func (r Router) appendToRoutingTable(path Path, ctx bh.RcvContext) (Route,
error) {
from, err := path.From()
if err != nil {
return Route{}, err
}
to, err := path.To()
if err != nil {
return Route{}, err
}
tbl := r.routingTable(from, ctx)
route, ok := tbl[to]
if !ok {
route = Route{
To: to,
}
}
if route.Contains(path) {
return route, errors.New("Route already has the path")
}
if err := route.AddPath(path); err != nil {
return route, err
}
if route.IsShortestPath(path) {
route.Updates = append(route.Updates, path)
// Indication of an update in bee local.
ctx.SetBeeLocal(true)
}
tbl[to] = route
ctx.Dict(routeDict).Put(from.Key(), tbl)
return route, nil
}
// Rcv handles both Discovery and Advertisement messages.
func (r Router) Rcv(msg bh.Msg, ctx bh.RcvContext) error {
switch d := msg.Data().(type) {
case Discovery:
if err := r.appendNieghbor(Edge(d), ctx); err != nil {
return err
}
if Edge(d).To.Endhost {
adv, err := Path{}.Append(Edge(d).From, Edge(d).To)
if err != nil {
return err
}
ctx.Emit(Advertisement(adv))
}
// Indication of an update.
ctx.SetBeeLocal(true)
case Advertisement:
path := Path(d)
if to, err := path.To(); err != nil || !to.Endhost {
return errors.New("Route is not towards an end-host")
}
if _, err := r.appendToRoutingTable(path, ctx); err != nil {
return err
}
case Timeout:
if !ctx.BeeLocal().(bool) {
return nil
}
ctx.SetBeeLocal(false)
type keyTable struct {
k string
t RoutingTable
}
var entries []keyTable
ctx.Dict(routeDict).ForEach(func(k string, v interface{}) bool {
tbl := v.(RoutingTable)
from := Node{
ID: string(k),
}
for to, route := range tbl {
if len(route.Updates) == 0 {
continue
}
shortestPaths := route.ShortestPaths()
glog.V(1).Infof("Shortest paths: %v", shortestPaths)
for _, p := range route.Updates {
if !route.IsShortestPath(p) {
continue
}
for _, n := range r.neighbors(from, ctx) {
if np, err := p.Prepend(n.From); err == nil {
ctx.Emit(Advertisement(np))
}
}
}
route.Updates = nil
tbl[to] = route
}
entries = append(entries, keyTable{k, tbl})
return true
})
for _, e := range entries {
ctx.Dict(routeDict).Put(e.k, e.t)
}
}
return nil
}