Clone this repository with --recursive to get the submodule example folder:
git clone --recursive https://github.com/endocode/ausroller
If your Kubernetes API server uses a self-signed certificate, you have to configure your kubectl properly.
Either set the certificate authority:
kubectl config set-cluster <NAME> --certificate-authority=/path/to/ca.crt
or just skip crtificate verification:
kubectl config set-cluster <NAME> --insecure-skip-tls-verify=true
Ausroller is a tool to create, update and rollout Kubernetes resource yamls from a template.
Our central configuration repository k8s-resources contains the
directories templates, rollout, namespaces and secrets.
.
├── namespaces
│ └── another-namespace.yaml
├── rollout
│ ├── default
│ │ ├── configmaps
│ │ ├── deployments
│ │ ├── pods
│ │ ├── replicationcontrollers
│ │ ├── secrets
│ │ └── services
│ ├── kube-system
│ │ ├── deployments
│ │ ├── replicationcontrollers
│ │ ├── secrets
│ │ └── services
│ └── another-namespace
│ ├── configmaps
│ ├── deployments
│ ├── pods
│ ├── replicationcontrollers
│ ├── secrets
│ └── services
├── secrets
│ ├── default
│ │ └── secret_vars.json
│ ├── kube-system
│ │ └── secret_vars.json
│ └── another-namespace
│ └── secret_vars.json
└── templates
├── configmaps
├── deployments
├── pods
├── replicationcontrollers
├── secrets
└── services
templates contains the deployment templates (Do'h!) and rollout contains the
latest Kubernetes resource yamls which are already rolled out in a specific
namespace. Additional namespaces have to be deployed once and are in the
namespace directory. This is the place where we store the productive
version numbers of all our components.
At the moment ausroller is not compatible with Python3. If you are using a distribution that defaults to Python3 e.g. Arch Linux you should use a virtual environment as follows:
virtualenv -p python2 ausroller
source ausroller/bin/activate
pip install git+https://github.com/endocode/ausroller@0.3.1
Remove the version number to install the latest version from the master branch.
Ausroller needs a configuration file to read the path to the "rollout" git repository from.
It looks for $HOME/.ausroller.ini by default but the path to the ausroller.ini
can be overwritten on command line: ausroller [...] -c /etc/ausroller.ini
Basic ausroller.ini looks like that:
[ausroller]
<kubectlpath = /opt/k8s/bin/kubectl>
[another-context]
repopath = /home/<user>/git/k8s-resources
If you omit the kubectlpath option ausroller will try to find kubectl on your $PATH to rollout your resources.
You must specify the path to the repository to use for each Kubernetes context you want to use.
List configured Kubernetes contexts:
kubectl config get-contexts
If everything is prepared you can run the ausroller with the four mandatory parameters:
ausroller --namespace another-namespace --context another-context --app your-app --ver 47.11-1a
This command looks up for Kubernetes resource template files e.g. called
your-app-deployment.tpl.yaml or your-app-configmap.tpl.yaml in the
directory templates/another-namespace/deployments/ resp.
templates/another-namespace/configmaps/ in your configured repo-path. It
will fill in the version given by the command line parameter --ver,
add and commit the created Kubernetes resource files in the path
rollout/another-namespace/deployments/your-app-deployment.yaml resp.
rollout/another-namespace/configmaps/your-app-configmap.yaml. Then it
checks if the Kubernetes resources already exist and updates it by running and
roll out the saved file by running kubectl apply -f your-app-configmap.yaml resp. kubectl apply -f your-app-deplyoment.yaml. If a Kubernetes resource is unknown ausroller
creates it.
If you want more explanatory commit messages in the repository you can run ausroller with the optional parameter --message :
ausroller --namespace another-namespace --context another-context --app my-app --ver 1.2.3-12a --message "Hotfix for foobar"
Create a normal deployment.yaml for your application but put the placeholder {{ app_version }} into the image: line instead of the Docker image tag. The placeholder will be substituted by the value of the --ver cli parameter when running ausroller.
Save and commit the template into the directory templates/deployments/ with the
filename <your-app>-deployment.tpl.yaml
Now run ausroller like that
ausroller --namespace another-namespace --context another-context --app your-app --ver 47.11-1a --message "First rollout"
Ausroller will take the template you create (choosen by the value of parameter --app), replace the {{ app_version}} placeholder by the value of the parameter --ver, add and commit the resulting file your-app-deplyoment.yaml to the directory rollout/another-namespace/deployments/ and create the deployment in the Kubernetes cluster.
In the following example we use ausroller to rollout Nginx in a certain
version. This will create a deployment and a service from our templates in the
example-resources/ folder. It also will produce a commit in that repository
with the according resource yamls.
After that we will upgrade the Nginx to a newer version.
kubectlhas to be configured to a cluster
For a quick-start use minikube to setup a local cluster.
For example bring up a cluster in a kvm virtual machine:
minikube --vm-driver=kvm start
Make sure that we have the namespace we want to rollout to:
kubectl apply -f example-resources/namespaces/another-namespace.yaml
Rollout Nginx. This will produce a commit in example-resources/:
ausroller --config example-resources/ausroller.ini --namespace another-namespace --context minikube --app nginx --ver 1.10.2-alpine
Check what happened:
kubectl --namespace=another-namespace get svc,deployment,pods
Upgrade Nginx:
ausroller --config example-resources/ausroller.ini --namespace another-namespace --context minikube --app nginx --ver 1.11.5-alpine
Again check what happened:
kubectl --namespace=another-namespace get svc,deployment,pods
Delete Kubernetes resources:
kubectl --namespace=another-namespace delete svc nginx-service
kubectl --namespace=another-namespace delete deployment nginx-deployment
kubectl delete namespace another-namespace
Remove the commits produced by ausroller:
( cd example-resources/ && git reset --hard HEAD~2 )
When implementing new features place some unit tests in the tests directory.
Running the unit tests:
python -m unittest discover -v tests