feat: support headers for message

src/main/java/io/numaproj/numaflow/mapper/Datum.java

@@ -2,6 +2,7 @@
 
 
 import java.time.Instant;
+import java.util.Map;
 
 /**
  * Datum contains methods to get the payload information.
@@ -28,4 +29,11 @@ public interface Datum {
      * @return returns the watermark
      */
     public Instant getWatermark();
+
+    /**
+     * method to get the headers information of the payload
+     *
+     * @return returns the headers in the form of key value pair
+     */
+    public Map<String, String> getHeaders();
 }

src/main/java/io/numaproj/numaflow/mapper/HandlerDatum.java

@@ -4,13 +4,15 @@
 import lombok.AllArgsConstructor;
 
 import java.time.Instant;
+import java.util.Map;
 
 @AllArgsConstructor
 class HandlerDatum implements Datum {
 
     private byte[] value;
     private Instant watermark;
     private Instant eventTime;
+    private Map<String, String> headers;
 
 
     @Override
@@ -28,4 +30,9 @@ public Instant getEventTime() {
         return this.eventTime;
     }
 
+    @Override
+    public Map<String, String> getHeaders() {
+        return this.headers;
+    }
+
 }

src/main/java/io/numaproj/numaflow/mapper/Service.java

@@ -42,7 +42,8 @@ public void mapFn(
                         request.getWatermark().getNanos()),
                 Instant.ofEpochSecond(
                         request.getEventTime().getSeconds(),
-                        request.getEventTime().getNanos())
+                        request.getEventTime().getNanos()),
+                request.getHeadersMap()
         );
 
         // process request

src/main/java/io/numaproj/numaflow/mapstreamer/Datum.java

@@ -1,6 +1,7 @@
 package io.numaproj.numaflow.mapstreamer;
 
 import java.time.Instant;
+import java.util.Map;
 
 /**
  * Datum contains methods to get the payload information.
@@ -27,4 +28,11 @@ public interface Datum {
      * @return returns the watermark
      */
     public Instant getWatermark();
+
+    /**
+     * method to get the headers information of the payload
+     *
+     * @return returns the headers in the form of key value pair
+     */
+    public Map<String, String> getHeaders();
 }

src/main/java/io/numaproj/numaflow/mapstreamer/HandlerDatum.java

@@ -4,13 +4,15 @@
 import lombok.AllArgsConstructor;
 
 import java.time.Instant;
+import java.util.Map;
 
 @AllArgsConstructor
 class HandlerDatum implements Datum {
 
     private byte[] value;
     private Instant watermark;
     private Instant eventTime;
+    private Map<String, String> headers;
 
 
     @Override
@@ -28,4 +30,9 @@ public Instant getEventTime() {
         return this.eventTime;
     }
 
+    @Override
+    public Map<String, String> getHeaders() {
+        return this.headers;
+    }
+
 }

src/main/java/io/numaproj/numaflow/mapstreamer/Service.java

@@ -40,7 +40,8 @@ public void mapStreamFn(
                         request.getWatermark().getNanos()),
                 Instant.ofEpochSecond(
                         request.getEventTime().getSeconds(),
-                        request.getEventTime().getNanos())
+                        request.getEventTime().getNanos()),
+                request.getHeadersMap()
         );
 
         // process Datum

src/main/java/io/numaproj/numaflow/reducer/Datum.java

@@ -1,6 +1,7 @@
 package io.numaproj.numaflow.reducer;
 
 import java.time.Instant;
+import java.util.Map;
 
 /**
  * Datum contains methods to get the payload information.
@@ -27,4 +28,11 @@ public interface Datum {
      * @return returns the watermark
      */
     public Instant getWatermark();
+
+    /**
+     * method to get the headers information of the payload
+     *
+     * @return returns the headers in the form of key value pair
+     */
+    public Map<String, String> getHeaders();
 }

src/main/java/io/numaproj/numaflow/reducer/HandlerDatum.java

@@ -4,12 +4,14 @@
 import lombok.AllArgsConstructor;
 
 import java.time.Instant;
+import java.util.Map;
 
