couchdb operator

this k8s operator allows you to run a 2.1 couchdb cluster on top of k8s.

status

• operator
  • RBAC support
  • CRD (CouchDB)
    • definition
    • management custom object add (spawn cluster)
    • management custom object update (update cluster)
    • management custom object delete (delete cluster)
  • deployment template (port, readyness, livelyness)
  • cluster management
    • credentials from configMap, secrets
    • pod anti affinity
    • node selection via labels
    • custom labels
    • new pod -> join cluster
    • old pod gone -> leave cluster
  • operator definition
• README

guiding notes

see 7 principles taken from coreOS post: https://coreos.com/blog/introducing-operators.html and https://github.com/kubernetes/community/blob/master/contributors/devel/controllers.md

prerequisites

• k8s >= 1.7.0

usage

$ kubectl apply -f k8s/resource-type.yml
$ kubectl apply -f k8s/deployment.yml

now, you can deploy a couchdb cluster like this:

apiVersion: "stable.couchdb.org/v1"
kind: CouchDB
metadata:
  name: my-couchdb-cluster
spec:
  version: "2.1.0"
  image:   "nicolai86/couchdb"
  replicas: 3 

the operator takes care of spawning the necessary pods and joining them into a single cluster.

development

required: golang 1.9+, kubernetes cluster (minikube, GKE, Azure...). To get a working operator locally, assuming kubectl is setup correctly:

$ go get -u github.com/golang/dep/cmd/dep
$ go get -du github.com/nicolai86/couchdb-operator
$ cd $(go env GOPATH)/src/github.com/nicolai86/couchdb-operator
$ dep ensure
$ OPERATOR_NAMESPACE=couchdb-operator 
$ OPERATOR_NAME=couchdb-operator 
$ KUBECONFIG=~/.kube/config 
$ go run main.go