OpenWhisk Deployment on Kubernetes
Apache OpenWhisk is an open source, distributed Serverless platform that executes functions (fx) in response to events at any scale. The OpenWhisk platform supports a programming model in which developers write functional logic (called Actions), in any supported programming language, that can be dynamically scheduled and run in response to associated events (via Triggers) from external sources (Feeds) or from HTTP requests.
This repository supports deploying OpenWhisk to Kubernetes. It contains a Helm chart that can be used to deploy the core OpenWhisk platform and optionally some of its Event Providers to both single-node and multi-node Kubernetes clusters.
Table of Contents
- Prerequisites: Kubernetes and Helm
- Deploying OpenWhisk
- Administering OpenWhisk
- Development and Testing
Prerequisites: Kubernetes and Helm
Kubernetes is a container orchestration platform that automates the deployment, scaling, and management of containerized applications. Helm is a package manager for Kubernetes that simplifies the management of Kubernetes applications. You do not need to have detailed knowledge of either Kubernetes or Helm to use this project, but you may find it useful to review their basic documentation to become familiar with their key concepts and terminology.
Your first step is to create a Kubernetes cluster that is capable of supporting an OpenWhisk deployment. Although there are some technical requirements that the Kubernetes cluster must satisfy, any of the options described below is acceptable.
Simple Docker-based options
The simplest way to get a small Kubernetes cluster suitable for development and testing is to use one of the Docker-in-Docker approaches for running Kubernetes directly on top of Docker on your development machine. Configuring Docker with 4GB of memory and 2 virtual CPUs is sufficient for the default settings of OpenWhisk. Depending on your host operating system, we recommend the following:
- MacOS: Use the built-in Kubernetes support in Docker for Mac version 18.06 or later. Please follow our setup instructions to initially create your cluster.
- Linux: Use kubeadm-dind-cluster, but carefully follow our setup instructions because the default setup of kubeadm-dind-cluster does not meet the requirements for running OpenWhisk.
- Windows: Use the built-in Kubernetes support in Docker for Windows version 18.06 or later. Please follow our setup instructions to initially create your cluster.
Minikube provides a Kubernetes cluster running inside a virtual machine (for example VirtualBox). It can be used on MacOS, Linux, or Windows to run OpenWhisk, but is somewhat less flexible than the docker-in-docker options described above. Configuring the Minikube VM with 4GB of memory and 2 virtual CPUs is sufficient for the default settings of OpenWhisk. For details on setting up Minikube, see these setup instructions.
Using a Kubernetes cluster from a cloud provider
You can also provision a Kubernetes cluster from a cloud provider, subject to the cluster meeting the technical requirements. You will need at least 1 worker node with 4GB of memory and 2 virtual CPUs to deploy the default configuration of OpenWhisk. You can deploy to significantly larger clusters by scaling up the replica count of the various components and labeling multiple nodes as invoker nodes. We have detailed documentation on using Kubernetes clusters from the following major cloud providers:
We would welcome contributions of documentation for Azure (AKS) and any other public cloud providers.
Helm is a tool to simplify the
deployment and management of applications on Kubernetes clusters. Helm
consists of the
helm command line tool that you install on your
development machine and the
tiller runtime that is deployed on your
For details on installing Helm, see these instructions.
In short if you already have the
helm cli installed on your development machine,
you will need to execute these two commands and wait a few seconds for the
tiller-deploy pod in the
kube-system namespace to be in the
helm init kubectl create clusterrolebinding tiller-cluster-admin --clusterrole=cluster-admin --serviceaccount=kube-system:default
Now that you have your Kubernetes cluster and have installed and initialized Helm, you are ready to deploy OpenWhisk.
You will use Helm to deploy OpenWhisk to your Kubernetes cluster. There are four deployment steps that are described in more detail below in the rest of this section.
- Initial cluster setup. You will label your Kubernetes worker nodes to indicate their intended usage by OpenWhisk.
- Customize the deployment. You will
mycluster.yamlthat specifies key facts about your Kubernetes cluster and the OpenWhisk configuration you wish to deploy.
- Deploy OpenWhisk with Helm. You will use Helm and
mycluster.yamlto deploy OpenWhisk to your Kubernetes cluster.
