Initial MQTT packet structure. issue 73

src/zutil/net/mqtt/packet/MqttPacketConnect.java

@@ -0,0 +1,71 @@
+package zutil.net.mqtt.packet;
+
+import zutil.parser.binary.BinaryStruct;
+
+/**
+ * This packet is the first message sent from a Client when it
+ * has established a connection to a Server. A Client can only
+ * send the CONNECT Packet once over a Network Connection.
+ *
+ * @see <a href="http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/mqtt-v3.1.1.html">MQTT v3.1.1 Spec</a>
+ */
+public class MqttPacketConnect implements BinaryStruct {
+
+    // Variable header
+
+    @BinaryField(index = 2001, length = 16)
+    private int protocolNameLength = 4;
+    /**
+     * The Protocol Name is a UTF-8 encoded string that represents
+     * the protocol name “MQTT”, capitalized as shown. The string,
+     * its offset and length will not be changed by future versions
+     * of the MQTT specification.
+     */
+    @BinaryField(index = 2002, length = 8*4)
+    public String protocolName = "MQTT";
+
+    /**
+     * The value represents the revision level of the protocol used by
+     * the Client. The value of the Protocol Level field for the version
+     * 3.1.1 of the protocol is 4 (0x04)
+     */
+    @BinaryField(index = 2003, length = 8)
+    public int protocolLevel = 0x04;
+
+
+    /** Indicates that the payload contains a username */
+    @BinaryField(index = 2010, length = 1)
+    public boolean flagUsername;
+    /** Indicates that the payload contains a password */
+    @BinaryField(index = 2011, length = 1)
+    public boolean flagPassword;
+    /** Specifies if the Will Message is to be Retained when it is published. */
+    @BinaryField(index = 2012, length = 1)
+    public boolean flagWillRetain;
+    /** Specifies the QoS level to be used when publishing the Will Message. */
+    @BinaryField(index = 2013, length = 2)
+    public int flagWillQoS;
+    @BinaryField(index = 2014, length = 1)
+    public boolean flagWillFlag;
+    @BinaryField(index = 2015, length = 1)
+    /** This bit specifies the handling of the Session state. */
+    public boolean flagCleanSession;
+    @BinaryField(index = 2016, length = 1)
+    private boolean reserved;
+
+
+    /**
+     * The Keep Alive is a time interval measured in seconds and
+     * it is the maximum time interval that is permitted to elapse
+     * between the point at which the Client finishes transmitting one
+     * Control Packet and the point it starts sending the next.
+     * A Keep Alive value of zero (0) has the effect of turning off
+     * the keep alive mechanism.
+     */
+    @BinaryField(index = 2020, length = 16)
+    public int keepAlive;
+
+
+    // Payload
+
+}

src/zutil/net/mqtt/packet/MqttPacketConnectAck.java

@@ -0,0 +1,29 @@
+package zutil.net.mqtt.packet;
+
+import zutil.parser.binary.BinaryStruct;
+
+/**
+ * The CONNACK Packet is the packet sent by the Server in response to a
+ * CONNECT Packet received from a Client.
+ *
+ * @see <a href="http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/mqtt-v3.1.1.html">MQTT v3.1.1 Spec</a>
+ */
+public class MqttPacketConnectAck implements BinaryStruct{
+    public static final int RETCODE_OK                 = 0;
+    public static final int RETCODE_PROT_VER_ERROR     = 1;
+    public static final int RETCODE_IDENTIFIER_REJECT  = 2;
+    public static final int RETCODE_SERVER_UNAVAILABLE = 3;
+    public static final int RETCODE_BADD_USER_OR_PASS  = 4;
+    public static final int RETCODE_NOT_AUTHORIZED     = 5;
+
+
+    @BinaryField(index = 2000, length = 7)
+    private int flagReserved;
+    /** Indicates that there is a valid Session available */
+    @BinaryField(index = 2001, length = 1)
+    public int flagSessionPresent;
+
+    @BinaryField(index = 2002, length = 8)
+    public int returnCode;
+
+}

