kuberesolver

README

kuberesolver

Grpc Client-Side Load Balancer with Kubernetes name resolver

// Register kuberesolver to grpc
kuberesolver.RegisterInCluster()
// is same as
resolver.Register(kuberesolver.NewBuilder(nil))
// you can bring your own k8s client, below is default behaviour
client, err := kuberesolver.NewInClusterK8sClient()
resolver.Register(kuberesolver.NewBuilder(client))

// USAGE:
// if schema is 'kubernetes' then grpc will use kuberesolver to resolve addresses
cc, err := grpc.Dial("kubernetes:///service-name.namespace:portname", opts...)

An url can be one of the following, grpc naming docs

kubernetes:///service-name:8080
kubernetes:///service-name:portname
kubernetes:///service-name.namespace:8080

kubernetes://namespace/service-name:8080
kubernetes://service-name:8080/
kubernetes://service-name.namespace:8080/

Documentation

Index

• func NewBuilder(client K8sClient, schema string) resolver.Builder
• func RegisterInCluster()
• func RegisterInClusterWithSchema(schema string)
• type Address
• type Endpoints
• type Event
• type EventType
• type K8sClient
  • func NewInClusterK8sClient() (K8sClient, error)
  • func NewInsecureK8sClient(apiURL string) K8sClient
• type Metadata
• type ObjectReference
• type Port
• type Subset

Functions

func NewBuilder

func NewBuilder(client K8sClient, schema string) resolver.Builder

NewBuilder creates a kubeBuilder which is used to factory Kuberesolvers.

func RegisterInCluster

func RegisterInCluster()

RegisterInCluster registers the kuberesolver builder to grpc

func RegisterInClusterWithSchema

func RegisterInClusterWithSchema(schema string)

Types

type Address

type Address struct {
	IP        string           `json:"ip"`
	TargetRef *ObjectReference `json:"targetRef,omitempty"`
}

type Endpoints

type Endpoints struct {
	Kind       string   `json:"kind"`
	ApiVersion string   `json:"apiVersion"`
	Metadata   Metadata `json:"metadata"`
	Subsets    []Subset `json:"subsets"`
}

type Event

type Event struct {
	Type   EventType `json:"type"`
	Object Endpoints `json:"object"`
}

Event represents a single event to a watched resource.

type EventType

type EventType string

const (
	Added    EventType = "ADDED"
	Modified EventType = "MODIFIED"
	Deleted  EventType = "DELETED"
	Error    EventType = "ERROR"
)

type K8sClient

type K8sClient interface {
	Do(req *http.Request) (*http.Response, error)
	GetRequest(url string) (*http.Request, error)
	Host() string
}

K8sClient is minimal kubernetes client interface

func NewInClusterK8sClient

func NewInClusterK8sClient() (K8sClient, error)

NewInClusterK8sClient creates K8sClient if it is inside Kubernetes

func NewInsecureK8sClient

func NewInsecureK8sClient(apiURL string) K8sClient

NewInsecureK8sClient creates an insecure k8s client which is suitable to connect kubernetes api behind proxy

type Metadata

type Metadata struct {
	Name            string            `json:"name"`
	Namespace       string            `json:"namespace"`
	ResourceVersion string            `json:"resourceVersion"`
	Labels          map[string]string `json:"labels"`
}

type ObjectReference

type ObjectReference struct {
	Kind      string `json:"kind"`
	Name      string `json:"name"`
	Namespace string `json:"namespace"`
}

type Port

type Port struct {
	Name string `json:"name"`
	Port int    `json:"port"`
}

type Subset

type Subset struct {
	Addresses []Address `json:"addresses"`
	Ports     []Port    `json:"ports"`
}