k8s-class/kubeless

How to use Kubeless (Serverless) on Kubernetes

Install CLI

wget https://github.com/kubeless/kubeless/releases/download/v1.0.0-alpha.8/kubeless_linux-amd64.zip
unzip kubeless_linux-amd64.zip
sudo mv bundles/kubeless_linux-amd64/kubeless /usr/local/bin
rm -r bundles/

Deploy kubeless

kubectl create ns kubeless
kubectl create -f https://github.com/kubeless/kubeless/releases/download/v1.0.0-alpha.8/kubeless-v1.0.0-alpha.8.yaml 

Example function

python

kubeless function deploy hello --runtime python2.7 \
                               --from-file python-example/example.py \
                               --handler test.hello

NodeJS

kubeless function deploy myfunction --runtime nodejs6 \
                                --dependencies node-example/package.json \
                                --handler test.myfunction \
                                --from-file node-example/example.js

Commands

List Function

kubeless function ls

Expose function

* Only deploy the ingress controller if you do not have an ingress controller deployed. 
kubectl create -f nginx-ingress-controller-with-elb.yml

kubeless trigger http create myfunction --function-name myfunction --hostname myfunction.ghettolabs.io
kubeless trigger http create myfunction --function-name hello --hostname hello.ghettolabs.io

PubSub

Kafka Installation

export RELEASE=$(curl -s https://api.github.com/repos/kubeless/kafka-trigger/releases/latest | grep tag_name | cut -d '"' -f 4)
kubectl create -f https://github.com/kubeless/kafka-trigger/releases/download/$RELEASE/kafka-zookeeper-$RELEASE.yaml

Trigger and publish

kubeless trigger kafka create test --function-selector created-by=kubeless,function=hello --trigger-topic hello
kubeless topic publish --topic hello --data "this message will sent to output"

Call Function

kubeless function call myfunction --data 'This is some data'
kubeless function call hello --data 'This is some test data'

Create HTTP endpoint

kubeless trigger http create hello --function-name hello  --path echo --hostname hello.ghettolabs.io

curl --data '{"Another": "Echo"}' \
  --header "Host: hello.ghettolabs.io" \
  --header "Content-Type:application/json" \
  hello.ghettolabs.io/echo
  
  
  
  
  
  

Store token

Store your SLACK API TOKEN in a Kubernetes secret

kubectl create secret generic slack --from-literal=token=<your_token>

Launch the function

Edit bot.py to specify the proper channel.

make slack

Send a slack message

With a local proxy running:

kubeless function call slack --data '{"msg":"This is a message to SLACK"}'

Listen to Kubernetes events in SLACK

Launch the Kafka event sync:

kubeless topic create k8s
kubectl run events --image=skippbox/k8s-events:0.10.12

Deploy the function to get triggered on k8s events and send message to SLACK

make events