Merge "Bug 809: Enhancements to the toaster example"

[controller.git] / opendaylight / netconf / netconf-util / src / main / java / org / opendaylight / controller / netconf / util / handler / NetconfXMLToHelloMessageDecoder.java

diff --git a/opendaylight/netconf/netconf-util/src/main/java/org/opendaylight/controller/netconf/util/handler/NetconfXMLToHelloMessageDecoder.java b/opendaylight/netconf/netconf-util/src/main/java/org/opendaylight/controller/netconf/util/handler/NetconfXMLToHelloMessageDecoder.java
index 248871a7aa3b4b6f3c60efffae0022791dad4624..361d4fcee908018eac90a54844569ced70c22a21 100644 (file)
--- a/opendaylight/netconf/netconf-util/src/main/java/org/opendaylight/controller/netconf/util/handler/NetconfXMLToHelloMessageDecoder.java
+++ b/opendaylight/netconf/netconf-util/src/main/java/org/opendaylight/controller/netconf/util/handler/NetconfXMLToHelloMessageDecoder.java
@@ -7,16 +7,20 @@
  */
 package org.opendaylight.controller.netconf.util.handler;
 
+import com.google.common.base.Preconditions;
+import com.google.common.collect.Lists;
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.ByteBufUtil;
 import io.netty.channel.ChannelHandlerContext;
 import io.netty.handler.codec.ByteToMessageDecoder;
 
 import java.io.ByteArrayInputStream;
+import java.io.IOException;
 import java.nio.ByteBuffer;
 import java.util.Arrays;
 import java.util.List;
 
+import org.opendaylight.controller.netconf.api.NetconfDocumentedException;
 import org.opendaylight.controller.netconf.api.NetconfMessage;
 import org.opendaylight.controller.netconf.util.messages.NetconfHelloMessage;
 import org.opendaylight.controller.netconf.util.messages.NetconfHelloMessageAdditionalHeader;
@@ -28,12 +32,18 @@ import org.w3c.dom.Document;
 import com.google.common.annotations.VisibleForTesting;
 import com.google.common.base.Charsets;
 import com.google.common.collect.ImmutableList;
+import org.xml.sax.SAXException;
 
 /**
  * Customized NetconfXMLToMessageDecoder that reads additional header with
  * session metadata from
  * {@link org.opendaylight.controller.netconf.util.messages.NetconfHelloMessage}
- * . Used by netconf server to retrieve information about session metadata.
+ *
+ *
+ * This handler should be replaced in pipeline by regular message handler as last step of negotiation.
+ * It serves as a message barrier and halts all non-hello netconf messages.
+ * Netconf messages after hello should be processed once the negotiation succeeded.
+ *
  */
 public final class NetconfXMLToHelloMessageDecoder extends ByteToMessageDecoder {
     private static final Logger LOG = LoggerFactory.getLogger(NetconfXMLToHelloMessageDecoder.class);
@@ -46,9 +56,15 @@ public final class NetconfXMLToHelloMessageDecoder extends ByteToMessageDecoder
             new byte[] { '\r', '\n', '[' },
             new byte[] { '\n', '[' });
 
+    // State variables do not have to by synchronized
+    // Netty uses always the same (1) thread per pipeline
+    // We use instance of this per pipeline
+    private List<NetconfMessage> nonHelloMessages = Lists.newArrayList();
+    private boolean helloReceived = false;
+
     @Override
     @VisibleForTesting
-    public void decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out) throws Exception {
+    public void decode(ChannelHandlerContext ctx, ByteBuf in, List<Object> out) throws IOException, SAXException, NetconfDocumentedException {
         if (in.readableBytes() == 0) {
             LOG.debug("No more content in incoming buffer.");
             return;
@@ -76,18 +92,39 @@ public final class NetconfXMLToHelloMessageDecoder extends ByteToMessageDecoder
 
             Document doc = XmlUtil.readXmlToDocument(new ByteArrayInputStream(bytes));
 
-            final NetconfMessage message;
-            if (additionalHeader != null) {
-                message = new NetconfHelloMessage(doc, NetconfHelloMessageAdditionalHeader.fromString(additionalHeader));
+            final NetconfMessage message = getNetconfMessage(additionalHeader, doc);
+            if (message instanceof NetconfHelloMessage) {
+                Preconditions.checkState(helloReceived == false,
+                        "Multiple hello messages received, unexpected hello: %s",
+                        XmlUtil.toString(message.getDocument()));
+                out.add(message);
+                helloReceived = true;
+            // Non hello message, suspend the message and insert into cache
             } else {
-                message = new NetconfHelloMessage(doc);
+                Preconditions.checkState(helloReceived, "Hello message not received, instead received: %s",
+                        XmlUtil.toString(message.getDocument()));
+                LOG.debug("Netconf message received during negotiation, caching {}",
+                        XmlUtil.toString(message.getDocument()));
+                nonHelloMessages.add(message);
             }
-            out.add(message);
         } finally {
             in.discardReadBytes();
         }
     }
 
+    private NetconfMessage getNetconfMessage(final String additionalHeader, final Document doc) throws NetconfDocumentedException {
+        NetconfMessage msg = new NetconfMessage(doc);
+        if(NetconfHelloMessage.isHelloMessage(msg)) {
+            if (additionalHeader != null) {
+                return new NetconfHelloMessage(doc, NetconfHelloMessageAdditionalHeader.fromString(additionalHeader));
+            } else {
+                return new NetconfHelloMessage(doc);
+            }
+        }
+
+        return msg;
+    }
+
     private int getAdditionalHeaderEndIndex(byte[] bytes) {
         for (byte[] possibleEnd : POSSIBLE_ENDS) {
             int idx = findByteSequence(bytes, possibleEnd);
@@ -135,11 +172,13 @@ public final class NetconfXMLToHelloMessageDecoder extends ByteToMessageDecoder
         for (byte[] possibleStart : POSSIBLE_STARTS) {
             int i = 0;
             for (byte b : possibleStart) {
-                if(bytes[i++] != b)
+                if(bytes[i++] != b) {
                     break;
+                }
 
-                if(i == possibleStart.length)
+                if(i == possibleStart.length) {
                     return true;
+                }
             }
         }
 
@@ -150,4 +189,10 @@ public final class NetconfXMLToHelloMessageDecoder extends ByteToMessageDecoder
         return Charsets.UTF_8.decode(ByteBuffer.wrap(bytes)).toString();
     }
 
+    /**
+     * @return Collection of NetconfMessages that were not hello, but were received during negotiation
+     */
+    public Iterable<NetconfMessage> getPostHelloNetconfMessages() {
+        return nonHelloMessages;
+    }
 }