raftstore

type Cfg struct {
	// Name the node name in the cluster
	Name string
	// RaftAddr raft addr for exchange raft message
	RaftAddr string
	// RPCAddr the RPC address to serve requests
	RPCAddr string
	// MetadataStorage storage that to store local raft state, log, and sharding metadata
	MetadataStorage storage.MetadataStorage
	// DataStorages storages that to store application's data. Beehive will
	// select the corresponding storage according to shard id
	DataStorages []storage.DataStorage
}

type CommandReadBatch interface {
	// Add add a request to this batch, returns true if it can be executed in this batch,
	// otherwrise false
	Add(uint64, *raftcmdpb.Request, map[string]interface{}) (bool, error)
	// Execute excute the batch, and return the responses
	Execute(metapb.Shard) ([]*raftcmdpb.Response, error)
	// Reset reset the current batch for reuse
	Reset()
}

type CommandWriteBatch interface {
	// Add add a request to this batch, returns true if it can be executed in this batch,
	// otherwrise false
	Add(uint64, *raftcmdpb.Request, map[string]interface{}) (bool, *raftcmdpb.Response, error)
	// Execute excute the batch, and return the write bytes, and diff bytes that used to
	// modify the size of the current shard
	Execute(metapb.Shard) (uint64, int64, error)
	// Reset reset the current batch for reuse
	Reset()
}

type LocalCommandFunc func(metapb.Shard, *raftcmdpb.Request) (*raftcmdpb.Response, error)

type Option func(*options)

type RPC interface {
	// Start start the RPC
	Start() error
	// Stop stop the RPC
	Stop()
}

type ReadCommandFunc func(metapb.Shard, *raftcmdpb.Request, map[string]interface{}) *raftcmdpb.Response

type Router interface {
	// Start the router
	Start() error
	// SelectShard returns a shard and leader store that the key is in the range [shard.Start, shard.End).
	// If returns leader address is "", means the current shard has no leader
	SelectShard(group uint64, key []byte) (uint64, string)
	// Every do with all shards
	Every(uint64, bool, func(uint64, string))

	// LeaderAddress return leader peer store address
	LeaderAddress(uint64) string
	// RandomPeerAddress return random peer store address
	RandomPeerAddress(uint64) string
}

type ShardResource interface {
	Meta() metapb.Shard
}

type ShardStateAware interface {
	// Created the shard was created on the current store
	Created(metapb.Shard)
	// Splited the shard was splited on the current store
	Splited(metapb.Shard)
	// Destory the shard was destoryed on the current store
	Destory(metapb.Shard)
	// BecomeLeader the shard was become leader on the current store
	BecomeLeader(metapb.Shard)
	// BecomeLeader the shard was become follower on the current store
	BecomeFollower(metapb.Shard)
	// SnapshotApplied snapshot applied
	SnapshotApplied(metapb.Shard)
}

type SnapshotManager interface {
	Register(msg *raftpb.SnapshotMessage, step int) bool
	Deregister(msg *raftpb.SnapshotMessage, step int)
	Create(msg *raftpb.SnapshotMessage) error
	Exists(msg *raftpb.SnapshotMessage) bool
	WriteTo(msg *raftpb.SnapshotMessage, conn goetty.IOSession) (uint64, error)
	CleanSnap(msg *raftpb.SnapshotMessage) error
	ReceiveSnapData(msg *raftpb.SnapshotMessage) error
	Apply(msg *raftpb.SnapshotMessage) error
}

type Store interface {
	// Start the raft store
	Start()
	// Stop the raft store
	Stop()
	// Meta returns store meta
	Meta() metapb.Store
	// NewRouter returns a new router
	NewRouter() Router
	// RegisterReadFunc register read command handler
	RegisterReadFunc(uint64, ReadCommandFunc)
	// RegisterWriteFunc register write command handler
	RegisterWriteFunc(uint64, WriteCommandFunc)
	// RegisterLocalFunc register local command handler
	RegisterLocalFunc(uint64, LocalCommandFunc)
	// RegisterLocalRequestCB register local request cb to process response
	RegisterLocalRequestCB(func(*raftcmdpb.RaftResponseHeader, *raftcmdpb.Response))
	// RegisterRPCRequestCB register rpc request cb to process response
	RegisterRPCRequestCB(func(*raftcmdpb.RaftResponseHeader, *raftcmdpb.Response))
	// OnRequest receive a request, and call cb while the request is completed
	OnRequest(*raftcmdpb.Request) error
	// MetadataStorage returns a MetadataStorage of the shard group
	MetadataStorage() storage.MetadataStorage
	// DataStorage returns a DataStorage of the shard group
	DataStorageByGroup(uint64) storage.DataStorage
	// MaybeLeader returns the shard replica maybe leader
	MaybeLeader(uint64) bool
	// AddShards add shards meta on the current store, and than prophet will
	// schedule this shard replicas to other nodes.
	AddShards(...metapb.Shard) error
	// AllocID returns a uint64 id, panic if has a error
	MustAllocID() uint64
	// Prophet return current prophet instance
	Prophet() prophet.Prophet
	// CreateRPCCliendSideCodec returns the rpc codec at client side
	CreateRPCCliendSideCodec() (goetty.Decoder, goetty.Encoder)
}

type Transport interface {
	Start()
	Stop()
	Send(*raftpb.RaftMessage, *etcdraftpb.Message)
	SendingSnapshotCount() uint64
}

type WriteCommandFunc func(metapb.Shard, *raftcmdpb.Request, map[string]interface{}) (uint64, int64, *raftcmdpb.Response)