topic

Documentation

Overview

Package topic provides all functionality within arrebato regarding topics. This includes both gRPC, raft and data store interactions.

Index

• Variables
• type BoltStore
  • func NewBoltStore(db *bbolt.DB) *BoltStore
  • func (bs *BoltStore) Create(_ context.Context, t *topic.Topic) error
  • func (bs *BoltStore) Delete(_ context.Context, t string) error
  • func (bs *BoltStore) Get(ctx context.Context, name string) (*topic.Topic, error)
  • func (bs *BoltStore) List(ctx context.Context) ([]*topic.Topic, error)
• type Executor
• type GRPC
  • func NewGRPC(executor Executor, querier Querier, nodes NodeLister) *GRPC
  • func (svr *GRPC) Create(ctx context.Context, request *topicsvc.CreateRequest) (*topicsvc.CreateResponse, error)
  • func (svr *GRPC) Delete(ctx context.Context, request *topicsvc.DeleteRequest) (*topicsvc.DeleteResponse, error)
  • func (svr *GRPC) Get(ctx context.Context, request *topicsvc.GetRequest) (*topicsvc.GetResponse, error)
  • func (svr *GRPC) List(ctx context.Context, _ *topicsvc.ListRequest) (*topicsvc.ListResponse, error)
  • func (svr *GRPC) Register(registrar grpc.ServiceRegistrar, health *health.Server)
• type Handler
  • func NewHandler(manager Manager, logger hclog.Logger) *Handler
  • func (h *Handler) Create(ctx context.Context, cmd *topiccmd.CreateTopic) error
  • func (h *Handler) Delete(ctx context.Context, cmd *topiccmd.DeleteTopic) error
• type Manager
• type NodeLister
• type Querier

Variables

var (
	// ErrTopicExists is the error given when attempting to create a new topic with the same name as an existing
	// topic.
	ErrTopicExists = errors.New("topic exists")

	// ErrNoTopic is the error given when attempting to delete/query a topic that does not exist.
	ErrNoTopic = errors.New("no topic")

	// ErrNoTopicInfo is the error given when querying a topic that has incomplete/invalid data within the state.
	ErrNoTopicInfo = errors.New("no topic info")
)

Types

type BoltStore

type BoltStore struct {
	// contains filtered or unexported fields
}

The BoltStore type is responsible for querying/mutating topic data within a boltdb database.

func NewBoltStore

func NewBoltStore(db *bbolt.DB) *BoltStore

NewBoltStore returns a new instance of the BoltStore type that will manage/query topic data in a boltdb database.

func (*BoltStore) Create

func (bs *BoltStore) Create(_ context.Context, t *topic.Topic) error

Create a new topic. Returns ErrTopicExists if a topic with the same name already exists.

func (*BoltStore) Delete

func (bs *BoltStore) Delete(_ context.Context, t string) error

Delete a named topic, returns ERrNoTopic if the topic does not exist.

func (*BoltStore) Get

func (bs *BoltStore) Get(ctx context.Context, name string) (*topic.Topic, error)

Get information about a Topic by name. Returns ErrNoTopic if the topic does not exist.

func (*BoltStore) List

func (bs *BoltStore) List(ctx context.Context) ([]*topic.Topic, error)

List all known topics. Returns ErrNoTopic if the store should contain information for a topic but doesn't.

type Executor

type Executor interface {
	// Execute should perform actions corresponding to the provided command. The returned error should correspond
	// to the issue relevant to the command. For example, a command that creates a new Topic should return
	// ErrTopicExists if the topic already exists.
	Execute(ctx context.Context, cmd command.Command) error
}

The Executor interface describes types that execute commands related to Topic data.

type GRPC

type GRPC struct {
	// contains filtered or unexported fields
}

The GRPC type is a topicsvc.TopicServiceServer implementation that handles inbound gRPC requests to manage and query Topics.

func NewGRPC

func NewGRPC(executor Executor, querier Querier, nodes NodeLister) *GRPC

NewGRPC returns a new instance of the GRPC type that will modify Topic data via commands sent to the Executor and query Topic data via the Querier implementation. Node data for topic assignment will be obtained via the NodeLister implementation.

func (*GRPC) Create

func (svr *GRPC) Create(ctx context.Context, request *topicsvc.CreateRequest) (*topicsvc.CreateResponse, error)

Create a new Topic, assigning it to the node with the least number of assigned topics. Returns a codes.AlreadyExists code if the topic already exists.

func (*GRPC) Delete

func (svr *GRPC) Delete(ctx context.Context, request *topicsvc.DeleteRequest) (*topicsvc.DeleteResponse, error)

Delete an existing Topic. Returns a codes.NotFound code if the topic does not exist.

func (*GRPC) Get

func (svr *GRPC) Get(ctx context.Context, request *topicsvc.GetRequest) (*topicsvc.GetResponse, error)

Get a topic by name. Returns a codes.NotFound code if the topic does not exist, or a codes.InvalidArgument code if a topic record is found with incomplete data.

func (*GRPC) List

func (svr *GRPC) List(ctx context.Context, _ *topicsvc.ListRequest) (*topicsvc.ListResponse, error)

List all topics known to the node. Returns a codes.FailedPrecondition code if a topic record is found with incomplete data.

func (*GRPC) Register

func (svr *GRPC) Register(registrar grpc.ServiceRegistrar, health *health.Server)

Register the GRPC service onto the grpc.ServiceRegistrar.

type Handler

type Handler struct {
	// contains filtered or unexported fields
}

The Handler type is responsible for handling Topic related commands passed to an Executor implementation and modifying the state of topic data appropriately.

func NewHandler

func NewHandler(manager Manager, logger hclog.Logger) *Handler

NewHandler returns a new instance of the Handler type that will modify topic data via the provided Manager implementation.

func (*Handler) Create

func (h *Handler) Create(ctx context.Context, cmd *topiccmd.CreateTopic) error

Create the topic described in the command.

func (*Handler) Delete

func (h *Handler) Delete(ctx context.Context, cmd *topiccmd.DeleteTopic) error

Delete the topic described in the command.

type Manager

type Manager interface {
	Create(ctx context.Context, t *topic.Topic) error
	Delete(ctx context.Context, t string) error
}

The Manager interface describes types responsible for managing the state of Topics within a data store.

type NodeLister

type NodeLister interface {
	// List should return all node records in the state.
	List(ctx context.Context) ([]*nodepb.Node, error)
}

The NodeLister interface describes types that can list nodes within the cluster.

type Querier

type Querier interface {
	// Get should return the Topic corresponding to the given name. It should return ErrNoTopic if the
	// named topic does not exist. It should return ErrNoTopicInfo if incomplete topic data is found.
	Get(ctx context.Context, name string) (*topic.Topic, error)

	// List should return a slice of all Topics the node has knowledge of. It should return ErrNoTopicInfo if
	// incomplete topic data is found.
	List(ctx context.Context) ([]*topic.Topic, error)
}

The Querier interface describes types that can query Topic data from a data store.