codec.mqtt: password and willMessage field types should be byte[]

Motivation:

Update the mqtt-codec based on mqtt spec (3.1.3.5).

Modification:

Changes made to the file MqttConnectPayload.java.
Subsequent changes have been made to files MqttDecoder.java, MqttEncoder.java, MqttMessageBuilders.java.
Test cases have been updated.
Result:

Fixes #6750 .

codec-mqtt/src/main/java/io/netty/handler/codec/mqtt/MqttConnectPayload.java

@@ -16,6 +16,7 @@
 
 package io.netty.handler.codec.mqtt;
 
+import io.netty.util.CharsetUtil;
 import io.netty.util.internal.StringUtil;
 
 /**
@@ -25,16 +26,34 @@ public final class MqttConnectPayload {
 
     private final String clientIdentifier;
     private final String willTopic;
-    private final String willMessage;
+    private final byte[] willMessage;
     private final String userName;
-    private final String password;
+    private final byte[] password;
 
+    /**
+     * @deprecated use {@link MqttConnectPayload#MqttConnectPayload(String, String, byte[], String, byte[])} instead
+     */
+    @Deprecated
     public MqttConnectPayload(
             String clientIdentifier,
             String willTopic,
             String willMessage,
             String userName,
             String password) {
+        this(
+          clientIdentifier,
+          willTopic,
+          willMessage.getBytes(CharsetUtil.UTF_8),
+          userName,
+          password.getBytes(CharsetUtil.UTF_8));
+    }
+
+    public MqttConnectPayload(
+            String clientIdentifier,
+            String willTopic,
+            byte[] willMessage,
+            String userName,
+            byte[] password) {
         this.clientIdentifier = clientIdentifier;
         this.willTopic = willTopic;
         this.willMessage = willMessage;
@@ -50,7 +69,15 @@ public final class MqttConnectPayload {
         return willTopic;
     }
 
+    /**
+     * @deprecated use {@link MqttConnectPayload#willMessageInBytes()} instead
+     */
+    @Deprecated
     public String willMessage() {
+        return new String(willMessage, CharsetUtil.UTF_8);
+    }
+
+    public byte[] willMessageInBytes() {
         return willMessage;
     }
 
@@ -58,7 +85,15 @@ public final class MqttConnectPayload {
         return userName;
     }
 
+    /**
+     * @deprecated use {@link MqttConnectPayload#passwordInBytes()} instead
+     */
+    @Deprecated
     public String password() {
+        return new String(password, CharsetUtil.UTF_8);
+    }
+
+    public byte[] passwordInBytes() {
         return password;
     }
 

codec-mqtt/src/main/java/io/netty/handler/codec/mqtt/MqttDecoder.java

@@ -339,21 +339,21 @@ public final class MqttDecoder extends ReplayingDecoder<DecoderState> {
         int numberOfBytesConsumed = decodedClientId.numberOfBytesConsumed;
 
         Result<String> decodedWillTopic = null;
-        Result<String> decodedWillMessage = null;
+        Result<byte[]> decodedWillMessage = null;
         if (mqttConnectVariableHeader.isWillFlag()) {
             decodedWillTopic = decodeString(buffer, 0, 32767);
             numberOfBytesConsumed += decodedWillTopic.numberOfBytesConsumed;
-            decodedWillMessage = decodeAsciiString(buffer);
+            decodedWillMessage = decodeByteArray(buffer);
             numberOfBytesConsumed += decodedWillMessage.numberOfBytesConsumed;
         }
         Result<String> decodedUserName = null;
-        Result<String> decodedPassword = null;
+        Result<byte[]> decodedPassword = null;
         if (mqttConnectVariableHeader.hasUserName()) {
             decodedUserName = decodeString(buffer);
             numberOfBytesConsumed += decodedUserName.numberOfBytesConsumed;
         }
         if (mqttConnectVariableHeader.hasPassword()) {
-            decodedPassword = decodeString(buffer);
+            decodedPassword = decodeByteArray(buffer);
             numberOfBytesConsumed += decodedPassword.numberOfBytesConsumed;
         }
 
@@ -419,17 +419,6 @@ public final class MqttDecoder extends ReplayingDecoder<DecoderState> {
         return decodeString(buffer, 0, Integer.MAX_VALUE);
     }
 
-    private static Result<String> decodeAsciiString(ByteBuf buffer) {
-        Result<String> result = decodeString(buffer, 0, Integer.MAX_VALUE);
-        final String s = result.value;
-        for (int i = 0; i < s.length(); i++) {
-            if (s.charAt(i) > 127) {
-                return new Result<String>(null, result.numberOfBytesConsumed);
-            }
-        }
-        return new Result<String>(s, result.numberOfBytesConsumed);
-    }
-
     private static Result<String> decodeString(ByteBuf buffer, int minBytes, int maxBytes) {
         final Result<Integer> decodedSize = decodeMsbLsb(buffer);
         int size = decodedSize.value;
@@ -445,6 +434,14 @@ public final class MqttDecoder extends ReplayingDecoder<DecoderState> {
         return new Result<String>(s, numberOfBytesConsumed);
     }
 