- Configure the
wskCLI. You need to tell the
wskCLI how to connect to your OpenWhisk deployment.
Indicate the Kubernetes worker nodes that should be used to execute
user containers by OpenWhisk's invokers. Do this by labeling each node with
openwhisk-role=invoker. In its default configuration,
OpenWhisk assumes it has exclusive use of these invoker nodes and
will schedule work on them directly, completely bypassing the Kubernetes
scheduler. For a single node cluster, simply do
kubectl label nodes --all openwhisk-role=invoker
If you have a multi-node cluster, then for each node <INVOKER_NODE_NAME> you want to be an invoker, execute
$ kubectl label nodes <INVOKER_NODE_NAME> openwhisk-role=invoker
For more precise control of the placement of the rest of OpenWhisk's
pods on a multi-node cluster, you can optionally label additional
non-invoker worker nodes. Use the label
to indicate nodes which should run the OpenWhisk control plane
(the controller, kafka, zookeeeper, and couchdb pods).
If you have dedicated Ingress nodes, label them with
openwhisk-role=edge. Finally, if you want to run the OpenWhisk
Event Providers on specific nodes, label those nodes with
Customize the Deployment
You must create a
mycluster.yaml file to record key aspects of your
Kubernetes cluster that are needed to configure the deployment of
OpenWhisk to your cluster. For details, see the documentation
appropriate to your Kubernetes cluster:
- Docker for Mac
- IBM Kubernetes Service (IKS)
- IBM Cloud Private (ICP)
- Google (GKE)
- Amazon (EKS)
Beyond the Kubernetes cluster specific configuration information,
mycluster.yaml file is also used
to customize your OpenWhisk deployment by enabling optional features
and controlling the replication factor of the various microservices
that make up the OpenWhisk implementation. See the configuration
choices documentation for a
discussion of the primary options.
Deploy With Helm
Deployment can be done by using the following single command:
helm install ./helm/openwhisk --namespace=openwhisk --name=owdev -f mycluster.yaml
For simplicity, in this README, we have used
owdev as the release name and
openwhisk as the namespace into which the Chart's resources will be deployed.
You can use different names, or not specify a release name at all and let
Helm auto-generate one for you.
You can use the command
helm status owdev to get a summary
of the various Kubernetes artifacts that make up your OpenWhisk
deployment. Once the
install-packages Pod is in the
your OpenWhisk deployment is ready to be used.
Configure the wsk CLI
Configure the OpenWhisk CLI, wsk, by setting the auth and apihost
properties (if you don't already have the wsk cli, follow the
to get it). Replace
with the actual values from your mycluster.yaml.
wsk property set --apihost <whisk.ingress.apiHostName>:<whisk.ingress.apiHostPort> wsk property set --auth 23bc46b1-71f6-4ed5-8c54-816aa4f8c502:123zO3xZCLrMN6v2BKK1dXYFpXlPkccOFqm12CdAsMgRU4VrNZ9lyGVCGuMDGIwP
Configuring the CLI for Kubernetes on Docker for Mac and Windows
docker0 network interface does not exist in the Docker for Mac/Windows
host environment. Instead, exposed NodePorts are forwarded from localhost
to the appropriate containers. This means that you will use
whisk.ingress.apiHostName when configuring
wsk cli and replace
with the actual values from your mycluster.yaml.
wsk property set --apihost localhost:<whisk.ingress.apiHostPort> wsk property set --auth 23bc46b1-71f6-4ed5-8c54-816aa4f8c502:123zO3xZCLrMN6v2BKK1dXYFpXlPkccOFqm12CdAsMgRU4VrNZ9lyGVCGuMDGIwP
Verify your OpenWhisk Deployment
Your OpenWhisk installation should now be usable. You can test it by following these instructions to define and invoke a sample OpenWhisk action in your favorite programming language.
You can also issue the command
helm test owdev to run the basic verification
test suite included in the OpenWhisk Helm chart.
Note: if you installed self-signed certificates, which is the default
for the OpenWhisk Helm chart, you will need to use
wsk -i to
suppress certificate checking. This works around
cannot validate certificate errors from the
If your deployment is not working, check our troubleshooting guide for ideas.
