README
¶
Cluster Bundle
Note: This is not an officially supported Google product
The Cluster Bundle is a Kubernetes-related project developed by the Google Kubernetes team, that comes from Google's experience creating Kubernetes clusters in GKE and GKE On-Prem.
The Cluster Bundle is a Kubernetes type and has the goal of packaging all the necessary software that bootstraps and forms a functioning Kubernetes Cluster. It is currently highly experimental and will have likely have frequent, unannounced, breaking changes for a while until the API settles down.
The Cluster Bundle has three components:
- Type: A declarative, hermetic expression of the Cluster, and is designed for building automation related to managing Kubernetes clusters.
- Library: Go-library code for interacting with the Cluster Bundle
- CLI: A minimal CLI for interacting with Cluster Bundles.
Terminology
The Cluster Bundle tries to use familiar terminology wherever possible. That being said, the terms might be used in slightly or more precise was that you are used to:
- Object or Cluster Object: A Kubernetes configuration object. These are also sometimes referred to as manifests or yamls.
- Component: A versioned collection of Kubernetes objects.
- NodeConfig: A versioned set of configuration options for Kubernetes nodes.
- Bundle: A versioned collection of Kubernetes components and node configs.
Usage
Bundle CLI (bundlectl)
bundlectl is the name for the Bundle CLI and is the standard way for interacting
with Bundles. Install with go install github.com/GoogleCloudPlatform/k8s-cluster-bundle/cmd/bundlectl
Validation
Bundles have various constraints that must be validated. For functions in the Bundle library to work, the Bundle is generalled assumed to have already been validated. To validate a Bundle, run:
bundle validate <bundle>
Directory Structure
This directory should follow the structure the standard Go package layout specified in https://github.com/golang-standards/project-layout
pkg/: Library code.pkg/apis: APIs and schema for the Cluster Bundle.cmd/: Binaries. In particular, this contains thebundlerCLI which assists in modifying and inspecting Bundles.
Building and Testing
The Cluster Bundle relies on Bazel for building and testing.
Testing
To run the unit tests, run
bazel test ...
Or, it should work fine to use the go command
go test ./...
Regenerate BUILD files
To make using Bazel easier, we use Gazelle to automatically write Build targets. To automatically write the Build targets, run:
bazel run //:gazelle
Generating Proto Go Files
Currently, the schema for the Cluster Bundle is specified as Proto files. To generate the Go client libraries, first install protoc-gen-go and run:
pkg/apis/bundle/v1alpha1/regenerate-sources.sh
If new files are added, you may need to re-run Gazelle.
Directories
¶
| Path | Synopsis |
|---|---|
|
cmd
|
|
|
bundlectl
Command bundlectl is used for modifying bundles.
|
Command bundlectl is used for modifying bundles. |
|
pkg
|
|
|
apis
Package apis represents the directory for bundle APIs.
|
Package apis represents the directory for bundle APIs. |
|
apis/bundle
Package bundle is the internal version of the API.
|
Package bundle is the internal version of the API. |
|
apis/bundle/v1alpha1
Package v1alpha1 represents the v1alpha1 version of the Cluster Bundle API.
|
Package v1alpha1 represents the v1alpha1 version of the Cluster Bundle API. |
|
commands
Package commands contains commands used in the bundler command
|
Package commands contains commands used in the bundler command |
|
commands/cmdlib
Package cmdlib contains shared functions for the bundle CLI commands.
|
Package cmdlib contains shared functions for the bundle CLI commands. |
|
commands/filter
Package filter contains commands for filtering components and objects.
|
Package filter contains commands for filtering components and objects. |
|
converter
Package converter provides utilities for converting between various types.
|
Package converter provides utilities for converting between various types. |
|
core
Package core represents types and helpers that are used throughout the bundle.
|
Package core represents types and helpers that are used throughout the bundle. |
|
files
Package files contains methods and data types for manipulating files.
|
Package files contains methods and data types for manipulating files. |
|
filter
Package filter contains methods for filtering bundles.
|
Package filter contains methods for filtering bundles. |
|
find
Package find provides methods for searching through Bundles the contained components and configuration.
|
Package find provides methods for searching through Bundles the contained components and configuration. |
|
scheme
Package scheme containts library functions for creating/managing Kubernetes schemes.
|
Package scheme containts library functions for creating/managing Kubernetes schemes. |
|
testutil
Package testutil provides utilities for reading testdata from children directories.
|
Package testutil provides utilities for reading testdata from children directories. |
|
transformer
Package transformer provides transformations for bundles
|
Package transformer provides transformations for bundles |
|
validation
Package validation provides validation for Bundles
|
Package validation provides validation for Bundles |