diff --git a/dhp-workflows/dhp-actionmanager/src/main/java/eu/dnetlib/dhp/actionmanager/PromoteActionSetFromHDFSFunctions.java b/dhp-workflows/dhp-actionmanager/src/main/java/eu/dnetlib/dhp/actionmanager/PromoteActionSetFromHDFSFunctions.java
index 95b231a702..994989e45a 100644
--- a/dhp-workflows/dhp-actionmanager/src/main/java/eu/dnetlib/dhp/actionmanager/PromoteActionSetFromHDFSFunctions.java
+++ b/dhp-workflows/dhp-actionmanager/src/main/java/eu/dnetlib/dhp/actionmanager/PromoteActionSetFromHDFSFunctions.java
@@ -3,7 +3,6 @@ package eu.dnetlib.dhp.actionmanager;
 import eu.dnetlib.dhp.schema.oaf.Oaf;
 import eu.dnetlib.dhp.schema.oaf.OafEntity;
 import eu.dnetlib.dhp.schema.oaf.Relation;
-import org.apache.spark.api.java.function.FilterFunction;
 import org.apache.spark.api.java.function.MapFunction;
 import org.apache.spark.api.java.function.ReduceFunction;
 import org.apache.spark.sql.Dataset;
@@ -21,20 +20,12 @@ import java.util.function.Function;
 public class PromoteActionSetFromHDFSFunctions {
 
     public static <T extends Oaf> Dataset<T> joinOafEntityWithActionPayloadAndMerge(Dataset<T> oafDS,
-                                                                                    Dataset<String> actionPayloadDS,
+                                                                                    Dataset<T> actionPayloadOafDS,
                                                                                     SerializableSupplier<Function<T, String>> oafIdFn,
-                                                                                    SerializableSupplier<BiFunction<String, Class<T>, T>> actionPayloadToOafFn,
                                                                                     SerializableSupplier<BiFunction<T, T, T>> mergeAndGetFn,
                                                                                     Class<T> clazz) {
-        Dataset<Tuple2<String, T>> oafWithIdDS = oafDS
-                .map((MapFunction<T, Tuple2<String, T>>) value -> new Tuple2<>(oafIdFn.get().apply(value), value),
-                        Encoders.tuple(Encoders.STRING(), Encoders.kryo(clazz)));
-
-        Dataset<Tuple2<String, T>> actionPayloadWithIdDS = actionPayloadDS
-                .map((MapFunction<String, T>) value -> actionPayloadToOafFn.get().apply(value, clazz), Encoders.kryo(clazz))
-                .filter((FilterFunction<T>) Objects::nonNull)
-                .map((MapFunction<T, Tuple2<String, T>>) value -> new Tuple2<>(oafIdFn.get().apply(value), value),
-                        Encoders.tuple(Encoders.STRING(), Encoders.kryo(clazz)));
+        Dataset<Tuple2<String, T>> oafWithIdDS = mapToTupleWithId(oafDS, oafIdFn, clazz);
+        Dataset<Tuple2<String, T>> actionPayloadWithIdDS = mapToTupleWithId(actionPayloadOafDS, oafIdFn, clazz);
 
         return oafWithIdDS
                 .joinWith(actionPayloadWithIdDS, oafWithIdDS.col("_1").equalTo(actionPayloadWithIdDS.col("_1")), "left_outer")
@@ -48,6 +39,14 @@ public class PromoteActionSetFromHDFSFunctions {
                 }, Encoders.kryo(clazz));
     }
 
+    private static <T extends Oaf> Dataset<Tuple2<String, T>> mapToTupleWithId(Dataset<T> ds,
+                                                                               SerializableSupplier<Function<T, String>> idFn,
+                                                                               Class<T> clazz) {
+        return ds
+                .map((MapFunction<T, Tuple2<String, T>>) value -> new Tuple2<>(idFn.get().apply(value), value),
+                        Encoders.tuple(Encoders.STRING(), Encoders.kryo(clazz)));
+    }
+
     public static <T extends Oaf> Dataset<T> groupOafByIdAndMerge(Dataset<T> oafDS,
                                                                   SerializableSupplier<Function<T, String>> oafIdFn,
                                                                   SerializableSupplier<BiFunction<T, T, T>> mergeAndGetFn,
diff --git a/dhp-workflows/dhp-actionmanager/src/test/java/eu/dnetlib/dhp/actionmanager/PromoteActionSetFromHDFSFunctionsTest.java b/dhp-workflows/dhp-actionmanager/src/test/java/eu/dnetlib/dhp/actionmanager/PromoteActionSetFromHDFSFunctionsTest.java
index a4db01f7ad..a05dac9107 100644
--- a/dhp-workflows/dhp-actionmanager/src/test/java/eu/dnetlib/dhp/actionmanager/PromoteActionSetFromHDFSFunctionsTest.java
+++ b/dhp-workflows/dhp-actionmanager/src/test/java/eu/dnetlib/dhp/actionmanager/PromoteActionSetFromHDFSFunctionsTest.java
@@ -1,7 +1,5 @@
 package eu.dnetlib.dhp.actionmanager;
 