Wskadmin is the tool to perform various administrative operations against an OpenWhisk deployment.
Since wskadmin requires credentials for direct access to the database (that is not normally accessible to the outside), it is deployed in a pod inside Kubernetes that is configured with the proper parameters. You can run
kubectl. You need to use the
<namespace> and the deployment
<name> that you configured with
--name when deploying.
You can then invoke
kubectl -n <namespace> -ti exec <name>-wskadmin -- wskadmin <parameters>
For example, is your deployment name is
owdev and the namespace is
openwhisk you can list users in the
guest namespace with:
$ kubectl -n openwhisk -ti exec owdev-wskadmin -- wskadmin user list guest 23bc46b1-71f6-4ed5-8c54-816aa4f8c502:123zO3xZCLrMN6v2BKK1dXYFpXlPkccOFqm12CdAsMgRU4VrNZ9lyGVCGuMDGIwP
Check here for details about the available commands.
Development and Testing OpenWhisk on Kubernetes
This section outlines how common OpenWhisk development tasks are supported when OpenWhisk is deployed on Kubernetes using Helm.
Running OpenWhisk test cases
Some key differences in a Kubernetes-based deployment of OpenWhisk are
that deploying the system does not generate a
whisk.properties file and
that the various internal microservices (
etc.) are not directly accessible from the outside of the Kubernetes cluster.
Therefore, although you can run full system tests against a
Kubernetes-based deployment by giving some extra command line
arguments, any unit tests that assume direct access to one of the internal
microservices will fail. The system tests can be executed in a
batch-style as shown below, where WHISK_SERVER and WHISK_AUTH are
replaced by the values returned by
wsk property get --apihost and
wsk property get --auth respectively.
cd $OPENWHISK_HOME ./gradlew :tests:testSystemBasic -Dwhisk.auth=$WHISK_AUTH -Dwhisk.server=https://$WHISK_SERVER -Dopenwhisk.home=`pwd`
You can also launch the system tests as JUnit test from an IDE by adding the same system properties to the JVM command line used to launch the tests:
-Dwhisk.auth=$WHISK_AUTH -Dwhisk.server=https://$WHISK_SERVER -Dopenwhisk.home=`pwd`
Deploying a locally built docker image.
If you are using Kubernetes in Docker, it is
straightforward to deploy local images by adding a stanza to your
mycluster.yaml. For example, to use a locally built controller image,
just add the stanza below to your
mycluster.yaml to override the default
behavior of pulling a stable
openwhisk/controller image from Docker Hub.
controller: imageName: "whisk/controller" imageTag: "latest"
Selectively redeploying using a locally built docker image
You can use the
helm upgrade command to selectively redeploy one or
more OpenWhisk componenets. Continuing the example above, if you make
additional changes to the controller source code and want to just
redeploy it without redeploying the entire OpenWhisk system you can do
# Execute these commands in your openwhisk directory ./gradlew distDocker docker tag whisk/controller whisk/controller:v2
Then, edit your
mycluster.yaml to contain:
controller: imageName: "whisk/controller" imageTag: "v2"
Redeploy with Helm by executing this commaned in your openwhisk-deploy-kube directory:
helm upgrade ./helm/openwhisk --namespace=openwhisk --name=owdev -f mycluster.yaml
Use the following command to remove all the deployed OpenWhisk components:
helm delete owdev
Helm does keep a history of previous deployments. If you want to completely remove the deployment from helm, for example so you can reuse owdev to deploy OpenWhisk again, use the command:
helm delete owdev --purge
If your OpenWhisk deployment is not working, check our troubleshooting guide for ideas.
Report bugs, ask questions and request features here on GitHub.
You can also join our slack channel and chat with developers. To get access to our slack channel, request an invite here.
Apache OpenWhisk Deployment on Kubernetes is an effort undergoing incubation at The Apache Software Foundation (ASF), sponsored by the Apache Incubator. Incubation is required of all newly accepted projects until a further review indicates that the infrastructure, communications, and decision making process have stabilized in a manner consistent with other successful ASF projects. While incubation status is not necessarily a reflection of the completeness or stability of the code, it does indicate that the project has yet to be fully endorsed by the ASF.