+str #17310: Basic framing support

akka-docs-dev/rst/scala/code/docs/stream/cookbook/RecipeParseLines.scala

@@ -20,9 +20,10 @@ class RecipeParseLines extends RecipeSpec {
         ByteString("\nHello Akka!\r\nHello Streams!"),
         ByteString("\r\n\r\n")))
 
-      import RecipeParseLines._
-
-      val linesStream = rawData.transform(() => parseLines("\r\n", 100))
+      //#parse-lines
+      import akka.stream.io.Framing
+      val linesStream = rawData.via(Framing.lines("\r\n", maximumLineBytes = 100))
+      //#parse-lines
 
       Await.result(linesStream.grouped(10).runWith(Sink.head), 3.seconds) should be(List(
         "Hello World\r!",
@@ -34,58 +35,3 @@ class RecipeParseLines extends RecipeSpec {
   }
 
 }
-
-object RecipeParseLines {
-
-  import akka.stream.stage._
-
-  //#parse-lines
-  def parseLines(separator: String, maximumLineBytes: Int) =
-    new StatefulStage[ByteString, String] {
-      private val separatorBytes = ByteString(separator)
-      private val firstSeparatorByte = separatorBytes.head
-      private var buffer = ByteString.empty
-      private var nextPossibleMatch = 0
-
-      def initial = new State {
-        override def onPush(chunk: ByteString, ctx: Context[String]): SyncDirective = {
-          buffer ++= chunk
-          if (buffer.size > maximumLineBytes)
-            ctx.fail(new IllegalStateException(s"Read ${buffer.size} bytes " +
-              s"which is more than $maximumLineBytes without seeing a line terminator"))
-          else emit(doParse(Vector.empty).iterator, ctx)
-        }
-
-        @tailrec
-        private def doParse(parsedLinesSoFar: Vector[String]): Vector[String] = {
-          val possibleMatchPos = buffer.indexOf(firstSeparatorByte, from = nextPossibleMatch)
-          if (possibleMatchPos == -1) {
-            // No matching character, we need to accumulate more bytes into the buffer
-            nextPossibleMatch = buffer.size
-            parsedLinesSoFar
-          } else if (possibleMatchPos + separatorBytes.size > buffer.size) {
-            // We have found a possible match (we found the first character of the terminator
-            // sequence) but we don't have yet enough bytes. We remember the position to
-            // retry from next time.
-            nextPossibleMatch = possibleMatchPos
-            parsedLinesSoFar
-          } else {
-            if (buffer.slice(possibleMatchPos, possibleMatchPos + separatorBytes.size)
-              == separatorBytes) {
-              // Found a match
-              val parsedLine = buffer.slice(0, possibleMatchPos).utf8String
-              buffer = buffer.drop(possibleMatchPos + separatorBytes.size)
-              nextPossibleMatch -= possibleMatchPos + separatorBytes.size
-              doParse(parsedLinesSoFar :+ parsedLine)
-            } else {
-              nextPossibleMatch += 1
-              doParse(parsedLinesSoFar)
-            }
-          }
-
-        }
-      }
-    }
-  //#parse-lines
-
-}

akka-docs-dev/rst/scala/code/docs/stream/io/StreamTcpDocSpec.scala

@@ -41,11 +41,13 @@ class StreamTcpDocSpec extends AkkaSpec {
         Tcp().bind(localhost.getHostName, localhost.getPort) // TODO getHostString in Java7
 
       //#echo-server-simple-handle
+      import akka.stream.io.Framing
+
       connections runForeach { connection =>
         println(s"New connection from: ${connection.remoteAddress}")
 
         val echo = Flow[ByteString]
-          .transform(() => RecipeParseLines.parseLines("\n", maximumLineBytes = 256))
+          .via(Framing.lines("\n", maximumLineBytes = 256, allowTruncation = false))
           .map(_ + "!!!\n")
           .map(ByteString(_))
 
@@ -60,7 +62,9 @@ class StreamTcpDocSpec extends AkkaSpec {
     val connections = Tcp().bind(localhost.getHostName, localhost.getPort) // TODO getHostString in Java7
     val serverProbe = TestProbe()
 
+    import akka.stream.io.Framing
     //#welcome-banner-chat-server
+
     connections runForeach { connection =>
 
       val serverLogic = Flow() { implicit b =>
@@ -81,7 +85,7 @@ class StreamTcpDocSpec extends AkkaSpec {
 
         val welcome = Source.single(ByteString(welcomeMsg))
         val echo = b.add(Flow[ByteString]
-          .transform(() => RecipeParseLines.parseLines("\n", maximumLineBytes = 256))
+          .via(Framing.lines("\n", maximumLineBytes = 256, allowTruncation = false))
           //#welcome-banner-chat-server
           .map { command ⇒ serverProbe.ref ! command; command }
           //#welcome-banner-chat-server
@@ -101,6 +105,7 @@ class StreamTcpDocSpec extends AkkaSpec {
       connection.handleWith(serverLogic)
     }
 
+    import akka.stream.io.Framing
     //#welcome-banner-chat-server
 
     val input = new AtomicReference("Hello world" :: "What a lovely day" :: Nil)
@@ -131,7 +136,7 @@ class StreamTcpDocSpec extends AkkaSpec {
       }
 
       val repl = Flow[ByteString]
-        .transform(() => RecipeParseLines.parseLines("\n", maximumLineBytes = 256))
+        .via(Framing.lines("\n", maximumLineBytes = 256, allowTruncation = false))
         .map(text => println("Server: " + text))
         .map(_ => readLine("> "))
         .transform(() ⇒ replParser)