kvraft

Documentation

Index

• Constants
• func DPrintf(format string, a ...interface{}) (n int, err error)
• type Clerk
  • func MakeClerk(servers []*labrpc.ClientEnd) *Clerk
  • func (ck *Clerk) Append(key string, value string)
  • func (ck *Clerk) Get(key string) string
  • func (ck *Clerk) Put(key string, value string)
  • func (ck *Clerk) PutAppend(key string, value string, op string)
• type ClerkMsgId
• type Err
• type ExeResult
• type GetArgs
• type GetReply
• type KVServer
  • func StartKVServer(servers []*labrpc.ClientEnd, me int, persister *raft.Persister, ...) *KVServer
  • func (kv *KVServer) Get(args *GetArgs, reply *GetReply)
  • func (kv *KVServer) GetRf() *raft.Raft
  • func (kv *KVServer) Kill()
  • func (kv *KVServer) PutAppend(args *PutAppendArgs, reply *PutAppendReply)
• type Method
• type Op
• type PutAppendArgs
• type PutAppendReply
• type TypeClientId
• type TypeOpId

Constants

const (
	OK             = "OK"
	ErrNoKey       = "ErrNoKey"
	ErrWrongLeader = "ErrWrongLeader"
	ErrTimeout     = "ErrTimeout"
)

const (
	GET    = "Get"
	PUT    = "Put"
	APPEND = "Append"
)

const Debug = 0

const (
	TryNextLeaderInterval = time.Millisecond * 20
)

const WaitOpTimeOut = time.Millisecond * 500

Functions

func DPrintf

func DPrintf(format string, a ...interface{}) (n int, err error)

Types

type Clerk

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

func MakeClerk

func MakeClerk(servers []*labrpc.ClientEnd) *Clerk

func (*Clerk) Append

func (ck *Clerk) Append(key string, value string)

func (*Clerk) Get

func (ck *Clerk) Get(key string) string

fetch the current value for a key. returns "" if the key does not exist. keeps trying forever in the face of all other errors.

you can send an RPC with code like this: ok := ck.servers[i].Call("KVServer.Get", &args, &reply)

the types of args and reply (including whether they are pointers) must match the declared types of the RPC handler function's arguments. and reply must be passed as a pointer.

func (*Clerk) Put

func (ck *Clerk) Put(key string, value string)

func (*Clerk) PutAppend

func (ck *Clerk) PutAppend(key string, value string, op string)

shared by Put and Append.

you can send an RPC with code like this: ok := ck.servers[i].Call("KVServer.PutAppend", &args, &reply)

the types of args and reply (including whether they are pointers) must match the declared types of the RPC handler function's arguments. and reply must be passed as a pointer.

type ClerkMsgId

type ClerkMsgId int64

type Err

type Err string

type ExeResult

type ExeResult struct {
	Err   Err
	Value string
}

type GetArgs

type GetArgs struct {
	Key string
	// You'll have to add definitions here.
	ClientId TypeClientId
	MsgId    ClerkMsgId
}

type GetReply

type GetReply struct {
	Err   Err
	Value string
}

type KVServer

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

func StartKVServer

func StartKVServer(servers []*labrpc.ClientEnd, me int, persister *raft.Persister, maxraftstate int) *KVServer

servers[] contains the ports of the set of servers that will cooperate via Raft to form the fault-tolerant key/value service. me is the index of the current server in servers[]. the k/v server should store snapshots through the underlying Raft implementation, which should call persister.SaveStateAndSnapshot() to atomically save the Raft state along with the snapshot. the k/v server should snapshot when Raft's saved state exceeds maxraftstate bytes, in order to allow Raft to garbage-collect its log. if maxraftstate is -1, you don't need to snapshot. StartKVServer() must return quickly, so it should start goroutines for any long-running work.

func (*KVServer) Get

func (kv *KVServer) Get(args *GetArgs, reply *GetReply)

func (*KVServer) GetRf

func (kv *KVServer) GetRf() *raft.Raft

func (*KVServer) Kill

func (kv *KVServer) Kill()

the tester calls Kill() when a KVServer instance won't be needed again. for your convenience, we supply code to set rf.dead (without needing a lock), and a killed() method to test rf.dead in long-running loops. you can also add your own code to Kill(). you're not required to do anything about this, but it may be convenient (for example) to suppress debug output from a Kill()ed instance.

func (*KVServer) PutAppend

func (kv *KVServer) PutAppend(args *PutAppendArgs, reply *PutAppendReply)

type Method

type Method string

type Op

type Op struct {
	Method Method
	Key    string
	Value  string

	ClientId TypeClientId
	MsgId    ClerkMsgId

	// ServerId + OpId is unique for each op
	ServerId int
	OpId     TypeOpId
}

type PutAppendArgs

type PutAppendArgs struct {
	Key   string
	Value string
	Op    string // "Put" or "Append"
	// You'll have to add definitions here.
	// Field names must start with capital letters,
	// otherwise RPC will break.
	ClientId TypeClientId
	MsgId    ClerkMsgId
}

Put or Append

type PutAppendReply

type PutAppendReply struct {
	Err Err
}

type TypeClientId

type TypeClientId int64

type TypeOpId

type TypeOpId int64