New article on OpenFaaS

articles/2017-08-27-openfaaskubernetes.md

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+---
+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 ..