import "container/list"
import "encoding/json"
+import "expvar"
+import "flag"
import "log"
import "net/http"
+import "strconv"
import "time"
+var port = flag.Int("port", 21059, "Port to listen on")
+
+var speak_count = expvar.NewInt("speak_count")
+var fetch_count = expvar.NewInt("fetch_count")
+var fetch_wait_count = expvar.NewInt("fetch_wait_count")
+var fetch_wake_count = expvar.NewInt("fetch_wake_count")
+
type Message struct {
Time time.Time
+ ID string
Text string
}
}
type Store struct {
- Add chan Message
- Get chan StoreRequest
+ Add chan *Message
+ Get chan *StoreRequest
}
// TODO: Monotonic clock
message_count := 0
max_messages := 1000
waiting := list.New()
+main:
for {
select {
- case new_message := <-store.Add:
- messages.PushBack(new_message)
+ case new_message, ok := <-store.Add:
+ if !ok {
+ break main
+ }
+ speak_count.Add(1)
for waiter := waiting.Front(); waiter != nil; waiter = waiter.Next() {
- waiter.Value.(StoreRequest).Messages <- []Message{new_message}
- close(waiter.Value.(StoreRequest).Messages)
+ waiter.Value.(*StoreRequest).Messages <- []Message{*new_message}
+ close(waiter.Value.(*StoreRequest).Messages)
+ fetch_wake_count.Add(1)
}
waiting.Init()
+ messages.PushBack(new_message)
if message_count < max_messages {
message_count++
} else {
messages.Remove(messages.Front())
}
- case request := <-store.Get:
- if messages.Back() == nil || !request.StartTime.Before(messages.Back().Value.(Message).Time) {
+ case request, ok := <-store.Get:
+ if !ok {
+ break main
+ }
+ fetch_count.Add(1)
+ if messages.Back() == nil || !request.StartTime.Before(messages.Back().Value.(*Message).Time) {
waiting.PushBack(request)
+ fetch_wait_count.Add(1)
} else {
start := messages.Back()
response_size := 1
- if messages.Front().Value.(Message).Time.After(request.StartTime) {
+ if messages.Front().Value.(*Message).Time.After(request.StartTime) {
start = messages.Front()
response_size = message_count
} else {
- for start.Prev().Value.(Message).Time.After(request.StartTime) {
+ for start.Prev().Value.(*Message).Time.After(request.StartTime) {
start = start.Prev()
response_size++
}
}
response_messages := make([]Message, 0, response_size)
for m := start; m != nil; m = m.Next() {
- response_messages = append(response_messages, m.Value.(Message))
+ response_messages = append(response_messages, *m.Value.(*Message))
}
request.Messages <- response_messages
}
}
func start_store() Store {
- store := Store{make(chan Message, 20), make(chan StoreRequest, 20)}
+ store := Store{make(chan *Message, 20), make(chan *StoreRequest, 20)}
go manage_store(store)
return store
}
}
}
messages_from_store := make(chan []Message, 1)
- store.Get <- StoreRequest{since, messages_from_store}
+ store.Get <- &StoreRequest{since, messages_from_store}
json_encoded, err := json.Marshal(<-messages_from_store)
if err != nil {
})
http.HandleFunc("/speak", func(w http.ResponseWriter, r *http.Request) {
- store.Add <- Message{time.Now(), r.FormValue("text")}
+ store.Add <- &Message{
+ time.Now(),
+ r.FormValue("id"),
+ r.FormValue("text")}
})
- log.Fatal(http.ListenAndServe(":8080", nil))
+ log.Fatal(http.ListenAndServe(":"+strconv.Itoa(*port), nil))
}
func main() {