runtime

README

pkg/runtime

This package contains a set of concrete structs and helper functions that provide a common controller implementation for an AWS service.

The top-level container struct in the package is ServiceController. A single instance of ServiceController is created (using NewServiceController()) from the cmd/controller/main.go file that contains the ACK controller entrypoint for a specific AWS service API.

ServiceController primarily serves as a way to glue the upstream sigs.k8s.io/controller-runtime (here on called ctrlrt for short since that alias we use in the ACK codebase to refer to that upstream repository) machinery together with ACK types that handle communication with the AWS service API.

The main ctrlrt types that ServiceController glues together are the ctrlrt.Manager and ctrlrt.Reconciler types. The ctrlrt.Manager type is used to bind a bunch of sigs.k8s.io/client-go and sigs.k8s.io/apimachinery infrastructure together into a common network server/listener structure. The ctrlrt.Reconciler type is an interface that provides a single Reconcile() method whose job is to reconcile the state of a single custom resource (CR) object.

The ServiceController.BindControllerManager() method accepts a ctrlrt.Manager object and is responsible for creating a reconciler for each kind of CR that the service controller will handle.

But how does the ServiceController know what kinds of CRs that it will handle?

There is a ServiceController.WithResourceManagerFactories() method that sets the ServiceController's collection of objects that implement the types.AWSResourceManagerFactory interface.

These resource manager factories produce objects that implement the types.AWSResourceManager interface, which is basic CRUD+L operations for a particular AWS resource against the backend AWS service API. The types.AWSResourceManagerFactory.For() method returns a types.AWSResourceManager object that has been created to handle a specific AWS service API resources for one AWS account. In this way, the single service controller can manage resources across multiple AWS accounts.

Resource manager factories are registered with a Registry object that is package-scoped to the individual service controller's services/{service}/pkg/resource package. See the example service's pkg/resource/registry.go file for how this package-scoped registry works. Individual resource manager factories are registered with this package-scoped Registry object using an init() call within a file named {resource}_manager_factory.go. For example, the Book resource in the example service's pkg/resource package has its resource manager factory registered in the init() function in the pkg/resource/book_resource_manager_factory.go file.

Documentation

Index

• func GetDefaultTags(config *ackconfig.Config, metadata *acktypes.RuntimeMetaObject) map[string]string
• func IsAdopted(res acktypes.AWSResource) bool
• func IsSynced(res acktypes.AWSResource) bool
• func NewAdoptionReconciler(sc acktypes.ServiceController, log logr.Logger, cfg ackcfg.Config, ...) acktypes.Reconciler
• func NewReconciler(sc acktypes.ServiceController, rmf acktypes.AWSResourceManagerFactory, ...) acktypes.AWSResourceReconciler
• func NewServiceController(svcAlias string, svcAPIGroup string, versionInfo VersionInfo) acktypes.ServiceController
• type Registry
  • func NewRegistry() *Registry
  • func (r *Registry) GetResourceManagerFactories() []types.AWSResourceManagerFactory
  • func (r *Registry) RegisterResourceManagerFactory(f types.AWSResourceManagerFactory)
• type VersionInfo

Functions

func GetDefaultTags

func GetDefaultTags(
	config *ackconfig.Config,
	metadata *acktypes.RuntimeMetaObject,
) map[string]string

GetDefaultTags provides Default tags (key value pairs) for given resource

func IsAdopted

func IsAdopted(res acktypes.AWSResource) bool

IsAdopted returns true if the supplied AWSResource was created with a non-nil ARN annotation, which indicates that the Kubernetes user who created the CR for the resource expects the ACK service controller to "adopt" a pre-existing resource and bring it under ACK management.

func IsSynced

func IsSynced(res acktypes.AWSResource) bool

IsSynced returns true if the supplied AWSResource's CR and associated backend AWS service API resource are in sync.

func NewAdoptionReconciler

func NewAdoptionReconciler(
	sc acktypes.ServiceController,
	log logr.Logger,
	cfg ackcfg.Config,
	metrics *ackmetrics.Metrics,
) acktypes.Reconciler

NewAdoptionReconciler returns a new adoptionReconciler object

func NewReconciler

func NewReconciler(
	sc acktypes.ServiceController,
	rmf acktypes.AWSResourceManagerFactory,
	log logr.Logger,
	cfg ackcfg.Config,
	metrics *ackmetrics.Metrics,
) acktypes.AWSResourceReconciler

NewReconciler returns a new reconciler object that

func NewServiceController

func NewServiceController(
	svcAlias string,
	svcAPIGroup string,
	versionInfo VersionInfo,
) acktypes.ServiceController

NewServiceController returns a new serviceController instance

Types

type Registry

type Registry struct {
	sync.RWMutex
	// contains filtered or unexported fields
}

func NewRegistry

func NewRegistry() *Registry

NewRegistry returns a thread-safe Registry object

func (*Registry) GetResourceManagerFactories

func (r *Registry) GetResourceManagerFactories() []types.AWSResourceManagerFactory

GetResourceManagerFactories returns AWSResourceManagerFactories that are registered with the RegistryA

func (*Registry) RegisterResourceManagerFactory

func (r *Registry) RegisterResourceManagerFactory(f types.AWSResourceManagerFactory)

RegisterResourceManagerFactory registers a resource manager factory with the package's registry

type VersionInfo

type VersionInfo struct {
	// GitCommit is the SHA1 commit for the service controller's code
	GitCommit string
	// GitVersion is the latest Git tag from the service controller's code
	GitVersion string
	// BuildDate is a timestamp of when the code was built
	BuildDate string
}

VersionInfo contains information about the version of the runtime and service controller in use