New to AppsCode Service Broker? Please start here.
This tutorial will show you how to use AppsCode Service Broker to provision and deprovision an Memcached cluster and bind to the Memcached service.
Before we start, you need to have a Kubernetes cluster, and the kubectl command-line tool must be configured to communicate with your cluster. If you do not already have a cluster, you can create one by using Minikube. Then install Service Catalog onto your cluster. If you haven’t, please see the installation instructions for Service Catalog. Optionally you may install the Service Catalog CLI, svcat. Examples for both svcat and kubectl are provided so that you may follow this walk-through using svcat or using only kubectl.
If you’ve AppsCode Service Broker installed, then we are ready for the next step. If not, follow the instructions to install KubeDB and AppsCode Service Broker.
To keep things isolated, we are going to use a separate namespace called demo throughout this tutorial.
$ kubectl create ns demo
namespace/demo created
All commands in this document assume that you’re operating out of the root of this repository.
First, list the available ClusterServiceClass resources:
$ kubectl get clusterserviceclasses
NAME EXTERNAL-NAME BROKER AGE
2010d83f-d908-4d9f-879c-ce8f5f527f2a postgresql appscode-service-broker 5m
315fc21c-829e-4aa1-8c16-f7921c33550d elasticsearch appscode-service-broker 5m
938a70c5-f2bc-4658-82dd-566bed7797e9 mysql appscode-service-broker 5m
ccfd1c81-e59f-4875-a39f-75ba55320ce0 redis appscode-service-broker 5m
d690058d-666c-45d8-ba98-fcb9fb47742e mongodb appscode-service-broker 5m
d88856cb-fe3f-4473-ba8b-641480da810f memcached appscode-service-broker 5m
$ svcat get classes
NAME NAMESPACE DESCRIPTION
+---------------+-----------+------------------------------+
postgresql KubeDB managed PostgreSQL
elasticsearch KubeDB managed ElasticSearch
mysql KubeDB managed MySQL
redis KubeDB managed Redis
mongodb KubeDB managed MongoDB
memcached KubeDB managed Memcached
Now, describe memcached class from the Service Broker.
$ svcat describe class memcached
Name: memcached
Scope: cluster
Description: KubeDB managed Memcached
Kubernetes Name: d88856cb-fe3f-4473-ba8b-641480da810f
Status: Active
Tags:
Broker: appscode-service-broker
Plans:
NAME DESCRIPTION
+----------------+--------------------------------+
demo-memcached Demo Memcached
memcached Memcached with custom
specification
To view the details of any plan in this class use command $ svcat describe plan <class_name>/<plan_name>. For example:
$ svcat describe plan memcached/memcached --scope cluster
Name: memcached
Description: Memcached with custom specification
Kubernetes Name: d40e49b2-f8fb-4d47-96d3-35089bd0942d
Status: Active
Free: true
Class: memcached
Instances:
No instances defined
Here we,ve used
--scopeflag to specify that ourClusterServiceBroker,ClusterServiceClassandClusterServiceBrokerresources are cluster scoped (not namespaced scope)
AppsCode Service Broker currently supports two plans for memcached class as we can see above. Using demo-memcached plan we can provision a demo Memcached database. And using memcached plan we can provision a custom Memcached database with the full functionality of a Memcached CRD.
AppsCode Service Broker accepts only metadata and Memcached Spec as parameters for the plans of memcached class. The metadata and spec should be provided with key "metadata" and "spec" respectively. The metadata is optional for both of the plans available. But the spec is required for the custom plan and it must be valid.
Since a ClusterServiceClass named memcached exists in the cluster with a ClusterServicePlan named memcached, we can create a ServiceInstance pointing to them with custom specification as parameters.
Unlike
ClusterServiceBroker,ClusterServiceClassandClusterServicePlanresources,ServiceInstanceresources must be namespaced. The latest version of .service catalog supportsServiceBroker,ServiceClassandServicePlanresources that are namespace scoped and alternative toClusterServiceBroker,ClusterServiceClassandClusterServicePlanresources.
