package consul import ( "fmt" "strings" "sync" "time" "github.com/hashicorp/consul/consul/state" "github.com/hashicorp/consul/consul/structs" "github.com/hashicorp/go-memdb" "github.com/hashicorp/serf/coordinate" ) // Coordinate manages queries and updates for network coordinates. type Coordinate struct { // srv is a pointer back to the server. srv *Server // updates holds pending coordinate updates for the given nodes. updates map[string]*coordinate.Coordinate // updatesLock synchronizes access to the updates map. updatesLock sync.Mutex } // NewCoordinate returns a new Coordinate endpoint. func NewCoordinate(srv *Server) *Coordinate { c := &Coordinate{ srv: srv, updates: make(map[string]*coordinate.Coordinate), } go c.batchUpdate() return c } // batchUpdate is a long-running routine that flushes pending coordinates to the // Raft log in batches. func (c *Coordinate) batchUpdate() { for { select { case <-time.After(c.srv.config.CoordinateUpdatePeriod): if err := c.batchApplyUpdates(); err != nil { c.srv.logger.Printf("[WARN] consul.coordinate: Batch update failed: %v", err) } case <-c.srv.shutdownCh: return } } } // batchApplyUpdates applies all pending updates to the Raft log in a series of // batches. func (c *Coordinate) batchApplyUpdates() error { // Grab the pending updates and release the lock so we can still handle // incoming messages. c.updatesLock.Lock() pending := c.updates c.updates = make(map[string]*coordinate.Coordinate) c.updatesLock.Unlock() // Enforce the rate limit. limit := c.srv.config.CoordinateUpdateBatchSize * c.srv.config.CoordinateUpdateMaxBatches size := len(pending) if size > limit { c.srv.logger.Printf("[WARN] consul.coordinate: Discarded %d coordinate updates", size-limit) size = limit } // Transform the map into a slice that we can feed to the Raft log in // batches. i := 0 updates := make(structs.Coordinates, size) for node, coord := range pending { if !(i < size) { break } updates[i] = &structs.Coordinate{Node: node, Coord: coord} i++ } // Apply the updates to the Raft log in batches. for start := 0; start < size; start += c.srv.config.CoordinateUpdateBatchSize { end := start + c.srv.config.CoordinateUpdateBatchSize if end > size { end = size } // We set the "safe to ignore" flag on this update type so old // servers don't crash if they see one of these. t := structs.CoordinateBatchUpdateType | structs.IgnoreUnknownTypeFlag slice := updates[start:end] resp, err := c.srv.raftApply(t, slice) if err != nil { return err } if respErr, ok := resp.(error); ok { return respErr } } return nil } // Update inserts or updates the LAN coordinate of a node. func (c *Coordinate) Update(args *structs.CoordinateUpdateRequest, reply *struct{}) (err error) { if done, err := c.srv.forward("Coordinate.Update", args, args, reply); done { return err } // Since this is a coordinate coming from some place else we harden this // and look for dimensionality problems proactively. coord, err := c.srv.serfLAN.GetCoordinate() if err != nil { return err } if !coord.IsCompatibleWith(args.Coord) { return fmt.Errorf("rejected bad coordinate: %v", args.Coord) } // Fetch the ACL token, if any, and enforce the node policy if enabled. acl, err := c.srv.resolveToken(args.Token) if err != nil { return err } if acl != nil && c.srv.config.ACLEnforceVersion8 { if !acl.NodeWrite(args.Node) { return errPermissionDenied } } // Add the coordinate to the map of pending updates. c.updatesLock.Lock() c.updates[args.Node] = args.Coord c.updatesLock.Unlock() return nil } // ListDatacenters returns the list of datacenters and their respective nodes // and the raw coordinates of those nodes (if no coordinates are available for // any of the nodes, the node list may be empty). func (c *Coordinate) ListDatacenters(args *struct{}, reply *[]structs.DatacenterMap) error { maps, err := c.srv.router.GetDatacenterMaps() if err != nil { return err } // Strip the datacenter suffixes from all the node names. for i := range maps { suffix := fmt.Sprintf(".%s", maps[i].Datacenter) for j := range maps[i].Coordinates { node := maps[i].Coordinates[j].Node maps[i].Coordinates[j].Node = strings.TrimSuffix(node, suffix) } } *reply = maps return nil } // ListNodes returns the list of nodes with their raw network coordinates (if no // coordinates are available for a node it won't appear in this list). func (c *Coordinate) ListNodes(args *structs.DCSpecificRequest, reply *structs.IndexedCoordinates) error { if done, err := c.srv.forward("Coordinate.ListNodes", args, args, reply); done { return err } return c.srv.blockingQuery(&args.QueryOptions, &reply.QueryMeta, func(ws memdb.WatchSet, state *state.Store) error { index, coords, err := state.Coordinates(ws) if err != nil { return err } reply.Index, reply.Coordinates = index, coords if err := c.srv.filterACL(args.Token, reply); err != nil { return err } return nil }) }