!str #16937 Remove section, in favor of via and separate flow

akka-docs-dev/rst/scala/code/docs/stream/FlowErrorDocSpec.scala

@@ -50,9 +50,11 @@ class FlowErrorDocSpec extends AkkaSpec {
       case _: ArithmeticException => Supervision.Resume
       case _                      => Supervision.Stop
     }
-    val source = Source(0 to 5).section(OperationAttributes.supervisionStrategy(decider)) {
-      _.filter(100 / _ < 50).map(elem => 100 / (5 - elem))
-    }
+    val flow = Flow[Int]
+      .filter(100 / _ < 50).map(elem => 100 / (5 - elem))
+      .withAttributes(OperationAttributes.supervisionStrategy(decider))
+    val source = Source(0 to 5).via(flow)
+
     val result = source.runWith(Sink.fold(0)(_ + _))
     // the elements causing division by zero will be dropped
     // result here will be a Future completed with Success(150)
@@ -68,13 +70,13 @@ class FlowErrorDocSpec extends AkkaSpec {
       case _: IllegalArgumentException => Supervision.Restart
       case _                           => Supervision.Stop
     }
-    val source = Source(List(1, 3, -1, 5, 7)).section(
-      OperationAttributes.supervisionStrategy(decider)) {
-        _.scan(0) { (acc, elem) =>
-          if (elem < 0) throw new IllegalArgumentException("negative not allowed")
-          else acc + elem
-        }
+    val flow = Flow[Int]
+      .scan(0) { (acc, elem) =>
+        if (elem < 0) throw new IllegalArgumentException("negative not allowed")
+        else acc + elem
       }
+      .withAttributes(OperationAttributes.supervisionStrategy(decider))
+    val source = Source(List(1, 3, -1, 5, 7)).via(flow)
     val result = source.grouped(1000).runWith(Sink.head)
     // the negative element cause the scan stage to be restarted,
     // i.e. start from 0 again

akka-docs-dev/rst/scala/code/docs/stream/IntegrationDocSpec.scala

@@ -19,6 +19,7 @@ import scala.concurrent.ExecutionContext
 import akka.stream.ActorFlowMaterializerSettings
 import java.util.concurrent.atomic.AtomicInteger
 import akka.stream.Supervision
+import akka.stream.scaladsl.Flow
 
 object IntegrationDocSpec {
   import TwitterStreamQuickstartDocSpec._
@@ -173,9 +174,9 @@ class IntegrationDocSpec extends AkkaSpec(IntegrationDocSpec.config) {
     import Supervision.resumingDecider
 
     val emailAddresses: Source[String, Unit] =
-      authors.section(supervisionStrategy(resumingDecider)) {
-        _.mapAsync(4, author => addressSystem.lookupEmail(author.handle))
-      }
+      authors.via(
+        Flow[Author].mapAsync(4, author => addressSystem.lookupEmail(author.handle))
+          .withAttributes(supervisionStrategy(resumingDecider)))
     //#email-addresses-mapAsync-supervision
   }
 
@@ -263,15 +264,13 @@ class IntegrationDocSpec extends AkkaSpec(IntegrationDocSpec.config) {
         .collect { case Some(phoneNo) => phoneNo }
 
     //#blocking-map
+    val send = Flow[String]
+      .map { phoneNo =>
+        smsServer.send(TextMessage(to = phoneNo, body = "I like your tweet"))
+      }
+      .withAttributes(OperationAttributes.dispatcher("blocking-dispatcher"))
     val sendTextMessages: RunnableFlow[Unit] =
-      phoneNumbers
-        .section(OperationAttributes.dispatcher("blocking-dispatcher")) {
-          _.map { phoneNo =>
-            smsServer.send(
-              TextMessage(to = phoneNo, body = "I like your tweet"))
-          }
-        }
-        .to(Sink.ignore)
+      phoneNumbers.via(send).to(Sink.ignore)
 
     sendTextMessages.run()
     //#blocking-map

akka-docs-dev/rst/scala/code/docs/stream/StreamBuffersRateSpec.scala

@@ -28,13 +28,9 @@ class StreamBuffersRateSpec extends AkkaSpec {
     //#materializer-buffer
 
     //#section-buffer
-    val flow =
-      Flow[Int]
-        .section(OperationAttributes.inputBuffer(initial = 1, max = 1)) { sectionFlow =>
-          // the buffer size of this map is 1
-          sectionFlow.map(_ * 2)
-        }
-        .map(_ / 2) // the buffer size of this map is the default
+    val section = Flow[Int].map(_ * 2)
+      .withAttributes(OperationAttributes.inputBuffer(initial = 1, max = 1))
+    val flow = section.via(Flow[Int].map(_ / 2)) // the buffer size of this map is the default
     //#section-buffer
   }