add preprocessor for RST docs, see #2461 and #2431

The idea is to filter the sources, replacing @<var>@ occurrences with
the mapping for <var> (which is currently hard-coded). @@ -> @. In order
to make this work, I had to move the doc sources one directory down
(into akka-docs/rst) so that the filtered result could be in a sibling
directory so that relative links (to _sphinx plugins or real code) would
continue to work.

While I was at it I also changed it so that WARNINGs and ERRORs are not
swallowed into the debug dump anymore but printed at [warn] level
(minimum).

One piece of fallout is that the (online) html build is now run after
the normal one, not in parallel.

akka-docs/rst/java/code/docs/zeromq/ZeromqDocTest.scala

@@ -0,0 +1,8 @@
+/**
+ * Copyright (C) 2009-2012 Typesafe Inc. <http://www.typesafe.com>
+ */
+package docs.zeromq
+
+import org.scalatest.junit.JUnitSuite
+
+class ZeromqDocTest extends ZeromqDocTestBase with JUnitSuite

akka-docs/rst/java/code/docs/zeromq/ZeromqDocTestBase.java

@@ -0,0 +1,283 @@
+/**
+ * Copyright (C) 2009-2012 Typesafe Inc. <http://www.typesafe.com>
+ */
+package docs.zeromq;
+
+//#pub-socket
+import akka.zeromq.Bind;
+import akka.zeromq.ZeroMQExtension;
+
+//#pub-socket
+//#sub-socket
+import akka.zeromq.Connect;
+import akka.zeromq.Listener;
+import akka.zeromq.Subscribe;
+
+//#sub-socket
+//#unsub-topic-socket
+import akka.zeromq.Unsubscribe;
+
+//#unsub-topic-socket
+//#pub-topic
+import akka.zeromq.Frame;
+import akka.zeromq.ZMQMessage;
+
+//#pub-topic
+
+import akka.zeromq.HighWatermark;
+import akka.zeromq.SocketOption;
+import akka.zeromq.ZeroMQVersion;
+
+//#health
+import akka.actor.ActorRef;
+import akka.actor.UntypedActor;
+import akka.actor.Props;
+import akka.event.Logging;
+import akka.event.LoggingAdapter;
+import scala.concurrent.util.Duration;
+import akka.serialization.SerializationExtension;
+import akka.serialization.Serialization;
+import java.io.Serializable;
+import java.lang.management.ManagementFactory;
+//#health
+
+import com.typesafe.config.ConfigFactory;
+
+import java.lang.management.MemoryMXBean;
+import java.lang.management.MemoryUsage;
+import java.lang.management.OperatingSystemMXBean;
+import java.util.Date;
+import java.text.SimpleDateFormat;
+
+import akka.actor.ActorSystem;
+import akka.testkit.AkkaSpec;
+
+import org.junit.After;
+import org.junit.Before;
+import org.junit.Test;
+import org.junit.Assume;
+
+public class ZeromqDocTestBase {
+
+  ActorSystem system;
+
+  @Before
+  public void setUp() {
+    system = ActorSystem.create("ZeromqDocTest",
+        ConfigFactory.parseString("akka.loglevel=INFO").withFallback(AkkaSpec.testConf()));
+  }
+
+  @After
+  public void tearDown() {
+    system.shutdown();
+  }
+
+  @Test
+  public void demonstrateCreateSocket() {
+    Assume.assumeTrue(checkZeroMQInstallation());
+
+    //#pub-socket
+    ActorRef pubSocket = ZeroMQExtension.get(system).newPubSocket(new Bind("tcp://127.0.0.1:1233"));
+    //#pub-socket
+
+    //#sub-socket
+    ActorRef listener = system.actorOf(new Props(ListenerActor.class));
+    ActorRef subSocket = ZeroMQExtension.get(system).newSubSocket(new Connect("tcp://127.0.0.1:1233"),
+        new Listener(listener), Subscribe.all());
+    //#sub-socket
+
+    //#sub-topic-socket
+    ActorRef subTopicSocket = ZeroMQExtension.get(system).newSubSocket(new Connect("tcp://127.0.0.1:1233"),
+        new Listener(listener), new Subscribe("foo.bar"));
+    //#sub-topic-socket
+
+    //#unsub-topic-socket
+    subTopicSocket.tell(new Unsubscribe("foo.bar"), null);
+    //#unsub-topic-socket
+
+    byte[] payload = new byte[0];
+    //#pub-topic
+    pubSocket.tell(new ZMQMessage(new Frame("foo.bar"), new Frame(payload)), null);
+    //#pub-topic
+
+    //#high-watermark
+    ActorRef highWatermarkSocket = ZeroMQExtension.get(system).newRouterSocket(
+        new SocketOption[] { new Listener(listener), new Bind("tcp://127.0.0.1:1233"), new HighWatermark(50000) });
+    //#high-watermark
+  }
+
+  @Test
+  public void demonstratePubSub() throws Exception {
+    Assume.assumeTrue(checkZeroMQInstallation());
+
+    //#health2
+
+    system.actorOf(new Props(HealthProbe.class), "health");
+    //#health2
+
+    //#logger2
+
+    system.actorOf(new Props(Logger.class), "logger");
+    //#logger2
+
+    //#alerter2
+
+    system.actorOf(new Props(HeapAlerter.class), "alerter");
+    //#alerter2
+
+    // Let it run for a while to see some output.
+    // Don't do like this in real tests, this is only doc demonstration.
+    Thread.sleep(3000L);
+  }
+
+  private boolean checkZeroMQInstallation() {
+    try {
+      ZeroMQVersion v = ZeroMQExtension.get(system).version();
+      return (v.major() == 2 && v.minor() == 1);
+    } catch (LinkageError e) {
+      return false;
+    }
+  }
+
+  //#listener-actor
+  public static class ListenerActor extends UntypedActor {
+    public void onReceive(Object message) throws Exception {
