update

remote-host.go

@@ -0,0 +1,94 @@
+package main
+
+import (
+	"fmt"
+	"log"
+	"strings"
+)
+
+type RemoteHost struct {
+	*Client
+	Host        string
+	MissedPings int
+}
+
+func (h *RemoteHost) IsHealthy() bool {
+	return !h.Dead && h.MissedPings < 3
+}
+
+func (h *RemoteHost) Initialize(p *SyncedPool) {
+
+	ids, err := h.GetCartMappings()
+	if err != nil {
+		log.Printf("Error getting remote mappings: %v\n", err)
+		return
+	}
+	log.Printf("Remote %s has %d grains\n", h.Host, len(ids))
+	p.mu.Lock()
+	local := 0
+	remoteNo := 0
+	for _, id := range ids {
+		go p.SpawnRemoteGrain(id, h.Host)
+		remoteNo++
+	}
+	log.Printf("Removed %d local grains, added %d remote grains\n", local, remoteNo)
+	p.mu.Unlock()
+	go p.Negotiate()
+
+}
+
+func (h *RemoteHost) Ping() error {
+	_, err := h.Call(Ping, Pong, []byte{})
+
+	if err != nil {
+		h.MissedPings++
+		log.Printf("Error pinging remote %s, missed pings: %d", h.Host, h.MissedPings)
+
+	} else {
+		h.MissedPings = 0
+	}
+	return err
+}
+
+func (h *RemoteHost) Negotiate(knownHosts []string) ([]string, error) {
+	reply, err := h.Call(RemoteNegotiate, RemoteNegotiateResponse, []byte(strings.Join(knownHosts, ";")))
+
+	if err != nil {
+		return nil, err
+	}
+	if reply.StatusCode != 200 {
+		return nil, fmt.Errorf("remote returned error on negotiate: %s", string(reply.Data))
+	}
+
+	return strings.Split(string(reply.Data), ";"), nil
+}
+
+func (g *RemoteHost) GetCartMappings() ([]CartId, error) {
+	reply, err := g.Call(GetCartIds, CartIdsResponse, []byte{})
+	if err != nil {
+		return nil, err
+	}
+	if reply.StatusCode != 200 {
+		log.Printf("Remote returned error on get cart mappings: %s", string(reply.Data))
+		return nil, fmt.Errorf("remote returned error: %s", string(reply.Data))
+	}
+	parts := strings.Split(string(reply.Data), ";")
+	ids := make([]CartId, 0, len(parts))
+	for _, p := range parts {
+		ids = append(ids, ToCartId(p))
+	}
+	return ids, nil
+}
+
+func (r *RemoteHost) ConfirmChange(id CartId, host string) error {
+	reply, err := r.Call(RemoteGrainChanged, AckChange, []byte(fmt.Sprintf("%s;%s", id, host)))
+
+	if err != nil {
+		return err
+	}
+	if string(reply.Data) != "ok" {
+		return fmt.Errorf("remote grain change failed %s", string(reply.Data))
+	}
+
+	return nil
+}