Finagle Websocket

Websockets support for Finagle

Status

This project is inactive. While we are keep it up to date with new Finagle releases, it is not currently being actively used or developed. If you're using Finagle Websocket and would be interested in discussing co-ownership, please file an issue.

Using websockets

Adding dependencies

Maven

<repositories>
  <repository>
    <id>com.github.sprsquish</id>
    <url>https://raw.github.com/sprsquish/mvn-repo/master/</url>
    <layout>default</layout>
  </repository>
</repositories>

<dependency>
  <groupId>com.github.sprsquish</groupId>
  <artifactId>finagle-websockets_2.9.2</artifactId>
  <version>6.8.1</version>
  <scope>compile</scope>
</dependency>

sbt

resolvers += "com.github.sprsquish" at "https://raw.github.com/sprsquish/mvn-repo/master"

"com.github.sprsquish" %% "finagle-websockets" % "6.8.1"

Example

The following client and server can be run by pasting the code into sbt console. The client sends "1" over to the server. The server responds by translating the numeral into an word (mostly). When the client receives this word, it will send back a number which represents the length of characters of the received word.

Client

import com.twitter.concurrent.AsyncStream
import com.twitter.conversions.time._
import com.twitter.finagle.Websocket
import com.twitter.finagle.util.DefaultTimer
import com.twitter.finagle.websocket.{Frame, Request}
import com.twitter.util.Promise
import java.net.URI

implicit val timer = DefaultTimer.twitter

// Responds to messages from the server.
def handler(messages: AsyncStream[Frame]): AsyncStream[Frame] =
  messages.flatMap {
    case Frame.Text(message) =>
      // Print the received message.
      println(message)

      AsyncStream.fromFuture(
        // Sleep for a second...
        Future.sleep(1.second).map { _ =>
          // ... and then send a message to the server.
          Frame.Text(message.length.toString)
        })

    case _ => AsyncStream.of(Frame.Text("??"))
  }

val incoming = new Promise[AsyncStream[Frame]]
val outgoing =
  Frame.Text("1") +:: handler(
    AsyncStream.fromFuture(incoming).flatten)

val client = Websocket.client.newService(":14000")
val req = Request(new URI("/"), Map.empty, null, outgoing)

// Take the messages of the response and fulfill `incoming`.
client(req).map(_.messages).proxyTo(incoming)

Server

import com.twitter.concurrent.AsyncStream
import com.twitter.finagle.{Service, Websocket}
import com.twitter.finagle.websocket.{Frame, Request, Response}
import com.twitter.util.Future

// A server that when given a number, responds with a word (mostly).
def handler(messages: AsyncStream[Frame]): AsyncStream[Frame] = {
  messages.map {
    case Frame.Text("1") => Frame.Text("one")
    case Frame.Text("2") => Frame.Text("two")
    case Frame.Text("3") => Frame.Text("three")
    case Frame.Text("4") => Frame.Text("cuatro")
    case Frame.Text("5") => Frame.Text("five")
    case Frame.Text("6") => Frame.Text("6")
    case _ => Frame.Text("??")
  }
}

Websocket.serve(":14000", new Service[Request, Response] {
  def apply(req: Request): Future[Response] =
    Future.value(Response(handler(req.messages)))
})