src/zutil/net/mqtt/packet/MqttPacketDisconnect.java

@@ -0,0 +1,14 @@
+package zutil.net.mqtt.packet;
+
+import zutil.parser.binary.BinaryStruct;
+
+/**
+ * The DISCONNECT Packet is the final Control Packet sent from the Client to
+ * the Server. It indicates that the Client is disconnecting cleanly.
+ *
+ * @see <a href="http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/mqtt-v3.1.1.html">MQTT v3.1.1 Spec</a>
+ */
+public class MqttPacketDisconnect implements BinaryStruct{
+
+
+}

src/zutil/net/mqtt/packet/MqttPacketHeader.java

@@ -0,0 +1,36 @@
+package zutil.net.mqtt.packet;
+
+import zutil.parser.binary.BinaryStruct;
+
+/**
+ *
+ */
+public class MqttPacketHeader implements BinaryStruct {
+
+    //                      RESERVED                = 0;
+    public static final int PACKET_TYPE_CONNACK     = 2;
+    public static final int PACKET_TYPE_PUBLISH     = 3;
+    public static final int PACKET_TYPE_PUBACK      = 4;
+    public static final int PACKET_TYPE_PUBREC      = 5;
+    public static final int PACKET_TYPE_PUBREL      = 6;
+    public static final int PACKET_TYPE_PUBCOMP     = 7;
+    public static final int PACKET_TYPE_SUBSCRIBE   = 8;
+    public static final int PACKET_TYPE_SUBACK      = 9;
+    public static final int PACKET_TYPE_UNSUBSCRIBE = 10;
+    public static final int PACKET_TYPE_UNSUBACK    = 11;
+    public static final int PACKET_TYPE_PINGREQ     = 12;
+    public static final int PACKET_TYPE_PINGRESP    = 13;
+    public static final int PACKET_TYPE_DISCONNECT  = 14;
+    //                      RESERVED                = 15
+
+
+
+    @BinaryField(index = 1, length = 4)
+    private byte type;
+    @BinaryField(index = 2, length = 4)
+    private byte flags;
+
+    @CustomBinaryField(index = 3, serializer = MqttVariableIntSerializer.class)
+    private int length;
+
+}

src/zutil/net/mqtt/packet/MqttPacketPingReq.java

@@ -0,0 +1,13 @@
+package zutil.net.mqtt.packet;
+
+import zutil.parser.binary.BinaryStruct;
+
+/**
+ * The PINGREQ Packet is used in Keep Alive processing
+ *
+ * @see <a href="http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/mqtt-v3.1.1.html">MQTT v3.1.1 Spec</a>
+ */
+public class MqttPacketPingReq implements BinaryStruct{
+
+
+}

src/zutil/net/mqtt/packet/MqttPacketPingResp.java

@@ -0,0 +1,14 @@
+package zutil.net.mqtt.packet;
+
+import zutil.parser.binary.BinaryStruct;
+
+/**
+ * A PINGRESP Packet is sent by the Server to the Client in response to a
+ * PINGREQ Packet. It indicates that the Server is alive.
+ *
+ * @see <a href="http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/mqtt-v3.1.1.html">MQTT v3.1.1 Spec</a>
+ */
+public class MqttPacketPingResp implements BinaryStruct{
+
+
+}

src/zutil/net/mqtt/packet/MqttPacketPublish.java

@@ -0,0 +1,39 @@
+package zutil.net.mqtt.packet;
+
+import zutil.parser.binary.BinaryStruct;
+
+/**
+ * A PUBLISH Control Packet is sent from a Client to a Server
+ *
+ * @see <a href="http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/mqtt-v3.1.1.html">MQTT v3.1.1 Spec</a>
+ */
+public class MqttPacketPublish implements BinaryStruct{
+
+    // Static Header
+/*
+    @BinaryField(index = 2000, length = 1)
+    private int flagDup;
+    @BinaryField(index = 2001, length = 2)
+    private int flagQoS;
+    @BinaryField(index = 2002, length = 1)
+    private int flagRetain;
+
+    @CustomBinaryField(index = 3, serializer = MqttVariableIntSerializer.class)
+    private int length;
+*/
+
+    // Variable Header
+
+    @BinaryField(index = 2101, length = 16)
+    private int topicNameLength;
+    /** The Topic Name identifies the information channel to which payload data is published. */
+    @VariableLengthBinaryField(index = 2102, lengthField = "topicNameLength")
+    public String topicName;
+
+    @BinaryField(index = 2102, length = 16)
+    public int packetId;
+
+
+    // Optional Payload
+
+}

