39 lines
661 B
Go
39 lines
661 B
Go
package handler
|
|
|
|
import (
|
|
"fmt"
|
|
"github.com/imkira/go-observer"
|
|
"net/http"
|
|
"strconv"
|
|
)
|
|
|
|
type Value struct {
|
|
VersionRef int
|
|
}
|
|
|
|
func SyncFactory(obs observer.Property) HandlerFunc {
|
|
return func(w http.ResponseWriter, r *http.Request) {
|
|
versionRef, err := strconv.Atoi(r.URL.Query().Get("v"))
|
|
if err != nil {
|
|
versionRef = -1
|
|
}
|
|
|
|
stream := obs.Observe()
|
|
var value Value
|
|
for {
|
|
value = stream.Value().(Value)
|
|
if value.VersionRef >= versionRef {
|
|
break
|
|
}
|
|
|
|
select {
|
|
case <-stream.Changes():
|
|
stream.Next()
|
|
}
|
|
}
|
|
|
|
w.Header().Add("Content-Type", "text/plain")
|
|
fmt.Fprintf(w, "%d (%d)\n", value.VersionRef, versionRef)
|
|
}
|
|
}
|