initial add hashicorp raft

weed/server/raft_hashicorp.go

@@ -0,0 +1,98 @@
+package weed_server
+
+// https://yusufs.medium.com/creating-distributed-kv-database-by-implementing-raft-consensus-using-golang-d0884eef2e28
+// https://github.com/Jille/raft-grpc-example/blob/cd5bcab0218f008e044fbeee4facdd01b06018ad/application.go#L18
+
+import (
+	"context"
+	"fmt"
+	transport "github.com/Jille/raft-grpc-transport"
+	"github.com/chrislusf/seaweedfs/weed/glog"
+	"github.com/hashicorp/raft"
+	boltdb "github.com/hashicorp/raft-boltdb"
+	"google.golang.org/grpc"
+	"math/rand"
+	"os"
+	"path/filepath"
+	"time"
+)
+
+func NewHashicorpRaftServer(ctx context.Context, option *RaftServerOption) (*RaftServer, error) {
+	s := &RaftServer{
+		peers:      option.Peers,
+		serverAddr: option.ServerAddr,
+		dataDir:    option.DataDir,
+		topo:       option.Topo,
+	}
+
+	c := raft.DefaultConfig()
+	c.LocalID = raft.ServerID(s.serverAddr) // TODO maybee the IP:port address will change
+	c.HeartbeatTimeout = time.Duration(float64(option.HeartbeatInterval) * (rand.Float64()*0.25 + 1))
+	c.ElectionTimeout = option.ElectionTimeout
+	if glog.V(4) {
+		c.Logger.SetLevel(1)
+	} else if glog.V(3) {
+		c.Logger.SetLevel(2)
+	} else if glog.V(2) {
+		c.Logger.SetLevel(3)
+	} else if glog.V(1) {
+		c.Logger.SetLevel(4)
+	} else if glog.V(0) {
+		c.Logger.SetLevel(5)
+	}
+
+	baseDir := s.dataDir
+
+	ldb, err := boltdb.NewBoltStore(filepath.Join(baseDir, "logs.dat"))
+	if err != nil {
+		return nil, fmt.Errorf(`boltdb.NewBoltStore(%q): %v`, filepath.Join(baseDir, "logs.dat"), err)
+	}
+
+	sdb, err := boltdb.NewBoltStore(filepath.Join(baseDir, "stable.dat"))
+	if err != nil {
+		return nil, fmt.Errorf(`boltdb.NewBoltStore(%q): %v`, filepath.Join(baseDir, "stable.dat"), err)
+	}
+
+	fss, err := raft.NewFileSnapshotStore(baseDir, 3, os.Stderr)
+	if err != nil {
+		return nil, fmt.Errorf(`raft.NewFileSnapshotStore(%q, ...): %v`, baseDir, err)
+	}
+
+	// s.GrpcServer = raft.NewGrpcServer(s.raftServer)
+	s.TransportManager = transport.New(raft.ServerAddress(s.serverAddr), []grpc.DialOption{option.GrpcDialOption})
+
+	stateMachine := StateMachine{topo: option.Topo}
+	r, err := raft.NewRaft(c, &stateMachine, ldb, sdb, fss, s.TransportManager.Transport())
+	if err != nil {
+		return nil, fmt.Errorf("raft.NewRaft: %v", err)
+	}
+
+	if option.RaftBootstrap {
+		cfg := raft.Configuration{
+			Servers: []raft.Server{
+				{
+					Suffrage: raft.Voter,
+					ID:       c.LocalID,
+					Address:  raft.ServerAddress(s.serverAddr),
+				},
+			},
+		}
+		// Add known peers to bootstrap
+		for _, node := range option.Peers {
+			if node == option.ServerAddr {
+				continue
+			}
+			cfg.Servers = append(cfg.Servers, raft.Server{
+				Suffrage: raft.Voter,
+				ID:       raft.ServerID(node),
+				Address:  raft.ServerAddress(node),
+			})
+		}
+		f := r.BootstrapCluster(cfg)
+		if err := f.Error(); err != nil {
+			return nil, fmt.Errorf("raft.Raft.BootstrapCluster: %v", err)
+		}
+	}
+
+	return s, nil
+}