src/zutil/net/mqtt/packet/MqttPacketPublishAck.java

@@ -0,0 +1,18 @@
+package zutil.net.mqtt.packet;
+
+import zutil.parser.binary.BinaryStruct;
+
+/**
+ * A PUBACK Packet is the response to a PUBLISH Packet with QoS level 1.
+ *
+ * @see <a href="http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/mqtt-v3.1.1.html">MQTT v3.1.1 Spec</a>
+ */
+public class MqttPacketPublishAck implements BinaryStruct{
+
+    // Variable Header
+
+    @BinaryField(index = 2000, length = 16)
+    public int packetId;
+
+
+}

src/zutil/net/mqtt/packet/MqttPacketPublishComp.java

@@ -0,0 +1,20 @@
+package zutil.net.mqtt.packet;
+
+import zutil.parser.binary.BinaryStruct;
+
+/**
+ * Publish complete.
+ * The PUBCOMP Packet is the response to a PUBREL Packet. It is the fourth and
+ * final packet of the QoS 2 protocol exchange.
+ *
+ * @see <a href="http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/mqtt-v3.1.1.html">MQTT v3.1.1 Spec</a>
+ */
+public class MqttPacketPublishComp implements BinaryStruct{
+
+    // Variable Header
+
+    @BinaryField(index = 2000, length = 16)
+    public int packetId;
+
+
+}

src/zutil/net/mqtt/packet/MqttPacketPublishRec.java

@@ -0,0 +1,20 @@
+package zutil.net.mqtt.packet;
+
+import zutil.parser.binary.BinaryStruct;
+
+/**
+ * Publish received.
+ * A PUBREC Packet is the response to a PUBLISH Packet with QoS 2. It is the
+ * second packet of the QoS 2 protocol exchange.
+ *
+ * @see <a href="http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/mqtt-v3.1.1.html">MQTT v3.1.1 Spec</a>
+ */
+public class MqttPacketPublishRec implements BinaryStruct{
+
+    // Variable Header
+
+    @BinaryField(index = 2000, length = 16)
+    public int packetId;
+
+
+}

src/zutil/net/mqtt/packet/MqttPacketPublishRel.java

@@ -0,0 +1,20 @@
+package zutil.net.mqtt.packet;
+
+import zutil.parser.binary.BinaryStruct;
+
+/**
+ * Publish release.
+ * A PUBREL Packet is the response to a PUBREC Packet. It is the third packet
+ * of the QoS 2 protocol exchange.
+ *
+ * @see <a href="http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/mqtt-v3.1.1.html">MQTT v3.1.1 Spec</a>
+ */
+public class MqttPacketPublishRel implements BinaryStruct{
+
+    // Variable Header
+
+    @BinaryField(index = 2000, length = 16)
+    public int packetId;
+
+
+}

src/zutil/net/mqtt/packet/MqttPacketSubscribe.java

@@ -0,0 +1,39 @@
+package zutil.net.mqtt.packet;
+
+import zutil.parser.binary.BinaryStruct;
+
+import java.util.List;
+
+/**
+ * The SUBSCRIBE Packet is sent from the Client to the Server to create one or more Subscriptions.
+ *
+ * @see <a href="http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/mqtt-v3.1.1.html">MQTT v3.1.1 Spec</a>
+ */
+public class MqttPacketSubscribe implements BinaryStruct{
+
+    // Variable Header
+
+    @BinaryField(index = 2000, length = 16)
+    public int packetId;
+
+    // Payload
+
+    public List<MqttSubscribePayload> payload;
+
+
+
+
+    public static class MqttSubscribePayload implements BinaryStruct{
+
+        @BinaryField(index = 3001, length = 16)
+        private int topicFilterLength;
+        /** A filter indicating the Topic to which the Client wants to subscribe to*/
+        @VariableLengthBinaryField(index = 3002, lengthField = "topicFilterLength")
+        public String topicFilter;
+
+        @BinaryField(index = 3003, length = 6)
+        private int reserved;
+        @BinaryField(index = 3004, length = 2)
+        private int qos;
+    }
+}

