server.go

package main

import (
	pb "KVStore/API"
	"KVStore/SkipList"
	"KVStore/Util"
	"KVStore/WAL"
	RecordPb "KVStore/WAL/pb"
	"KVStore/errors"
	"fmt"
	"golang.org/x/net/context"
	"google.golang.org/grpc"
	"log"
	"net"
)

const (
	port = ":50051"
)

type server struct {
	skiplist *SkipList.ConcurrentSkipList
	log      *wal.Log
}

func (s *server) Get(ctx context.Context, in *pb.GetRequest) (*pb.GetReply, error) {

	key, err := util.StingTounin64(in.Key)
	if err != nil {
		return nil, err
	}

	node, result := s.skiplist.Search(key)
	if !result {
		return nil, errors.NewKeyNotFoundError()
	}
	return &pb.GetReply{Value: node.Value()}, nil
}

func (s *server) Put(ctx context.Context, in *pb.PutRequest) (*pb.PutReply, error) {

	key, err := util.StingTounin64(in.Key)
	if err != nil {
		return nil, err
	}

	value, err := util.StringToArray(in.Value)
	if err != nil {
		return nil, err
	}

	s.skiplist.Insert(key, value)

	record := &RecordPb.Record{
		Type:  1,
		Key:   in.Key,
		Value: in.Value,
	}
	s.log.AppendLog(record)

	return &pb.PutReply{IsSuccess: true}, nil
}

func (s *server) Delete(ctx context.Context, in *pb.DeleteRequest) (*pb.DeleteReply, error) {

	key, err := util.StingTounin64(in.Key)
	if err != nil {
		return nil, err
	}

	s.skiplist.Delete(key)

	record := &RecordPb.Record{
		Type: 2,
		Key:  in.Key,
	}
	s.log.AppendLog(record)

	return &pb.DeleteReply{IsSuccess: true}, nil
}

func (s *server) Scan(ctx context.Context, in *pb.ScanRequest) (*pb.ScanReply, error) {

	if in.Start < 0 || in.Limit < 1 {
		return nil, errors.NewScanParameterInvaildError()
	}
	nodes := s.skiplist.Sub(in.Start, in.Limit)
	var strs []string
	for _, node := range nodes {
		strs = append(strs, node.Value())
	}
	return &pb.ScanReply{Result: strs}, nil
}

func main() {
	lis, err := net.Listen("tcp", port)
	if err != nil {
		log.Fatal("failed to listen: %v", err)
	}
	s := grpc.NewServer()
	skipList, err := SkipList.NewConcurrentSkipList(16)
	if err != nil {
		fmt.Println(err)
	}

	server := &server{}
	server.skiplist = skipList
	server.log = wal.NewLog("data.dat")

	play := wal.NewWalReplay("data.dat")
	if play != nil {
		play.ReadAll(server.skiplist)
	}

	pb.RegisterStoreServiceServer(s, server)
	s.Serve(lis)
}