-import com.fasterxml.jackson.databind.JsonNode;
-import com.fasterxml.jackson.databind.ObjectMapper;
 import eu.dnetlib.dhp.schema.oaf.Oaf;
 import org.apache.spark.SparkConf;
 import org.apache.spark.sql.Dataset;
@@ -11,7 +9,6 @@ import org.junit.AfterClass;
 import org.junit.BeforeClass;
 import org.junit.Test;
 
-import java.io.IOException;
 import java.util.Arrays;
 import java.util.List;
 import java.util.function.BiFunction;
@@ -50,38 +47,24 @@ public class PromoteActionSetFromHDFSFunctionsTest {
         );
         Dataset<OafImpl> oafDS = spark.createDataset(oafData, Encoders.bean(OafImpl.class));
 
-        List<String> actionPayloadData = Arrays.asList(
-                createActionPayload(id1),
-                createActionPayload(id2), createActionPayload(id2),
-                createActionPayload(id3), createActionPayload(id3), createActionPayload(id3)
+        List<OafImpl> actionPayloadData = Arrays.asList(
+                createOafImpl(id1),
+                createOafImpl(id2), createOafImpl(id2),
+                createOafImpl(id3), createOafImpl(id3), createOafImpl(id3)
         );
-        Dataset<String> actionPayloadDS = spark.createDataset(actionPayloadData, Encoders.STRING());
+        Dataset<OafImpl> actionPayloadDS = spark.createDataset(actionPayloadData, Encoders.bean(OafImpl.class));
 
         SerializableSupplier<Function<OafImpl, String>> oafIdFn = () -> OafImpl::getId;
-        SerializableSupplier<BiFunction<String, Class<OafImpl>, OafImpl>> actionPayloadToOafFn = () -> (s, clazz) -> {
-            try {
-                JsonNode jsonNode = new ObjectMapper().readTree(s);
-                String id = jsonNode.at("/id").asText();
-                return createOafImpl(id);
-            } catch (IOException e) {
-                throw new RuntimeException(e);
-            }
-        };
-        SerializableSupplier<BiFunction<OafImpl, OafImpl, OafImpl>> mergeAndGetFn = () -> (x, y) -> {
-            x.mergeFrom(y);
-            return x;
-        };
+        SerializableSupplier<BiFunction<OafImpl, OafImpl, OafImpl>> mergeAndGetFn = () -> OafImpl::mergeAngGet;
 
         // when
         List<OafImpl> results = PromoteActionSetFromHDFSFunctions
                 .joinOafEntityWithActionPayloadAndMerge(oafDS,
                         actionPayloadDS,
                         oafIdFn,
-                        actionPayloadToOafFn,
                         mergeAndGetFn,
                         OafImpl.class)
                 .collectAsList();
-//        System.out.println(results.stream().map(x -> String.format("%s:%d", x.getId(), x.merged)).collect(Collectors.joining(",")));
 
         // then
         assertEquals(7, results.size());
@@ -95,6 +78,8 @@ public class PromoteActionSetFromHDFSFunctionsTest {
                 case "id4":
                     assertEquals(1, result.merged);
                     break;
+                default:
+                    throw new RuntimeException();
             }
         });
     }
@@ -112,10 +97,7 @@ public class PromoteActionSetFromHDFSFunctionsTest {
         );
         Dataset<OafImpl> oafDS = spark.createDataset(oafData, Encoders.bean(OafImpl.class));
         SerializableSupplier<Function<OafImpl, String>> idFn = () -> OafImpl::getId;
-        SerializableSupplier<BiFunction<OafImpl, OafImpl, OafImpl>> mergeAndGetFn = () -> (x, y) -> {
-            x.mergeFrom(y);
-            return x;
-        };
+        SerializableSupplier<BiFunction<OafImpl, OafImpl, OafImpl>> mergeAndGetFn = () -> OafImpl::mergeAngGet;
 
         // when
         List<OafImpl> results = PromoteActionSetFromHDFSFunctions
@@ -124,7 +106,6 @@ public class PromoteActionSetFromHDFSFunctionsTest {
                         mergeAndGetFn,
                         OafImpl.class)
                 .collectAsList();
-//        System.out.println(results.stream().map(x -> String.format("%s:%d", x.getId(), x.merged)).collect(Collectors.joining(",")));
 
         // then
         assertEquals(3, results.size());
@@ -139,6 +120,8 @@ public class PromoteActionSetFromHDFSFunctionsTest {
                 case "id3":
                     assertEquals(3, result.merged);
                     break;
+                default:
+                    throw new RuntimeException();
             }
         });
     }
@@ -147,8 +130,9 @@ public class PromoteActionSetFromHDFSFunctionsTest {
         private String id;
         private int merged = 1;
 
-        public void mergeFrom(Oaf e) {
-            merged += ((OafImpl) e).merged;
+        public OafImpl mergeAngGet(OafImpl e) {
+            merged += e.merged;
+            return this;
         }
 
         public String getId() {
@@ -174,7 +158,4 @@ public class PromoteActionSetFromHDFSFunctionsTest {
         return x;
     }
 
-    private static String createActionPayload(String id) {
-        return String.format("{\"id\":\"%s\"}", id);
-    }
 }