open-nomad/nomad/operator_endpoint.go

108 lines
3.3 KiB
Go

package nomad
import (
"fmt"
"net"
"github.com/hashicorp/nomad/nomad/structs"
"github.com/hashicorp/raft"
"github.com/hashicorp/serf/serf"
)
// Operator endpoint is used to perform low-level operator tasks for Nomad.
type Operator struct {
srv *Server
}
// RaftGetConfiguration is used to retrieve the current Raft configuration.
func (op *Operator) RaftGetConfiguration(args *structs.GenericRequest, reply *structs.RaftConfigurationResponse) error {
if done, err := op.srv.forward("Operator.RaftGetConfiguration", args, args, reply); done {
return err
}
// We can't fetch the leader and the configuration atomically with
// the current Raft API.
future := op.srv.raft.GetConfiguration()
if err := future.Error(); err != nil {
return err
}
// Index the Nomad information about the servers.
serverMap := make(map[raft.ServerAddress]serf.Member)
for _, member := range op.srv.serf.Members() {
valid, parts := isNomadServer(member)
if !valid {
continue
}
addr := (&net.TCPAddr{IP: member.Addr, Port: parts.Port}).String()
serverMap[raft.ServerAddress(addr)] = member
}
// Fill out the reply.
leader := op.srv.raft.Leader()
reply.Index = future.Index()
for _, server := range future.Configuration().Servers {
node := "(unknown)"
if member, ok := serverMap[server.Address]; ok {
node = member.Name
}
entry := &structs.RaftServer{
ID: server.ID,
Node: node,
Address: server.Address,
Leader: server.Address == leader,
Voter: server.Suffrage == raft.Voter,
}
reply.Servers = append(reply.Servers, entry)
}
return nil
}
// RaftRemovePeerByAddress is used to kick a stale peer (one that it in the Raft
// quorum but no longer known to Serf or the catalog) by address in the form of
// "IP:port". The reply argument is not used, but it required to fulfill the RPC
// interface.
func (op *Operator) RaftRemovePeerByAddress(args *structs.RaftPeerByAddressRequest, reply *struct{}) error {
if done, err := op.srv.forward("Operator.RaftRemovePeerByAddress", args, args, reply); done {
return err
}
// Since this is an operation designed for humans to use, we will return
// an error if the supplied address isn't among the peers since it's
// likely they screwed up.
{
future := op.srv.raft.GetConfiguration()
if err := future.Error(); err != nil {
return err
}
for _, s := range future.Configuration().Servers {
if s.Address == args.Address {
goto REMOVE
}
}
return fmt.Errorf("address %q was not found in the Raft configuration",
args.Address)
}
REMOVE:
// The Raft library itself will prevent various forms of foot-shooting,
// like making a configuration with no voters. Some consideration was
// given here to adding more checks, but it was decided to make this as
// low-level and direct as possible. We've got ACL coverage to lock this
// down, and if you are an operator, it's assumed you know what you are
// doing if you are calling this. If you remove a peer that's known to
// Serf, for example, it will come back when the leader does a reconcile
// pass.
future := op.srv.raft.RemovePeer(args.Address)
if err := future.Error(); err != nil {
op.srv.logger.Printf("[WARN] nomad.operator: Failed to remove Raft peer %q: %v",
args.Address, err)
return err
}
op.srv.logger.Printf("[WARN] nomad.operator: Removed Raft peer %q", args.Address)
return nil
}