From 221f3c96b5d9479a9eab94fb9df075ec5a1f2253 Mon Sep 17 00:00:00 2001
From: Mike Youngstrom <youngm@gmail.com>
Date: Wed, 21 Dec 2016 17:50:56 -0700
Subject: [PATCH] Skip structured data if it exists.

---
 src/main/java/netty/syslog/DecoderUtil.java   | 25 +++++++++++++++++--
 .../java/netty/syslog/MessageDecoder.java     |  6 +++--
 .../java/netty/syslog/MessageDecoderTest.java | 19 ++++++++++++++
 3 files changed, 46 insertions(+), 4 deletions(-)

diff --git a/src/main/java/netty/syslog/DecoderUtil.java b/src/main/java/netty/syslog/DecoderUtil.java
index e3b5c98..0b2eec1 100644
--- a/src/main/java/netty/syslog/DecoderUtil.java
+++ b/src/main/java/netty/syslog/DecoderUtil.java
@@ -34,11 +34,32 @@ static byte peek(ByteBuf buffer) {
 	}
 
 	static void expect(ByteBuf buffer, char c) {
-		if (buffer.readByte() != c) {
-			throw new DecoderException("Expected " + c + " at index " + buffer.readerIndex());
+		byte readByte = buffer.readByte();
+		if (readByte != c) {
+			throw new DecoderException("Expected " + c + " at index " + buffer.readerIndex() + " got "+ (char)readByte);
 		}
 	}
 
+	static void skipStructuredData(ByteBuf buffer, boolean checkNull) {
+		if (checkNull && peek(buffer) == '-') {
+			buffer.readByte();
+			return;
+		}
+		expect(buffer, '[');
+		int length = -1;
+		for (int i = buffer.readerIndex(); i < buffer.capacity(); i++) {
+			if (buffer.getByte(i) == ' ' && buffer.getByte(i-1) == ']') {
+				length = i - buffer.readerIndex();
+				break;
+			}
+		}
+		if (length < 0) {
+			length = buffer.readableBytes();
+		}
+		buffer.skipBytes(length);
+		return;
+	}
+
 	static String readStringToSpace(ByteBuf buffer, boolean checkNull) {
 		if (checkNull && peek(buffer) == '-') {
 			buffer.readByte();
diff --git a/src/main/java/netty/syslog/MessageDecoder.java b/src/main/java/netty/syslog/MessageDecoder.java
index bb70301..4716b11 100644
--- a/src/main/java/netty/syslog/MessageDecoder.java
+++ b/src/main/java/netty/syslog/MessageDecoder.java
@@ -20,6 +20,7 @@
 import io.netty.channel.ChannelHandlerContext;
 import io.netty.handler.codec.ByteToMessageDecoder;
 import io.netty.handler.codec.DecoderException;
+import io.netty.util.CharsetUtil;
 
 import java.time.ZonedDateTime;
 import java.util.List;
@@ -28,6 +29,7 @@
 import static netty.syslog.DecoderUtil.peek;
 import static netty.syslog.DecoderUtil.readDigit;
 import static netty.syslog.DecoderUtil.readStringToSpace;
+import static netty.syslog.DecoderUtil.skipStructuredData;
 
 public class MessageDecoder extends ByteToMessageDecoder {
 
@@ -85,8 +87,8 @@ protected void decode(ChannelHandlerContext context, ByteBuf buffer, List<Object
 		messageBuilder.messageId(readStringToSpace(buffer, true));
 		expect(buffer, ' ');
 
-		// TODO Decode structured data
-		expect(buffer, '-');
+		// TODO Decode structured data discard for now
+		skipStructuredData(buffer, true);
 		expect(buffer, ' ');
 
 		final int length = buffer.readableBytes();
diff --git a/src/test/java/netty/syslog/MessageDecoderTest.java b/src/test/java/netty/syslog/MessageDecoderTest.java
index 6e51b36..8ebb1fb 100644
--- a/src/test/java/netty/syslog/MessageDecoderTest.java
+++ b/src/test/java/netty/syslog/MessageDecoderTest.java
@@ -33,4 +33,23 @@ public void decode() throws Exception {
 		assertEquals(message.content().toString(StandardCharsets.UTF_8), "SHLVL : 1");
 	}
 
+	@Test
+	public void decodeStructuredData() throws Exception {
+		final MessageDecoder decoder = new MessageDecoder();
+		final List<Object> messageList = new ArrayList<>();
+
+		decoder.decode(null, Unpooled.wrappedBuffer("<14>1 2014-03-20T20:14:14+00:00 loggregator 20d38e29-85bb-4833-81c8-99ba7d0c1b09 [App/0] - [joe=fred dude=garbage][bob=joe] SHLVL : 1".getBytes()), messageList);
+		assertEquals(messageList.size(), 1);
+		final Message message = ((Message) messageList.remove(0));
+		assertEquals(message.getFacility(), Message.Facility.USER_LEVEL);
+		assertEquals(message.getSeverity(), Message.Severity.INFORMATION);
+		assertEquals(message.getTimestamp(), ZonedDateTime.parse("2014-03-20T20:14:14Z"));
+		assertEquals(message.getHostname(), "loggregator");
+		assertEquals(message.getApplicationName(), "20d38e29-85bb-4833-81c8-99ba7d0c1b09");
+		assertEquals(message.getProcessId(), "[App/0]");
+		assertNull(message.getMessageId());
+		assertEquals(message.getStructuredData().size(), 0);
+		assertEquals(message.content().toString(StandardCharsets.UTF_8), "SHLVL : 1");
+	}
+
 }