Implement Raft in Our Service

Distributed Services with Go — by Travis Jeffery (58 / 84)

👈 What Is Raft and How Does It Work? | TOC | Multiplex to Run Multiple Services on One Por t 👉

We have a log that can write and read records on one computer. We want a distributed log that’s replicated on multiple computers, so let’s implement Raft in our service to get that.

Install Raft by running this command:

​ $ go get github.com/hashicorp/raft@v1.1.1
​ $ ​# use etcd's fork of Ben Johnson's Bolt key/value store,​
​ $ ​# which includes fixes for Go 1.14+​
​ $ go mod edit -replace github.com/hashicorp/raft-boltdb=​\​
​ github.com/travisjeffery/raft-boltdb@v1.0.0

In the internal/log directory, create a distributed.go file, beginning with this snippet:

CoordinateWithConsensus/internal/log/distributed.go

​ ​package​ log
​ 
​ ​import​ (
​         ​"bytes"​
​         ​"crypto/tls"​
​         ​"fmt"​
​         ​"io"​
​         ​"net"​
​         ​"os"​
​         ​"path/filepath"​
​         ​"time"​
​ 
​         raftboltdb ​"github.com/hashicorp/raft-boltdb"​
​         ​"google.golang.org/protobuf/proto"​
​ 
​         ​"github.com/hashicorp/raft"​
​ 
​         api ​"github.com/travisjeffery/proglog/api/v1"​
​ )
​ 
​ ​type​ DistributedLog ​struct​ {
​         config Config
​         log    *Log
​         raft   *raft.Raft
​ }
​ 
​ ​func​ NewDistributedLog(dataDir ​string​, config Config) (
​         *DistributedLog…