open-nomad/nomad/status_endpoint.go
Michael Schurter 7494a0c4fd core: remove all traces of unused protocol version
Nomad inherited protocol version numbering configuration from Consul and
Serf, but unlike those projects Nomad has never used it. Nomad's
`protocol_version` has always been `1`.

While the code is effectively unused and therefore poses no runtime
risks to leave, I felt like removing it was best because:

1. Nomad's RPC subsystem has been able to evolve extensively without
   needing to increment the version number.
2. Nomad's HTTP API has evolved extensively without increment
   `API{Major,Minor}Version`. If we want to version the HTTP API in the
   future, I doubt this is the mechanism we would choose.
3. The presence of the `server.protocol_version` configuration
   parameter is confusing since `server.raft_protocol` *is* an important
   parameter for operators to consider. Even more confusing is that
   there is a distinct Serf protocol version which is included in `nomad
   server members` output under the heading `Protocol`. `raft_protocol`
   is the *only* protocol version relevant to Nomad developers and
   operators. The other protocol versions are either deadcode or have
   never changed (Serf).
4. If we were to need to version the RPC, HTTP API, or Serf protocols, I
   don't think these configuration parameters and variables are the best
   choice. If we come to that point we should choose a versioning scheme
   based on the use case and modern best practices -- not this 6+ year
   old dead code.
2022-02-18 16:12:36 -08:00

133 lines
3.4 KiB
Go

package nomad
import (
"errors"
"fmt"
"strconv"
log "github.com/hashicorp/go-hclog"
"github.com/hashicorp/consul/agent/consul/autopilot"
"github.com/hashicorp/nomad/nomad/structs"
)
// Status endpoint is used to check on server status
type Status struct {
srv *Server
logger log.Logger
}
// Ping is used to just check for connectivity
func (s *Status) Ping(args struct{}, reply *struct{}) error {
return nil
}
// Leader is used to get the address of the leader
func (s *Status) Leader(args *structs.GenericRequest, reply *string) error {
if args.Region == "" {
args.Region = s.srv.config.Region
}
if done, err := s.srv.forward("Status.Leader", args, args, reply); done {
return err
}
leader := string(s.srv.raft.Leader())
if leader != "" {
*reply = leader
} else {
*reply = ""
}
return nil
}
// Peers is used to get all the Raft peers
func (s *Status) Peers(args *structs.GenericRequest, reply *[]string) error {
if args.Region == "" {
args.Region = s.srv.config.Region
}
if done, err := s.srv.forward("Status.Peers", args, args, reply); done {
return err
}
future := s.srv.raft.GetConfiguration()
if err := future.Error(); err != nil {
return err
}
for _, server := range future.Configuration().Servers {
*reply = append(*reply, string(server.Address))
}
return nil
}
// Members return the list of servers in a cluster that a particular server is
// aware of
func (s *Status) Members(args *structs.GenericRequest, reply *structs.ServerMembersResponse) error {
// Check node read permissions
if aclObj, err := s.srv.ResolveToken(args.AuthToken); err != nil {
return err
} else if aclObj != nil && !aclObj.AllowNodeRead() {
return structs.ErrPermissionDenied
}
serfMembers := s.srv.Members()
members := make([]*structs.ServerMember, len(serfMembers))
for i, mem := range serfMembers {
members[i] = &structs.ServerMember{
Name: mem.Name,
Addr: mem.Addr,
Port: mem.Port,
Tags: mem.Tags,
Status: mem.Status.String(),
ProtocolMin: mem.ProtocolMin,
ProtocolMax: mem.ProtocolMax,
ProtocolCur: mem.ProtocolCur,
DelegateMin: mem.DelegateMin,
DelegateMax: mem.DelegateMax,
DelegateCur: mem.DelegateCur,
}
}
*reply = structs.ServerMembersResponse{
ServerName: s.srv.config.NodeName,
ServerRegion: s.srv.config.Region,
ServerDC: s.srv.config.Datacenter,
Members: members,
}
return nil
}
// RaftStats is used by Autopilot to query the raft stats of the local server.
func (s *Status) RaftStats(args struct{}, reply *autopilot.ServerStats) error {
stats := s.srv.raft.Stats()
var err error
reply.LastContact = stats["last_contact"]
reply.LastIndex, err = strconv.ParseUint(stats["last_log_index"], 10, 64)
if err != nil {
return fmt.Errorf("error parsing server's last_log_index value: %s", err)
}
reply.LastTerm, err = strconv.ParseUint(stats["last_log_term"], 10, 64)
if err != nil {
return fmt.Errorf("error parsing server's last_log_term value: %s", err)
}
return nil
}
// HasNodeConn returns whether the server has a connection to the requested
// Node.
func (s *Status) HasNodeConn(args *structs.NodeSpecificRequest, reply *structs.NodeConnQueryResponse) error {
// Validate the args
if args.NodeID == "" {
return errors.New("Must provide the NodeID")
}
state, ok := s.srv.getNodeConn(args.NodeID)
if ok {
reply.Connected = true
reply.Established = state.Established
}
return nil
}