faas/guide/deployment_k8s.md

Deployment guide for Kubernetes

Note: The best place to start is the README file in the faas or faas-netes repo.

This guide is for deployment to a vanilla Kubernetes 1.8 cluster running on Linux hosts.

Kubernetes

OpenFaaS is Kubernetes-native and uses Deployments, Services and Secrets. For more detail check out the "faas-netes" repository.

For deploying on a cloud that supports Kubernetes LoadBalancers you may also want to apply the configuration in: cloud/lb.yml.

1.0 Build a cluster

You can start evaluating FaaS and building functions on your laptop or on a VM (cloud or on-prem).

• 10 minute guides for minikube / kubeadm

2.0a Deploy with Helm

A Helm chart is provided faas-netes repo.

• OpenFaaS Helm chart

2.0b Deploy OpenFaaS

• Clone the code

$ git clone https://github.com/openfaas/faas-netes

• Deploy the services

$ cd faas-netes
$ kubectl apply -f ./faas.yml,monitoring.yml,rbac.yml

3.0

That's it. You now have OpenFaaS deployed.

For simplicity the default configuration uses NodePorts rather than an IngressController (which is more complicated to setup).

Service	TCP port
API Gateway / UI	31112
Prometheus	31119

If you're an advanced Kubernetes user, you can add an IngressController to your stack and remove the NodePort assignments.

• Deploy a sample function

There are currently no sample functions built into this stack, but we can deploy them quickly via the UI or FaaS-CLI.

Use the CLI

• Install the CLI

$ curl -sL cli.openfaas.com | sudo sh

Then clone some samples to deploy on your cluster.

$ git clone https://github.com/openfaas/faas-cli

Edit samples.yml and change your gateway URL from localhost:8080 to kubernetes-node-ip:31112.

i.e.

provider:  
  name: faas
  gateway: http://192.168.4.95:31112

Now deploy the samples:

$ faas-cli deploy -f samples.yml

The faas-cli also supports an override of --gateway http://... for example:

$ faas-cli deploy -f samples.yml --gateway http://127.0.0.1:31112

List the functions:

$ faas-cli list -f samples.yml

or

$ faas-cli list  --gateway http://127.0.0.1:31112
Function                      	Invocations    	Replicas
inception                     	0              	1    
nodejs-echo                   	0              	1    
ruby-echo                     	0              	1    
shrink-image                  	0              	1    
stronghash                    	2              	1

Invoke a function:

$ echo -n Test | faas-cli invoke stronghash --gateway http://127.0.0.1:31112
c6ee9e33cf5c6715a1d148fd73f7318884b41adcb916021e2bc0e800a5c5dd97f5142178f6ae88c8fdd98e1afb0ce4c8d2c54b5f37b30b7da1997bb33b0b8a31  -

• Learn about the CLI

Morning coffee with the OpenFaaS CLI

• Build your first Python function

Your first serverless Python function with OpenFaaS

Use the UI

The UI is exposed on NodePort 31112.

Click "New Function" and fill it out with the following:

Field	Value
Service	nodeinfo
Image	functions/nodeinfo:latest
fProcess	node main.js
Network	default

• Test the function

Your function will appear after a few seconds and you can click "Invoke"

You can also use the CLI like this:

$ echo -n "" | faas-cli invoke --gateway http://kubernetes-ip:31112 nodeinfo
$ echo -n "verbose" | faas-cli invoke --gateway http://kubernetes-ip:31112 nodeinfo

Asynchronous functions

Asynchronous invocation works by queuing requests with NATS Streaminig.

Deploy the asynchronous stack like this (or use the helm chart with the async override)

$ cd faas-netes
$ kubectl apply -f ./faas.async.yml,nats.yml,monitoring.yml,rbac.yml

• See also: Asynchronous function guide