+      //...
+    }
+  }
+
+  //#listener-actor
+
+  //#health
+
+  public static final Object TICK = "TICK";
+
+  public static class Heap implements Serializable {
+    public final long timestamp;
+    public final long used;
+    public final long max;
+
+    public Heap(long timestamp, long used, long max) {
+      this.timestamp = timestamp;
+      this.used = used;
+      this.max = max;
+    }
+  }
+
+  public static class Load implements Serializable {
+    public final long timestamp;
+    public final double loadAverage;
+
+    public Load(long timestamp, double loadAverage) {
+      this.timestamp = timestamp;
+      this.loadAverage = loadAverage;
+    }
+  }
+
+  public static class HealthProbe extends UntypedActor {
+
+    ActorRef pubSocket = ZeroMQExtension.get(getContext().system()).newPubSocket(new Bind("tcp://127.0.0.1:1237"));
+    MemoryMXBean memory = ManagementFactory.getMemoryMXBean();
+    OperatingSystemMXBean os = ManagementFactory.getOperatingSystemMXBean();
+    Serialization ser = SerializationExtension.get(getContext().system());
+
+    @Override
+    public void preStart() {
+      getContext().system().scheduler()
+          .schedule(Duration.create(1, "second"), Duration.create(1, "second"), getSelf(), TICK, getContext().dispatcher());
+    }
+
+    @Override
+    public void postRestart(Throwable reason) {
+      // don't call preStart, only schedule once
+    }
+
+    @Override
+    public void onReceive(Object message) {
+      if (message.equals(TICK)) {
+        MemoryUsage currentHeap = memory.getHeapMemoryUsage();
+        long timestamp = System.currentTimeMillis();
+
+        // use akka SerializationExtension to convert to bytes
+        byte[] heapPayload = ser.serializerFor(Heap.class).toBinary(
+            new Heap(timestamp, currentHeap.getUsed(), currentHeap.getMax()));
+        // the first frame is the topic, second is the message
+        pubSocket.tell(new ZMQMessage(new Frame("health.heap"), new Frame(heapPayload)), getSelf());
+
+        // use akka SerializationExtension to convert to bytes
+        byte[] loadPayload = ser.serializerFor(Load.class).toBinary(new Load(timestamp, os.getSystemLoadAverage()));
+        // the first frame is the topic, second is the message
+        pubSocket.tell(new ZMQMessage(new Frame("health.load"), new Frame(loadPayload)), getSelf());
+      } else {
+        unhandled(message);
+      }
+    }
+
+  }
+
+  //#health
+
+  //#logger
+  public static class Logger extends UntypedActor {
+
+    ActorRef subSocket = ZeroMQExtension.get(getContext().system()).newSubSocket(new Connect("tcp://127.0.0.1:1237"),
+        new Listener(getSelf()), new Subscribe("health"));
+    Serialization ser = SerializationExtension.get(getContext().system());
+    SimpleDateFormat timestampFormat = new SimpleDateFormat("HH:mm:ss.SSS");
+    LoggingAdapter log = Logging.getLogger(getContext().system(), this);
+
+    @Override
+    public void onReceive(Object message) {
+      if (message instanceof ZMQMessage) {
+        ZMQMessage m = (ZMQMessage) message;
+        // the first frame is the topic, second is the message
+        if (m.firstFrameAsString().equals("health.heap")) {
+          Heap heap = (Heap) ser.serializerFor(Heap.class).fromBinary(m.payload(1));
+          log.info("Used heap {} bytes, at {}", heap.used, timestampFormat.format(new Date(heap.timestamp)));
+        } else if (m.firstFrameAsString().equals("health.load")) {
+          Load load = (Load) ser.serializerFor(Load.class).fromBinary(m.payload(1));
+          log.info("Load average {}, at {}", load.loadAverage, timestampFormat.format(new Date(load.timestamp)));
+        }
+      } else {
+        unhandled(message);
+      }
+    }
+
+  }
+
+  //#logger
+
+  //#alerter
+  public static class HeapAlerter extends UntypedActor {
+
+    ActorRef subSocket = ZeroMQExtension.get(getContext().system()).newSubSocket(new Connect("tcp://127.0.0.1:1237"),
+        new Listener(getSelf()), new Subscribe("health.heap"));
+    Serialization ser = SerializationExtension.get(getContext().system());
+    LoggingAdapter log = Logging.getLogger(getContext().system(), this);
+    int count = 0;
+
+    @Override
+    public void onReceive(Object message) {
+      if (message instanceof ZMQMessage) {
+        ZMQMessage m = (ZMQMessage) message;
+        // the first frame is the topic, second is the message
+        if (m.firstFrameAsString().equals("health.heap")) {
+          Heap heap = (Heap) ser.serializerFor(Heap.class).fromBinary(m.payload(1));
+          if (((double) heap.used / heap.max) > 0.9) {
+            count += 1;
+          } else {
+            count = 0;
+          }
+          if (count > 10) {
+            log.warning("Need more memory, using {} %", (100.0 * heap.used / heap.max));
+          }
+        }
+      } else {
+        unhandled(message);
+      }
+    }
+
+  }
+  //#alerter
+
+}