src/zutil/net/mqtt/packet/MqttPacketSubscribeAck.java

@@ -0,0 +1,36 @@
+package zutil.net.mqtt.packet;
+
+import zutil.parser.binary.BinaryStruct;
+
+import java.util.List;
+
+/**
+ * A SUBACK Packet is sent by the Server to the Client to confirm receipt
+ * and processing of a SUBSCRIBE Packet.
+ *
+ * @see <a href="http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/mqtt-v3.1.1.html">MQTT v3.1.1 Spec</a>
+ */
+public class MqttPacketSubscribeAck implements BinaryStruct{
+
+    // Variable Header
+
+    @BinaryField(index = 2000, length = 16)
+    public int packetId;
+
+    // Payload
+
+    public List<MqttSubscribeAckPayload> payload;
+
+
+
+
+    public static class MqttSubscribeAckPayload implements BinaryStruct{
+        public static final int RETCODE_SUCESS_MAX_QOS_0 = 0;
+        public static final int RETCODE_SUCESS_MAX_QOS_1 = 1;
+        public static final int RETCODE_SUCESS_MAX_QOS_2 = 2;
+        public static final int RETCODE_FAILURE          = 0x80;
+
+        @BinaryField(index = 3001, length = 8)
+        public int returnCode;
+    }
+}

src/zutil/net/mqtt/packet/MqttPacketUnsubscribe.java

@@ -0,0 +1,35 @@
+package zutil.net.mqtt.packet;
+
+import zutil.parser.binary.BinaryStruct;
+
+import java.util.List;
+
+/**
+ * An UNSUBSCRIBE Packet is sent by the Client to the Server, to unsubscribe from topics.
+ *
+ * @see <a href="http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/mqtt-v3.1.1.html">MQTT v3.1.1 Spec</a>
+ */
+public class MqttPacketUnsubscribe implements BinaryStruct{
+
+    // Variable Header
+
+    @BinaryField(index = 2000, length = 16)
+    public int packetId;
+
+    // Payload
+
+    public List<MqttUnsubscribePayload> payload;
+
+
+
+
+    public static class MqttUnsubscribePayload implements BinaryStruct{
+
+        @BinaryField(index = 3001, length = 16)
+        private int topicFilterLength;
+        /** A filter indicating the Topic to which the Client wants to subscribe to*/
+        @VariableLengthBinaryField(index = 3002, lengthField = "topicFilterLength")
+        public String topicFilter;
+
+    }
+}

src/zutil/net/mqtt/packet/MqttPacketUnsubscribeAck.java

@@ -0,0 +1,20 @@
+package zutil.net.mqtt.packet;
+
+import zutil.parser.binary.BinaryStruct;
+
+import java.util.List;
+
+/**
+ * The UNSUBACK Packet is sent by the Server to the Client to confirm receipt
+ * of an UNSUBSCRIBE Packet.
+ *
+ * @see <a href="http://docs.oasis-open.org/mqtt/mqtt/v3.1.1/mqtt-v3.1.1.html">MQTT v3.1.1 Spec</a>
+ */
+public class MqttPacketUnsubscribeAck implements BinaryStruct{
+
+    // Variable Header
+
+    @BinaryField(index = 2000, length = 16)
+    public int packetId;
+
+}

src/zutil/net/mqtt/packet/MqttVariableIntSerializer.java

@@ -0,0 +1,43 @@
+package zutil.net.mqtt.packet;
+
+import zutil.parser.binary.BinaryFieldData;
+import zutil.parser.binary.BinaryFieldSerializer;
+
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.OutputStream;
+
+/**
+ * Code from MQTT specification
+ */
+public class MqttVariableIntSerializer implements BinaryFieldSerializer<Integer>{
+
+    @Override
+    public Integer read(InputStream in, BinaryFieldData field) throws IOException {
+        int multiplier = 1;
+        int value = 0;
+        int encodedByte;
+        do {
+            encodedByte = in.read();
+            value += (encodedByte & 127) * multiplier;
+            if (multiplier > 128 * 128 * 128)
+                throw new IOException("Malformed Remaining Length");
+            multiplier *= 128;
+        } while ((encodedByte & 128) != 0);
+        return value;
+    }
+
+    @Override
+    public void write(OutputStream out, Integer obj, BinaryFieldData field) throws IOException {
+        int x = obj;
+        int encodedByte;
+        do {
+            encodedByte = x % 128;
+            x = x / 128;
+            // if there are more data to encode, set the top bit of this byte
+            if (x > 0)
+                encodedByte = encodedByte & 128;
+            out.write(encodedByte);
+        } while ( x > 0 );
+    }
+}

