feat: Watch configMap for deletion

[helayoty]

• Set the patrol interval to ticker
• Check for configMap deletion event

[Fei-Guo]

Will returning true cause always retry?

[helayoty]

Yes. No specific error. We want to retry for all errors.

[helayoty]

manual e2e run:

helm install carbon-e2e --set apiServer.image.repository=helayoty/server --set carbonDataExporter.image.repository=helayoty/exporter --set carbonDataExporter.patrolInterval=15s --set apiServer.username=XXXXXX--set apiServer.password=YYYYY ./charts/carbon-intensity-exporter
NAME: carbon-e2e
LAST DEPLOYED: Wed Apr  5 07:13:45 2023
NAMESPACE: default
STATUS: deployed
REVISION: 1
TEST SUITE: None
+ kubectl wait --for=condition=available deploy carbon-e2e-carbon-intensity-exporter -n kube-system --timeout=300s
deployment.apps/carbon-e2e-carbon-intensity-exporter condition met
+ sleep 15
+ kubectl get configmap carbon-intensity -n kube-system
NAME               DATA   AGE
carbon-intensity   7      10s
+ kubectl describe configmap carbon-intensity -n kube-system
Name:         carbon-intensity
Namespace:    kube-system
Labels:       <none>
Annotations:  <none>

Data
====
message:
----

minForecast:
----
523.855390
numOfRecords:
----
288
forecastDateTime:
----
2023-04-05 14:15:00 +0000 UTC
lastHeartbeatTime:
----
2023-04-05 14:13:56.986976296 +0000 UTC m=+5.962670016
maxForecast:
----
578.662105

BinaryData
====
data: 29053 bytes

Events:  <none>
+ sleep 10
+ kubectl delete configmap carbon-intensity -n kube-system
configmap "carbon-intensity" deleted
+ sleep 15
+ kubectl get configmap carbon-intensity -n kube-system
NAME               DATA   AGE
carbon-intensity   7      4s
+ kubectl describe configmap carbon-intensity -n kube-system
Name:         carbon-intensity
Namespace:    kube-system
Labels:       <none>
Annotations:  <none>

Data
====
forecastDateTime:
----
2023-04-05 14:15:00 +0000 UTC
lastHeartbeatTime:
----
2023-04-05 14:14:27.126788961 +0000 UTC m=+36.103318068
maxForecast:
----
578.662105
message:
----

minForecast:
----
523.855390
numOfRecords:
----
288

BinaryData
====
data: 29053 bytes

Events:  <none>
+ sleep 5
+++ kubectl get pods -n kube-system -o=name
+++ grep carbon-e2e-carbon-intensity-exporter
+++ sed 's/^.\{4\}//'
++ echo carbon-e2e-carbon-intensity-exporter-778578866d-fgc7v
+ kubectl logs carbon-e2e-carbon-intensity-exporter-778578866d-fgc7v -c carbon-data-exporter -n kube-system
I0405 14:13:56.063652       1 options.go:108] Neither kubeconfig file nor control plane URL was specified. Falling back to in-cluster config.
I0405 14:13:56.064113       1 server.go:86] Inside server-> Run
I0405 14:13:56.064177       1 server.go:136] Inside server-> startExporter
I0405 14:13:56.064215       1 exporter.go:46] Inside exporter-> Run
I0405 14:13:56.064223       1 exporter.go:109] Inside exporter-> RefreshData
I0405 14:13:56.994834       1 configmap.go:69] configMap carbon-intensity has been created
I0405 14:14:11.997969       1 exporter.go:109] Inside exporter-> RefreshData
I0405 14:14:12.008032       1 configmap.go:103] configMap carbon-intensity has been deleted
I0405 14:14:12.147938       1 configmap.go:69] configMap carbon-intensity has been created
I0405 14:14:16.504308       1 exporter.go:109] Inside exporter-> RefreshData
I0405 14:14:16.658325       1 configmap.go:69] configMap carbon-intensity has been created
I0405 14:14:26.997542       1 exporter.go:109] Inside exporter-> RefreshData
I0405 14:14:27.008191       1 configmap.go:103] configMap carbon-intensity has been deleted
I0405 14:14:27.136142       1 configmap.go:69] configMap carbon-intensity has been created