpointslices in tests

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* remove de-dup from nsAddrs and test

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

* remove de-dup from findServices / test

Signed-off-by: Chris O'Haver <cohaver@infoblox.com>

.circleci/config.yml

@@ -21,8 +21,8 @@ integrationDefaults: &integrationDefaults
     image: ubuntu-1604:201903-01
   working_directory: ~/go/src/${CIRCLE_PROJECT_USERNAME}/coredns
   environment:
-    - K8S_VERSION: v1.18.2
-    - KIND_VERSION: v0.8.1
+    - K8S_VERSION: v1.19.1
+    - KIND_VERSION: v0.9.0
     - KUBECONFIG: /home/circleci/.kube/kind-config-kind
 
 setupKubernetes: &setupKubernetes