+    private static Result<byte[]> decodeByteArray(ByteBuf buffer) {
+        final Result<Integer> decodedSize = decodeMsbLsb(buffer);
+        int size = decodedSize.value;
+        byte[] bytes = new byte[size];
+        buffer.readBytes(bytes);
+        return new Result<byte[]>(bytes, decodedSize.numberOfBytesConsumed + size);
+    }
+
     private static Result<Integer> decodeMsbLsb(ByteBuf buffer) {
         return decodeMsbLsb(buffer, 0, 65535);
     }

codec-mqtt/src/main/java/io/netty/handler/codec/mqtt/MqttEncoder.java

@@ -113,8 +113,8 @@ public final class MqttEncoder extends MessageToMessageEncoder<MqttMessage> {
         // Will topic and message
         String willTopic = payload.willTopic();
         byte[] willTopicBytes = willTopic != null ? encodeStringUtf8(willTopic) : EmptyArrays.EMPTY_BYTES;
-        String willMessage = payload.willMessage();
+        byte[] willMessage = payload.willMessageInBytes();
-        byte[] willMessageBytes = willMessage != null ? encodeStringUtf8(willMessage) : EmptyArrays.EMPTY_BYTES;
+        byte[] willMessageBytes = willMessage != null ? willMessage : EmptyArrays.EMPTY_BYTES;
         if (variableHeader.isWillFlag()) {
             payloadBufferSize += 2 + willTopicBytes.length;
             payloadBufferSize += 2 + willMessageBytes.length;
@@ -126,8 +126,8 @@ public final class MqttEncoder extends MessageToMessageEncoder<MqttMessage> {
             payloadBufferSize += 2 + userNameBytes.length;
         }
 
-        String password = payload.password();
+        byte[] password = payload.passwordInBytes();
-        byte[] passwordBytes = password != null ? encodeStringUtf8(password) : EmptyArrays.EMPTY_BYTES;
+        byte[] passwordBytes = password != null ? password : EmptyArrays.EMPTY_BYTES;
         if (variableHeader.hasPassword()) {
             payloadBufferSize += 2 + passwordBytes.length;
         }

codec-mqtt/src/main/java/io/netty/handler/codec/mqtt/MqttMessageBuilders.java

@@ -17,6 +17,7 @@ package io.netty.handler.codec.mqtt;
 
 import io.netty.buffer.ByteBuf;
 import io.netty.buffer.Unpooled;
+import io.netty.util.CharsetUtil;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -77,9 +78,9 @@ public final class MqttMessageBuilders {
         private boolean willRetain;
         private MqttQoS willQos = MqttQoS.AT_MOST_ONCE;
         private String willTopic;
-        private String willMessage;
+        private byte[] willMessage;
         private String username;
-        private String password;
+        private byte[] password;
 
         ConnectBuilder() {
         }
@@ -119,7 +120,16 @@ public final class MqttMessageBuilders {
             return this;
         }
 
+        /**
+         * @deprecated use {@link ConnectBuilder#willMessage(byte[])} instead
+         */
+        @Deprecated
         public ConnectBuilder willMessage(String willMessage) {
+            willMessage(willMessage.getBytes(CharsetUtil.UTF_8));
+            return this;
+        }
+
+        public ConnectBuilder willMessage(byte[] willMessage) {
             this.willMessage = willMessage;
             return this;
         }
@@ -145,7 +155,16 @@ public final class MqttMessageBuilders {
             return this;
         }
 
+        /**
+         * @deprecated use {@link ConnectBuilder#password(byte[])} instead
+         */
+        @Deprecated
         public ConnectBuilder password(String password) {
+            password(password.getBytes(CharsetUtil.UTF_8));
+            return this;
+        }
+
+        public ConnectBuilder password(byte[] password) {
             this.hasPassword = true;
             this.password = password;
             return this;

codec-mqtt/src/test/java/io/netty/handler/codec/mqtt/MqttCodecTest.java

@@ -28,6 +28,7 @@ import org.junit.Test;
 import org.mockito.Mock;
 import org.mockito.MockitoAnnotations;
 
+import java.util.Arrays;
 import java.util.LinkedList;
 import java.util.List;
 
@@ -395,7 +396,13 @@ public class MqttCodecTest {
                 actual.clientIdentifier());
         assertEquals("MqttConnectPayload UserName mismatch ", expected.userName(), actual.userName());
         assertEquals("MqttConnectPayload Password mismatch ", expected.password(), actual.password());
+        assertTrue(
+                "MqttConnectPayload Password bytes mismatch ",
+                Arrays.equals(expected.passwordInBytes(), actual.passwordInBytes()));
         assertEquals("MqttConnectPayload WillMessage mismatch ", expected.willMessage(), actual.willMessage());
+        assertTrue(
+                "MqttConnectPayload WillMessage bytes mismatch ",
+                Arrays.equals(expected.willMessageInBytes(), actual.willMessageInBytes()));
         assertEquals("MqttConnectPayload WillTopic mismatch ", expected.willTopic(), actual.willTopic());
     }