Funded by the EU.

faas-controller

The controller grants the appropriate RBAC roles to the FaaS-Operator component each time the operator creates a new namespace.

Description

The FaaS-Operator component is responsible for creating the necessary resources to run jobs. First of all, the operator creates a new namespace where all the resources will be deployed on. The operator must have total control of the newly created namespace and its resources. Furthermore, the namespace itself along with all its resources must be deleted, when all the jobs complete. Consequently, the operator should be granted the appropriate access roles. The controller identifies the namespaces created by the operator using the combination of the namespace name and a speciffic label added by the operator. Then, Kubernetes Roles and RoleBindings are created and deployed on the cluster. The RoleBinding Kubernetes resource links the Role resource with the operator's service account. The rationale behind this design decision follows.

The Kubernetes RBAC API declares four kinds of Kubernetes objects: Role, ClusterRole, RoleBinding and ClusterRoleBinding. The operator needs to just be able to create namespaces in the cluster, but must have admin access (create resources, delete namespace, etc.) only for the namespaces it created itself. This is an important security aspect. Even if the operator got compromised, the attack surface would be very small. The worst that could happen are the deletion of all namespaces created by the operator or the creation of a large number of new namespaces on the cluster. In either case, an attacker would not able to modify, delete or create other resources in the cluster.

Getting Started

Prerequisites

• go version v1.24.0+
• docker version 17.03+.
• kubectl version v1.11.3+.
• Access to a Kubernetes v1.11.3+ cluster.

To Deploy on the cluster

Build and push your image to the location specified by IMG:

make docker-build docker-push IMG=<some-registry>/faas-controller:tag

NOTE: This image ought to be published in the personal registry you specified. And it is required to have access to pull the image from the working environment. Make sure you have the proper permission to the registry if the above commands don’t work.

Install the CRDs into the cluster:

make install

Deploy the Manager to the cluster with the image specified by IMG:

make deploy IMG=<some-registry>/faas-controller:tag

NOTE: If you encounter RBAC errors, you may need to grant yourself cluster-admin privileges or be logged in as admin.

Create instances of your solution You can apply the samples (examples) from the config/sample:

kubectl apply -k config/samples/

NOTE: Ensure that the samples has default values to test it out.

To Uninstall

Delete the instances (CRs) from the cluster:

kubectl delete -k config/samples/

Delete the APIs(CRDs) from the cluster:

make uninstall

UnDeploy the controller from the cluster:

make undeploy

Project Distribution

Following the options to release and provide this solution to the users.

By providing a bundle with all YAML files

1. Build the installer for the image built and published in the registry:

make build-installer IMG=<some-registry>/faas-controller:tag

NOTE: The makefile target mentioned above generates an 'install.yaml' file in the dist directory. This file contains all the resources built with Kustomize, which are necessary to install this project without its dependencies.

2. Using the installer

Users can just run 'kubectl apply -f ' to install the project, i.e.:

kubectl apply -f https://raw.githubusercontent.com/<org>/faas-controller/<tag or branch>/dist/install.yaml

By providing a Helm Chart

1. Build the chart using the optional helm plugin

kubebuilder edit --plugins=helm/v1-alpha

2. See that a chart was generated under 'dist/chart', and users can obtain this solution from there.

NOTE: If you change the project, you need to update the Helm Chart using the same command above to sync the latest changes. Furthermore, if you create webhooks, you need to use the above command with the '--force' flag and manually ensure that any custom configuration previously added to 'dist/chart/values.yaml' or 'dist/chart/manager/manager.yaml' is manually re-applied afterwards.

NOTE: Run make help for more information on all potential make targets

More information can be found via the Kubebuilder Documentation

License

Copyright 2025.

Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except in compliance with the License. You may obtain a copy of the License at

http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software distributed under the License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the License for the specific language governing permissions and limitations under the License.