我有以下服务器端的播放代码,以便为 HTML5 EventSources 提供端点。
package controllers
import scala.util.matching
import play.api.mvc._
import play.api.libs.json.JsValue
import play.api.libs.iteratee.{Concurrent, Enumeratee}
import play.api.libs.EventSource
import play.api.libs.concurrent.Execution.Implicits._
object Application extends Controller {
/** Central hub for distributing chat messages */
val (eventOut, eventChannel) = Concurrent.broadcast[JsValue]
/** Enumeratee for filtering messages based on eventSpec */
def filter(eventSpec: String) = Enumeratee.filter[JsValue] {
json: JsValue => ("(?i)" + eventSpec).r.pattern.matcher((json \ "eventSpec").as[String]).matches
}
/** Enumeratee for detecting disconnect of SSE stream */
def connDeathWatch(addr: String): Enumeratee[JsValue, JsValue] =
Enumeratee.onIterateeDone{ () => println(addr + " - SSE disconnected") }
/** Controller action serving activity based on eventSpec */
def events = Action { req =>
println(req.remoteAddress + " - connected and subscribed for '" + eventSpec +"'")
Ok.feed(eventOut
&> filter(eventSpec)
&> Concurrent.buffer(50)
&> connDeathWatch(req.remoteAddress)
&> EventSource()
).as("text/event-stream").withHeaders(
"Access-Control-Allow-Origin" -> "*",
"Access-Control-Allow-Methods" -> "GET",
"Access-Control-Allow-Headers" -> "Content-Type"
)
}
}
我的路由看起来像这样:
GET /events controllers.Application.events
这个服务器在Chrome浏览器通过EventSource对象连接时完全正常。由于IE不支持EventSources,我正在使用此 polyfill库。现在问题来了:IE正确地订阅事件,因为我可以看到'已连接和已订阅'的日志信息,但是一旦事件应该传递到此连接时,它就会记录'SSE已断开连接'。我错过了什么?需要添加一些HTTP头吗?