---
title: OpenFaaS and Kubernetes
date: 2017-08-27 18:30:00
---

Recently there has been a lot of news about [OpenFaaS](https://github.com/alexellis/faas)
and I wanted to try it out. As the rest of my tests have been done on
Kubernetes, I looked more closely to the [FaaS-Netes](https://github.com/alexellis/faas-netes).

Everything here was done on a local minikube deployment and using my test
Docker registry deployed on a server in the local network.

## Deployment
The first deployment was really easy. Once minikube is operational, it's
only two commands to deploy everything needed :
`git clone https://github.com/alexellis/faas-netes`
and then `kubectl apply -f ./faas.yml,monitoring.yml,rbac.yml`.

You can check on the status of everything either through the Kubernetes
dashboard (using `minikube dashboard` if you don't know the IP) or using
the OpenFaaS dashboard (through the port *31112*).

The second part is to get the OpenFaaS-cli tools that allows easy function
deployment. As I'm not a huge fan of the `curl -sSL ... | sudo sh` install
method, I downloaded manually the executable from the [release page](https://github.com/alexellis/faas-cli/releases)
and added it the PATH.

## Use of a private Docker registry
Before this, I always deployed my stuff by hand of the Kubernetes cluster
and thus had no problems with the authentication using the *imagePullSecrets*
in the yaml deployment file. This time as OpenFaaS deploys containers as needed,
I had to configure the nodes to authenticate automatically. Fortunately,
it was this easy :

* Create the secret 

``` bash
$ kubectl create secret docker-registry myregistrykey \
    --docker-server=registry.local \
    --docker-username=user \
    --docker-password=pass \
    --docker-email none@registry.local
```

* Modify the service account to add `imagePullSecrets` to every image pull

``` bash
$ kubectl patch serviceaccount default \
    -p '{"imagePullSecrets": [{"name": "myregistrykey"}]}'
```

* It works.

## First test

I the followed the [Your first serverless Python function with OpenFaaS](https://blog.alexellis.io/first-faas-python-function/)
blog post by the creator of the system. First creating a new directory
for this function and adding the basic content needed for an Hello World

``` bash
$ mkdir -p ~/functions/hello-python
$ cd ~/functions
$ cat > hello-python/handler.py <<EOF
def handle(req):  
    print("Hello! You said: " + req)
EOF
$ cat > stack.yml <<EOF
provider:  
  name: faas
  gateway: http://192.168.42.99:31112

functions:  
  hello-python:
    lang: python
    handler: ./hello-python/
    image: registry.local/faas-hello-python:1.0
EOF
```

This makes the basic structure for a function. All in all, it's really
easy: One file contains the function that will be called, the other
contains the description of the deployment.

The to deploy our function, three commands will do everything needed


``` bash
$ faas-cli -action build -f ./stack.yml
$ faas-cli -action push -f ./stack.yml
$ faas-cli -action deploy -f ./stack.yml
```

And bam, everything is deployed and ready to recieve requests

```
curl http://192.168.42.99:31112/function/hello-python -d test
``` 

I think that I will play for a long time with this now ..