Solution Arsenal

Solution Arsenal (SolAr) is an application catalog based on Open Component Model packages (ocm.software) and fleet rollout management for these solutions onto Kubernetes Clusters. It features a catalog of solutions, which are application bundles provided as OCM packages from an OCI compliant registry. Additionally Kubernetes clusters can be registered with SolAr to turn them into deployment targets for the solutions from the catalog. The deployment itself then uses OCM Controllers with fluxCD as a deployer (https://ocm.software/docs/concepts/ocm-controllers/).

Features and Requirements

Non-functional Technical Requirements

• SolAr has a backend written entirely in golang 1.25 or newer
• SolAr aims for a golang report card with A+ status
• SolAr aims for a test coverage of above 85% in general
• VERY IMPORTANT: The backend is implemented as an API Extension Server to Kubernetes. The starting point is the apiserver-kit provided here: https://github.com/opendefensecloud/apiserver-kit
• SolAr follows the Kubernetes Resource Model and thus is entirely configurable via Kubernetes Resources
• SolAr has an extensive web ui that exposes all features and functionalities in a consistent and user friendly manner
• SolArs web ui ensures that
• SolAr uses next.js for frontend and its apis and tailwind css for styling
• SolAr creates Docker OCI Images for every component according to best practices for low CVE and minimal secure images
• SolAr features a comprehensive Helm chart for deployment using helm 4.x

Components

SolAr itself has several components:

• solar-apiserver contains the catalog data and target cluster registrations and their desired state. The component is implemented as extension apiserver.
• solar-discovery continuously scans an OCI registry for relevant OCM packages, that are marked to be exposed to a catalog. It updates the solar-apiserver accordingly.
• solar-renderer is a component watching the solar-apiserver for desired state updates to render and update the relevant OCI images containing the deployment manifests.
• solar-ui is a management UI, which allows users to interact with solar-apiserver to explore the catalog and manage deployments.
• solar-agent runs in registered clusters to update the cluster status in solar-apiserver.

The backend is implemented as an API Extension Server to Kubernetes. The starting point is the kubernetes Sample API Server https://github.com/kubernetes/sample-apiserver

Roles and Permissions

• Users of SolAr can be organized in Groups in a single-layer flat hierarchy.
• Users in SolAr can have one or more of the following roles:
  • Solution Maintainer: Can create, update, delete solutions in the catalog by adding either specific OCM packages or a complete repository from a registry. Can further provide the permission to use the solution to other Groups
  • Cluster Maintainer: Can register and de-register Kubernetes Clusters with SolAr. Can assign and unassign clusters as deployment target to Groups.
  • Deployment Coordinator: Needs to be a member of a group that has solutions and clusters attached to it via permissions. Can then configure which solutions are to be deployed to which clusters and which are to be deleted
  • Super Admin: Has all permissions in the entire system. (dangerous!)

Features for Solutions

• Solution packages are checked to have the correct attestations regarding previous security scans or STIG conformance etc. before deployment to a target cluster
• Solutions can be transported from one SolAr instance to another by using the ARC project: https://github.com/opendefensecloud/solution-arsenal/

Features for Cluster Registration

• Technical registration with access credentials to the cluster
• Information about the clusters' available capacity in terms of cpu, memory, gpu, storage
• The security domain the cluster operates in. The list of available security domains feeds from a configurable list that can be configured on a system level of SolAr as an array of strings
• Further constraints for deployment to a cluster like required attestations for solutions can be configured on a per cluster or cluster group level

Features for Solution deployments

• Solution deployments follow the gitless GitOps pattern where the deployment definitions are provided to fluxCD as OCI images and are hosted in the same registry the catalog uses.
• An option to define the max number of users for the solution to determine scaling parameters
• A capacity pre-check to ensure the solution fits onto the target Cluster
• A capability pre-check to ensure all dependencies of the solution are met on the target cluster

"Use-Case Walkthrough"

Deployment

An OCM package is imported into an environment via ARC and stored in an OCI Registry.

The OCI registry is scanned by solar-discovery and a corresponding Component or ComponentVersion is created (via K8s API in solar-apiserver extension apiserver).

A user is onboarded and gets underlying permissions to manage Release, Profile and Target in a particular namespace (tenant separtion based on namespaces).

When the user interacts with the UI the same underlying permissions are used to manage the aforementioned K8s objects. The user creates a Target via the UI and retrieves a corresponding agent configuration. The agent configuration contains credentials that are required to access the solar-apiserver APIs relevant to the cluster within the tenant boundaries and access credentials for the source OCI registry including the desired state OCI image URL.

The user manually deploys the solar-agent to the target cluster with the retrieved agent configuration. The solar-agent does preflight checks and then creates fluxcd resources to reconcile the desired state from for this cluster using "Gitless GitOps" from the source OCI registry. The cluster status is updated and the user can now draft releases to deploy catalog items to the cluster.

The user creates a Release via the UI, the corresponding object causes the solar-renderer to update the desired state for this cluster in the OCI registry and a few moments later fluxcd instantiates the desired package. The solar-agent tracks the changes and reports the status changes back.

Catalog Chaining

The user is onboarded and registers a cluster.

The solar-agent is configured to allow syncs and an ARC endpoint as destination is specified. The solar-agent now also watches Sync-Resources in the catalog cluster. For each Sync resource an ARC Order is created/updated to trigger workflows pulling/scanning/pushing the packages to the destination.

The destination OCI is part of a second SolAr setup and the solar-discovery of the second SolAr setup picks up the packages and makes them available in the second environment.