> For the complete documentation index, see [llms.txt](https://kubernetes.feisky.xyz/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://kubernetes.feisky.xyz/en/extension/api/aggregation.md). # Aggregation API Aggregation enables the amplification of Kubernetes API without altering its core code. What this means is that third-party services can be registered into Kubernetes API, which consequently allows for the access of these external services right within Kubernetes API. > Note: Another method for expanding the horizons of Kubernetes API is via [CustomResourceDefinition (CRD)](/en/extension/api/aggregation.md). ## Picking the Right Times for Aggregation | Conditions suited for API Aggregation | Perfect conditions to utilize independent API | | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------- | | If your API is [Declarative](https://kubernetes.io/docs/concepts/extend-kubernetes/api-extension/custom-resources/#declarative-apis). | If your API doesn't quite cut the [Declarative](https://kubernetes.io/docs/concepts/extend-kubernetes/api-extension/custom-resources/#declarative-apis) model. | | If you'd want your new types to be read and altered with `kubectl`. | `kubectl` support: Check `Not required` box | | Want to view your brand new types in a Kubernetes UI like the dashboard along with other built-in types? | Spare the thought if Kubernetes UI support isn't required. | | If you're building a new API from scratch. | If you're already equipped with a functioning program serving your API efficiently. | | If you are open to embracing the format restriction imposed on REST resource paths by Kubernetes, such as API Groups and Namespaces. (Dive deeper into the [API Overview](https://kubernetes.io/docs/concepts/overview/kubernetes-api/).) | If you need specific REST paths to gel with an existing REST API. | | If your resources seamlessly fit into a cluster or namespaces of a cluster. | If cluster or namespace scoped resources are bad fits; instead, you require control over resource path specifics. | | If you wish to tap into [Kubernetes API support features](https://kubernetes.io/docs/concepts/extend-kubernetes/api-extension/custom-resources/#common-features). | If those features aren't on your required list. | ## Jumpstarting API Aggregation Augment kube-apiserver by tweaking the configuration: ```bash --requestheader-client-ca-file= --requestheader-allowed-names=aggregator --requestheader-extra-headers-prefix=X-Remote-Extra- --requestheader-group-headers=X-Remote-Group --requestheader-username-headers=X-Remote-User --proxy-client-cert-file= --proxy-client-key-file= ``` If `kube-proxy` is a no-show on the Master, then this configuration is mandatory: ```bash --enable-aggregator-routing=true ``` ## Building the Extended API 1. Ensure the APIService API is on-board (usually, it is! Verify with `kubectl get apiservice` command) 2. Set up RBAC rules 3. Create a namespace to host your extended API service 4. Generate CA and certificates, vital for https 5. Create a 'secret' safehouse for storing certificates 6. Launch a deployment to serve your extended API service and configure the certificates using the previously generated 'secret', enabling https services 7. Create a ClusterRole and ClusterRoleBinding 8. Create a non-namespace apiservice; remember to set `spec.caBundle` 9. Rollout `kubectl get `; if everything's ticking right, it should return `No resources found.` Use the [apiserver-builder](https://github.com/kubernetes-incubator/apiserver-builder) tool for a smooth run through the above steps. ```bash # Initiate project $ cd GOPATH/src/github.com/my-org/my-project $ apiserver-boot init repo --domain $ apiserver-boot init glide # Create resources $ apiserver-boot create group version resource --group --version --kind # Compile $ apiserver-boot build executables $ apiserver-boot build docs # Run locally $ apiserver-boot run local # Run clustered $ apiserver-boot run in-cluster --name nameofservicetorun --namespace default --image gcr.io/myrepo/myimage:mytag $ kubectl create -f sample/.yaml ``` ## Examples To Check Out Visit [sample-apiserver](https://github.com/kubernetes/sample-apiserver) and [apiserver-builder/example](https://github.com/kubernetes-incubator/apiserver-builder/tree/master/example). --- # Agent Instructions This documentation is published with GitBook. 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