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 Err
• 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) Kill()
  • func (kv *KVServer) PutAppend(args *PutAppendArgs, reply *PutAppendReply)
• type Op
• type OpContext
• type PutAppendArgs
• type PutAppendReply

Constants

const (
	OK             = "OK"
	ErrNoKey       = "ErrNoKey"       // 针对get请求进行处理，表示没有对应的key
	ErrWrongLeader = "ErrWrongLeader" // 找到错误的leader
)

const Debug = 0

Functions

func DPrintf

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

Types

type Clerk

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

Clerk对应client，本身负责发送Get、Append、Put请求

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 Err

type Err string

type GetArgs

type GetArgs struct {
	Key string
	// You'll have to add definitions here.
	ClientId int64
	SeqId    int64
}

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) 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 Op

type Op struct {
	// Your definitions here.
	// Field names must start with capital letters,
	// otherwise RPC will break.
	Index    int    // 写入raft时的index
	Term     int    // 写入raft时的term
	Type     string // 操作类型，put，append，get
	Key      string
	Value    string // Get操作无需管理
	SeqId    int64  // 记录发送号
	ClientId int64  // 记录client号
}

对传进来的原始op进行封装

type OpContext

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

记录apply的op对应的结果

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 int64 // 记录发送请求的client
	SeqId    int64 // 记录该client发送的id
}

Put or Append

type PutAppendReply

type PutAppendReply struct {
	Err Err
}