Create the ServiceInstance:
$ kubectl create -f docs/examples/memcached-instance.yaml
serviceinstance.servicecatalog.k8s.io/memcached created
After it is created, the service catalog controller will communicate with the service broker server to initiate provisioning. Now, see the details:
$ svcat describe instance memcached --namespace demo
Name: memcached
Namespace: demo
Status: Ready - The instance was provisioned successfully @ 2018-12-26 05:38:02 +0000 UTC
Class: memcached
Plan: memcached
Parameters:
metadata:
labels:
app: my-memcached
spec:
podTemplate:
spec:
resources:
limits:
cpu: 500m
memory: 128Mi
requests:
cpu: 250m
memory: 64Mi
replicas: 3
terminationPolicy: WipeOut
version: 1.5.4-v1
Bindings:
No bindings defined
The yaml configuration of this ServiceInstance:
kubectl get serviceinstance memcached --namespace demo -o yaml
Output:
apiVersion: servicecatalog.k8s.io/v1beta1
kind: ServiceInstance
metadata:
creationTimestamp: "2018-12-26T05:38:01Z"
finalizers:
- kubernetes-incubator/service-catalog
generation: 1
labels:
app: appscode-service-broker
name: memcached
namespace: demo
resourceVersion: "101"
selfLink: /apis/servicecatalog.k8s.io/v1beta1/namespaces/demo/serviceinstances/memcached
uid: 6878eb72-08d0-11e9-9fa4-0242ac110006
spec:
clusterServiceClassExternalName: memcached
clusterServiceClassRef:
name: d88856cb-fe3f-4473-ba8b-641480da810f
clusterServicePlanExternalName: memcached
clusterServicePlanRef:
name: d40e49b2-f8fb-4d47-96d3-35089bd0942d
externalID: 6878eb3d-08d0-11e9-9fa4-0242ac110006
parameters:
metadata:
labels:
app: my-memcached
spec:
podTemplate:
spec:
resources:
limits:
cpu: 500m
memory: 128Mi
requests:
cpu: 250m
memory: 64Mi
replicas: 3
terminationPolicy: WipeOut
version: 1.5.4-v1
updateRequests: 0
userInfo:
groups:
- system:masters
- system:authenticated
uid: ""
username: minikube-user
status:
asyncOpInProgress: false
conditions:
- lastTransitionTime: "2018-12-26T05:38:02Z"
message: The instance was provisioned successfully
reason: ProvisionedSuccessfully
status: "True"
type: Ready
deprovisionStatus: Required
externalProperties:
clusterServicePlanExternalID: d40e49b2-f8fb-4d47-96d3-35089bd0942d
clusterServicePlanExternalName: memcached
parameterChecksum: 9627fe20432ac96997f9ff1983cb3cb6e3b1a2d14184f2e44761a0eb13c31993
parameters:
metadata:
labels:
app: my-memcached
spec:
podTemplate:
spec:
resources:
limits:
cpu: 500m
memory: 128Mi
requests:
cpu: 250m
memory: 64Mi
replicas: 3
terminationPolicy: WipeOut
version: 1.5.4-v1
userInfo:
groups:
- system:masters
- system:authenticated
uid: ""
username: minikube-user
observedGeneration: 1
orphanMitigationInProgress: false
provisionStatus: Provisioned
reconciledGeneration: 1
We have a ready ServiceInstance. To use this service, we can bind to it. AppsCode Service Broker currently supports no parameter for binding. Now, create a ServiceBinding resource:
$ kubectl create -f docs/examples/memcached-binding.yaml
servicebinding.servicecatalog.k8s.io/memcached created
Once the ServiceBinding resource is created, the service catalog controller initiates binding process by communicating with the service broker server. In general, the broker server returns the necessary credentials in this step. Then the service catalog controller will insert them into a Kubernetes Secret object.
$ kubectl get servicebindings memcached --namespace demo
NAME SERVICE-INSTANCE SECRET-NAME STATUS AGE
memcached memcached memcached Ready 1m
$ svcat get bindings memcached --namespace demo
NAME NAMESPACE INSTANCE STATUS
+-----------+-----------+-----------+--------+
memcached demo memcached Ready
$ svcat describe bindings memcached --namespace demo
Name: memcached
Namespace: demo
Status: Ready - Injected bind result @ 2018-12-26 07:58:54 +0000 UTC
Secret: memcached
Instance: memcached
Parameters:
No parameters defined
Secret Data:
Host 18 bytes
Password 4 bytes
Port 5 bytes
Protocol 0 bytes
RootCert 4 bytes
URI 26 bytes
Username 4 bytes
You can see the secret data by passing --show-secrets flag to the above command. The yaml configuration of this ServiceBinding resource is as follows:
kubectl get servicebindings memcached --namespace demo -o yaml
Output:
apiVersion: servicecatalog.k8s.io/v1beta1
kind: ServiceBinding
metadata:
creationTimestamp: "2018-12-26T07:58:53Z"
finalizers:
- kubernetes-incubator/service-catalog
generation: 1
labels:
app: appscode-service-broker
name: memcached
namespace: demo
resourceVersion: "132"
selfLink: /apis/servicecatalog.k8s.io/v1beta1/namespaces/demo/servicebindings/memcached
uid: 16bb8d67-08e4-11e9-9fa4-0242ac110006
spec:
externalID: 16bb8d1a-08e4-11e9-9fa4-0242ac110006
instanceRef:
name: memcached
secretName: memcached
userInfo:
groups:
- system:masters
- system:authenticated
uid: ""
username: minikube-user
status:
asyncOpInProgress: false
conditions:
- lastTransitionTime: "2018-12-26T07:58:54Z"
message: Injected bind result
reason: InjectedBindResult
status: "True"
type: Ready
externalProperties:
userInfo:
groups:
- system:masters
- system:authenticated
uid: ""
username: minikube-user
orphanMitigationInProgress: false
reconciledGeneration: 1
unbindStatus: Required
Here, the status has Ready condition which means the binding is now ready for use. This binding operation creates a Secret named memcached in namespace demo.
$ kubectl get secrets --namespace demo
NAME TYPE DATA AGE
default-token-2zx6l kubernetes.io/service-account-token 3 153m
memcached Opaque 7 5m57s
We can now delete the ServiceBinding resource we created in the Binding step (it is called Unbinding the ServiceInstance)
$ kubectl delete servicebinding memcached --namespace demo
servicebinding.servicecatalog.k8s.io "memcached" deleted
$ svcat unbind memcached --namespace demo
deleted memcached
After completion of unbinding, the Secret named memcached should be deleted.
$ kubectl get secrets --namespace demo
NAME TYPE DATA AGE
default-token-2zx6l kubernetes.io/service-account-token 3 174m
After unbinding the ServiceInstance, our next step is deleting the ServiceInstance resource we provisioned before. It is called Deprovisioning.
$ kubectl delete serviceinstance memcached --namespace demo
serviceinstance.servicecatalog.k8s.io "memcached" deleted
$ svcat deprovision memcached --namespace demo
deleted memcached
To cleanup the cluster, just uninstall the broker. It’ll delete the ClusterServiceBroker resource. Then service catalog controller automatically deletes all ClusterServiceClass and ClusterServicePlan resources that came from that broker.
$ kubectl get clusterserviceclasses
No resources found.
$ svcat get classes
NAME NAMESPACE DESCRIPTION
+------+-----------+-------------+