 @AllArgsConstructor
 class HandlerDatum implements Datum {
     private byte[] value;
     private Instant watermark;
     private Instant eventTime;
+    private Map<String, String> headers;
 
     @Override
     public Instant getWatermark() {
@@ -25,4 +27,9 @@ public byte[] getValue() {
     public Instant getEventTime() {
         return this.eventTime;
     }
+
+    @Override
+    public Map<String, String> getHeaders() {
+        return this.headers;
+    }
 }

src/main/java/io/numaproj/numaflow/reducer/ReduceSupervisorActor.java

@@ -135,7 +135,8 @@ private HandlerDatum constructHandlerDatum(ReduceOuterClass.ReduceRequest.Payloa
                         payload.getWatermark().getNanos()),
                 Instant.ofEpochSecond(
                         payload.getEventTime().getSeconds(),
-                        payload.getEventTime().getNanos())
+                        payload.getEventTime().getNanos()),
+                payload.getHeadersMap()
         );
     }
 

src/main/java/io/numaproj/numaflow/reducestreamer/HandlerDatum.java

@@ -4,12 +4,14 @@
 import lombok.AllArgsConstructor;
 
 import java.time.Instant;
+import java.util.Map;
 
 @AllArgsConstructor
 class HandlerDatum implements Datum {
     private byte[] value;
     private Instant watermark;
     private Instant eventTime;
+    private Map<String, String> headers;
 
     @Override
     public Instant getWatermark() {
@@ -25,4 +27,9 @@ public byte[] getValue() {
     public Instant getEventTime() {
         return this.eventTime;
     }
+
+    @Override
+    public Map<String, String> getHeaders() {
+        return this.headers;
+    }
 }

src/main/java/io/numaproj/numaflow/reducestreamer/SupervisorActor.java

@@ -136,7 +136,8 @@ private HandlerDatum constructHandlerDatum(ReduceOuterClass.ReduceRequest.Payloa
                         payload.getWatermark().getNanos()),
                 Instant.ofEpochSecond(
                         payload.getEventTime().getSeconds(),
-                        payload.getEventTime().getNanos())
+                        payload.getEventTime().getNanos()),
+                payload.getHeadersMap()
         );
     }
 

src/main/java/io/numaproj/numaflow/reducestreamer/model/Datum.java

@@ -1,6 +1,7 @@
 package io.numaproj.numaflow.reducestreamer.model;
 
 import java.time.Instant;
+import java.util.Map;
 
 /**
  * Datum contains methods to get the payload information.
@@ -26,4 +27,11 @@ public interface Datum {
      * @return returns the watermark
      */
     Instant getWatermark();
+
+    /**
+     * method to get the headers information of the payload
+     *
+     * @return returns the headers in the form of key value pair
+     */
+    public Map<String, String> getHeaders();
 }

src/main/java/io/numaproj/numaflow/sessionreducer/HandlerDatum.java

@@ -4,12 +4,14 @@
 import lombok.AllArgsConstructor;
 
 import java.time.Instant;
+import java.util.Map;
 
 @AllArgsConstructor
 class HandlerDatum implements Datum {
     private byte[] value;
     private Instant watermark;
     private Instant eventTime;
+    private Map<String, String> headers;
 
     @Override
     public Instant getWatermark() {
@@ -25,4 +27,9 @@ public byte[] getValue() {
     public Instant getEventTime() {
         return this.eventTime;
     }
+
+    @Override
+    public Map<String, String> getHeaders() {
+        return this.headers;
+    }
 }

src/main/java/io/numaproj/numaflow/sessionreducer/SupervisorActor.java

@@ -357,7 +357,8 @@ private HandlerDatum constructHandlerDatum(Sessionreduce.SessionReduceRequest.Pa
                         payload.getWatermark().getNanos()),
                 Instant.ofEpochSecond(
                         payload.getEventTime().getSeconds(),
-                        payload.getEventTime().getNanos())
+                        payload.getEventTime().getNanos()),
+                payload.getHeadersMap()
         );
     }
 

src/main/java/io/numaproj/numaflow/sessionreducer/model/Datum.java

@@ -1,6 +1,7 @@
 package io.numaproj.numaflow.sessionreducer.model;
 
 import java.time.Instant;
+import java.util.Map;
 
