func StartServer(servers []string, me int) *ShardMaster {
gob.Register(Op{})
sm := new(ShardMaster)
path_parts := strings.Split(servers[me], "/")
sm.db_path = db_path + path_parts[len(path_parts)-1]
os.Remove(sm.db_path)
sm.db = dbaccess.GetDatabase(sm.db_path)
// Put my index
sm.db.PutInt(METADATA, "me", me)
sm.me = me
// Enter peers
sm.db.PutStringList(METADATA, "servers", servers)
first_conf := new(Config)
first_conf.Groups = map[int64][]string{}
sm.DBPutConfig(0, first_conf)
sm.db.PutInt(METADATA, "num_configs", 1)
rpcs := rpc.NewServer()
rpcs.Register(sm)
sm.px = paxos.Make(servers, me, rpcs)
FinishStartServer(sm, servers, me, rpcs)
return sm
}
func StartServerFromDB(me string) *ShardMaster {
gob.Register(Op{})
sm := new(ShardMaster)
path_parts := strings.Split(me, "/")
sm.db_path = db_path + path_parts[len(path_parts)-1]
sm.db = dbaccess.GetDatabase(sm.db_path)
me_index, me_exists := sm.db.GetInt(METADATA, "me")
if !me_exists {
log.Fatal("couldn't find me, start from DB")
}
stored_servers, servers_exists := sm.db.GetStringList(METADATA, "servers")
if !servers_exists {
log.Fatal("couldn't find servers start from DB")
}
_, val_exists := sm.db.GetInt(METADATA, "num_configs")
if !val_exists {
log.Fatal("DB not consistent")
}
rpcs := rpc.NewServer()
rpcs.Register(sm)
sm.px = paxos.MakeFromDB(stored_servers[me_index], rpcs)
FinishStartServer(sm, stored_servers, me_index, rpcs)
return sm
}
func Make(peers []string, me int, rpcs *rpc.Server) *Paxos {
px := &Paxos{}
path_parts := strings.Split(peers[me], "/")
px.db_path = db_path + path_parts[len(path_parts)-1]
os.Remove(px.db_path)
px.db = dbaccess.GetDatabase(px.db_path)
px.FreshStart(peers, me)
FinishMake(px, rpcs)
return px
}
func MakeFromDB(me string, rpcs *rpc.Server) *Paxos {
px := &Paxos{}
path_parts := strings.Split(me, "/")
px.db_path = db_path + path_parts[len(path_parts)-1]
px.db = dbaccess.GetDatabase(px.db_path)
did_restore := px.TryRestoreFromDisk()
if !did_restore {
log.Fatal("RESTORE FROM DB FAILED")
}
FinishMake(px, rpcs)
return px
}