src/zutil/parser/binary/BinaryFieldData.java

@@ -101,7 +101,7 @@ public class BinaryFieldData {
             else if (field.getType() == String.class)
                 field.set(obj, new String(ByteUtil.getReverseByteOrder(data), StandardCharsets.ISO_8859_1));
             else
-                throw new UnsupportedOperationException("Unsupported BinaryStruct field class: "+ field.getClass());
+                throw new UnsupportedOperationException("Unsupported BinaryStruct field class: "+ field.getType());
         } catch (IllegalAccessException e){
             e.printStackTrace();
         }

src/zutil/parser/binary/BinaryStruct.java

@@ -30,6 +30,9 @@ import java.lang.annotation.RetentionPolicy;
 import java.lang.annotation.Target;
 
 /**
+ * A interface that indicate that the implementing class can
+ * be serialized into a linear binary stream.
+ *
  * Created by Ziver on 2016-01-28.
  */
 public interface BinaryStruct {
@@ -47,7 +50,9 @@ public interface BinaryStruct {
     }
 
     /**
-     * Can be used for fields that are of variable length.
+     * Can be used for fields that are of variable length. This interface
+     * is only applicable for reading from a stream.
+     * TODO: Length must be manually set when writing.
      */
     @Retention(RetentionPolicy.RUNTIME)
     @Target(ElementType.FIELD)
@@ -56,8 +61,8 @@ public interface BinaryStruct {
         int index();
         /** The name of the field that will contain the length of the data to read. */
         String lengthField();
-        /** Defines the multiplier used on the lengthField to convert to length in bits which is used internally.
-         * Default value is 8. */
+        /** Defines the multiplier used on the lengthField parameter to convert the length in bits to
+         *  a user defined value. Default value is 8 (which converts length to nr of bytes). */
         int multiplier() default 8;
     }
 

test/zutil/net/mqtt/packet/MqttPacketConnectTest.java

@@ -0,0 +1,65 @@
+package zutil.net.mqtt.packet;
+
+import org.junit.Test;
+import zutil.converter.Converter;
+import zutil.net.mqtt.packet.MqttPacketConnect;
+import zutil.parser.binary.BinaryStructInputStream;
+import zutil.parser.binary.BinaryStructOutputStream;
+
+import java.io.IOException;
+
+import static org.junit.Assert.*;
+
+
+public class MqttPacketConnectTest {
+
+    char[] data = new char[]{
+            0b0000_0000, // length
+            0b0000_0100, // length
+            0b0100_1101, // 'M'
+            0b0101_0001, // 'Q'
+            0b0101_0100, // 'T'
+            0b0101_0100, // 'T'
+
+            0b0000_0100, // Prot. Level
+
+            0b1100_1110, // Flags
+
+            0b0000_0000, // Keep alive
+            0b0000_1010, // Keep alive
+    };
+
+
+    @Test
+    public void decode(){
+        MqttPacketConnect obj = new MqttPacketConnect();
+        BinaryStructInputStream.read(obj, Converter.toBytes(data));
+
+        assertEquals("MQTT", obj.protocolName);
+        assertEquals(4, obj.protocolLevel);
+        assertEquals(10, obj.keepAlive);
+
+        assertTrue(obj.flagUsername);
+        assertTrue(obj.flagPassword);
+        assertFalse(obj.flagWillRetain);
+        assertEquals(1, obj.flagWillQoS);
+        assertTrue(obj.flagWillFlag);
+        assertTrue(obj.flagCleanSession);
+    }
+
+    @Test
+    public void encode() throws IOException {
+        MqttPacketConnect obj = new MqttPacketConnect();
+        obj.keepAlive = 10;
+
+        obj.flagUsername = true;
+        obj.flagPassword = true;
+        obj.flagWillRetain = false;
+        obj.flagWillQoS = 1;
+        obj.flagWillFlag = true;
+        obj.flagCleanSession = true;
+
+        assertArrayEquals(Converter.toBytes(data),
+                BinaryStructOutputStream.serialize(obj));
+    }
+}