 /**
  * Datum contains methods to get the payload information.
@@ -26,4 +27,11 @@ public interface Datum {
      * @return returns the watermark
      */
     Instant getWatermark();
+
+    /**
+     * method to get the headers information of the payload
+     *
+     * @return returns the headers in the form of key value pair
+     */
+    public Map<String, String> getHeaders();
 }

src/main/java/io/numaproj/numaflow/sinker/Datum.java

@@ -1,6 +1,7 @@
 package io.numaproj.numaflow.sinker;
 
 import java.time.Instant;
+import java.util.Map;
 
 /**
  * Datum contains methods to get the payload information.
@@ -40,4 +41,11 @@ public interface Datum {
      * @return returns the ID
      */
     String getId();
+
+    /**
+     * method to get the headers information of the payload
+     *
+     * @return returns the headers in the form of key value pair
+     */
+    public Map<String, String> getHeaders();
 }

src/main/java/io/numaproj/numaflow/sinker/HandlerDatum.java

@@ -3,17 +3,19 @@
 import lombok.AllArgsConstructor;
 
 import java.time.Instant;
+import java.util.Map;
 
 @AllArgsConstructor
 class HandlerDatum implements Datum {
 
     // EOF_DATUM is used to indicate the end of the stream.
-    static final HandlerDatum EOF_DATUM = new HandlerDatum(null, null, null, null, null);
+    static final HandlerDatum EOF_DATUM = new HandlerDatum(null, null, null, null, null, null);
     private String[] keys;
     private byte[] value;
     private Instant watermark;
     private Instant eventTime;
     private String id;
+    private Map<String, String> headers;
 
     @Override
     public String[] getKeys() {
@@ -39,4 +41,9 @@ public Instant getEventTime() {
     public String getId() {
         return id;
     }
+
+    @Override
+    public Map<String, String> getHeaders() {
+        return this.headers;
+    }
 }

src/main/java/io/numaproj/numaflow/sinker/Service.java

@@ -112,7 +112,9 @@ private HandlerDatum constructHandlerDatum(SinkOuterClass.SinkRequest d) {
                 Instant.ofEpochSecond(
                         d.getEventTime().getSeconds(),
                         d.getEventTime().getNanos()),
-                d.getId());
+                d.getId(),
+                d.getHeadersMap()
+        );
     }
 
     public SinkOuterClass.SinkResponse buildResponseList(ResponseList responses) {

src/main/java/io/numaproj/numaflow/sourcer/Message.java

@@ -3,6 +3,7 @@
 import lombok.Getter;
 
 import java.time.Instant;
+import java.util.Map;
 
 /**
  * Message is used to wrap the data returned by Sourcer.
@@ -15,6 +16,7 @@ public class Message {
     private final byte[] value;
     private final Offset offset;
     private final Instant eventTime;
+    private final Map<String, String> headers;
 
     /**
      * used to create Message with value, offset and eventTime.
@@ -24,7 +26,7 @@ public class Message {
      * @param eventTime message eventTime
      */
     public Message(byte[] value, Offset offset, Instant eventTime) {
-        this(value, offset, eventTime, null);
+        this(value, offset, eventTime, null, null);
     }
 
     /**
@@ -36,9 +38,23 @@ public Message(byte[] value, Offset offset, Instant eventTime) {
      * @param keys message keys
      */
     public Message(byte[] value, Offset offset, Instant eventTime, String[] keys) {
+        this(value, offset, eventTime, keys, null);
+    }
+
+    /**
+     * used to create Message with value, offset, eventTime, keys and headers.
+     *
+     * @param value message value
+     * @param offset message offset
+     * @param eventTime message eventTime
+     * @param keys message keys
+     * @param headers message headers
+     */
+    public Message(byte[] value, Offset offset, Instant eventTime, String[] keys, Map<String, String> headers) {
         this.value = value;
         this.offset = offset;
         this.eventTime = eventTime;
         this.keys = keys;
+        this.headers = headers;
     }
 }