// Start listening, all configuration and state is sent via messages
func Start(listener chan gotocol.Message) {
// remember the channel to talk to microservices
microservices := ribbon.MakeRouter()
dependencies := make(map[string]time.Time) // dependent services and time last updated
var parent chan gotocol.Message // remember how to talk back to creator
requestor := make(map[string]gotocol.Routetype) // remember where requests came from when responding
var name string // remember my name
eureka := make(map[string]chan gotocol.Message, 1) // service registry
hist := collect.NewHist("")
ep, _ := time.ParseDuration(archaius.Conf.EurekaPoll)
eurekaTicker := time.NewTicker(ep)
for {
select {
case msg := <-listener:
flow.Instrument(msg, name, hist)
switch msg.Imposition {
case gotocol.Hello:
if name == "" {
// if I don't have a name yet remember what I've been named
parent = msg.ResponseChan // remember how to talk to my namer
name = msg.Intention // message body is my name
hist = collect.NewHist(name)
}
case gotocol.Inform:
eureka[msg.Intention] = handlers.Inform(msg, name, listener)
case gotocol.NameDrop:
handlers.NameDrop(&dependencies, microservices, msg, name, listener, eureka)
case gotocol.Forget:
// forget a buddy
handlers.Forget(&dependencies, microservices, msg)
case gotocol.GetRequest:
// route the request on to microservices
handlers.GetRequest(msg, name, listener, &requestor, microservices)
case gotocol.GetResponse:
// return path from a request, send payload back up using saved span context - server send
handlers.GetResponse(msg, name, listener, &requestor)
case gotocol.Put:
// route the request on to a random dependency
handlers.Put(msg, name, listener, &requestor, microservices)
case gotocol.Goodbye:
for _, ch := range eureka { // tell name service I'm not going to be here
ch <- gotocol.Message{gotocol.Delete, nil, time.Now(), gotocol.NilContext, name}
}
gotocol.Message{gotocol.Goodbye, nil, time.Now(), gotocol.NilContext, name}.GoSend(parent)
return
}
case <-eurekaTicker.C: // check to see if any new dependencies have appeared
for dep, _ := range dependencies {
for _, ch := range eureka {
ch <- gotocol.Message{gotocol.GetRequest, listener, time.Now(), gotocol.NilContext, dep}
}
}
}
}
}
// Start staash, all configuration and state is sent via messages
func Start(listener chan gotocol.Message) {
microservices := ribbon.MakeRouter() // outbound routes
var caches, stores, volumes, cass, staash *ribbon.Router // subsets of the router
dependencies := make(map[string]time.Time) // dependent service names and time last updated
var parent chan gotocol.Message // remember how to talk back to creator
requestor := make(map[string]gotocol.Routetype) // remember where requests came from when responding
var name string // remember my name
eureka := make(map[string]chan gotocol.Message, 1) // service registry
hist := collect.NewHist("")
ep, _ := time.ParseDuration(archaius.Conf.EurekaPoll)
eurekaTicker := time.NewTicker(ep)
for {
select {
case msg := <-listener:
flow.Instrument(msg, name, hist)
switch msg.Imposition {
case gotocol.Hello:
if name == "" {
// if I don't have a name yet remember what I've been named
parent = msg.ResponseChan // remember how to talk to my namer
name = msg.Intention // message body is my name
hist = collect.NewHist(name)
}
case gotocol.Inform:
eureka[msg.Intention] = handlers.Inform(msg, name, listener)
case gotocol.NameDrop:
handlers.NameDrop(&dependencies, microservices, msg, name, listener, eureka, true) // true to setup cross zone routing
caches = microservices.All(CachePkg)
volumes = microservices.All(VolumePkg)
stores = microservices.All(StorePkg)
cass = microservices.All(PriamCassandraPkg)
staash = microservices.All(StaashPkg)
case gotocol.Forget:
// forget a buddy
handlers.Forget(&dependencies, microservices, msg)
caches = microservices.All(CachePkg)
volumes = microservices.All(VolumePkg)
stores = microservices.All(StorePkg)
cass = microservices.All(PriamCassandraPkg)
staash = microservices.All(StaashPkg)
case gotocol.GetRequest:
// route the request on to a cache first if configured
r := gotocol.PickRoute(requestor, msg)
if caches.Len() > 0 {
handlers.GetRequest(msg, name, listener, &requestor, caches)
r.State = cacheLookup
} else {
// route to any volumes if configured
if volumes.Len() > 0 {
handlers.GetRequest(msg, name, listener, &requestor, volumes)
r.State = volumeLookup
} else {
// route to any cassandra if configured
if cass.Len() > 0 {
handlers.GetRequest(msg, name, listener, &requestor, cass)
r.State = cassandraLookup
} else {
// route to stores if configured
if stores.Len() > 0 {
handlers.GetRequest(msg, name, listener, &requestor, stores)
r.State = storeLookup
} else {
// route to more staash layers if configured
if staash.Len() > 0 {
handlers.GetRequest(msg, name, listener, &requestor, staash)
r.State = staashLookup
}
}
}
}
}
//log.Printf("%v: %v route: %v", name, msg.Context, r)
case gotocol.GetResponse:
// return path from a request, resend or send payload back up using saved span context - server send
r := gotocol.PickRoute(requestor, msg)
if msg.Intention != "" { // we got a value, so pass it back up
handlers.GetResponse(msg, name, listener, &requestor)
} else {
switch r.State {
case cacheLookup:
if volumes.Len() > 0 {
handlers.GetRequest(msg, name, listener, &requestor, volumes)
r.State = volumeLookup
break
}
fallthrough // no volumes so look for cassandra
case volumeLookup:
if cass.Len() > 0 {
handlers.GetRequest(msg, name, listener, &requestor, cass)
r.State = cassandraLookup
break
}
fallthrough // no cassandra so look for stores
case cassandraLookup:
if stores.Len() > 0 {
handlers.GetRequest(msg, name, listener, &requestor, stores)
r.State = storeLookup
break
}
fallthrough // no stores
case storeLookup:
if staash.Len() > 0 {
handlers.GetRequest(msg, name, listener, &requestor, staash)
r.State = staashLookup
break
}
fallthrough // no staash
case staashLookup:
// ran out of options to find anything so pass empty response back up
handlers.GetResponse(msg, name, listener, &requestor)
case newRequest:
default:
}
}
case gotocol.Put:
// duplicate the request to any cache, volumes, stores, and cassandra but only to one of each type
// storage class packages sideways Replicate if configured
// to get a lossy write, configure multiple stores that don't cross replicate
handlers.Put(msg, name, listener, &requestor, caches)
handlers.Put(msg, name, listener, &requestor, cass)
handlers.Put(msg, name, listener, &requestor, staash)
handlers.Put(msg, name, listener, &requestor, stores)
msg.Intention = names.Instance(name) + "/" + msg.Intention // store to an instance specific volume namespace
handlers.Put(msg, name, listener, &requestor, volumes)
case gotocol.Goodbye:
for _, ch := range eureka { // tell name service I'm not going to be here
ch <- gotocol.Message{gotocol.Delete, nil, time.Now(), gotocol.NilContext, name}
}
gotocol.Message{gotocol.Goodbye, nil, time.Now(), gotocol.NilContext, name}.GoSend(parent)
return
}
case <-eurekaTicker.C: // check to see if any new dependencies have appeared
for dep, _ := range dependencies {
for _, ch := range eureka {
ch <- gotocol.Message{gotocol.GetRequest, listener, time.Now(), gotocol.NilContext, dep}
}
}
}
}
}