feat: support degree algorithm (#795)

geaflow/geaflow-dsl/geaflow-dsl-plan/src/main/java/org/apache/geaflow/dsl/schema/function/BuildInSqlFunctionTable.java

@@ -39,6 +39,7 @@
 import org.apache.geaflow.dsl.udf.graph.ClusterCoefficient;
 import org.apache.geaflow.dsl.udf.graph.CommonNeighbors;
 import org.apache.geaflow.dsl.udf.graph.ConnectedComponents;
+import org.apache.geaflow.dsl.udf.graph.Degree;
 import org.apache.geaflow.dsl.udf.graph.IncKHopAlgorithm;
 import org.apache.geaflow.dsl.udf.graph.IncMinimumSpanningTree;
 import org.apache.geaflow.dsl.udf.graph.IncWeakConnectedComponents;
@@ -228,6 +229,7 @@ public class BuildInSqlFunctionTable extends ListSqlOperatorTable {
             .add(GeaFlowFunction.of(PageRank.class))
             .add(GeaFlowFunction.of(KHop.class))
             .add(GeaFlowFunction.of(KCore.class))
+            .add(GeaFlowFunction.of(Degree.class))
             .add(GeaFlowFunction.of(IncrementalKCore.class))
             .add(GeaFlowFunction.of(IncMinimumSpanningTree.class))
             .add(GeaFlowFunction.of(ClosenessCentrality.class))

geaflow/geaflow-dsl/geaflow-dsl-plan/src/main/java/org/apache/geaflow/dsl/udf/graph/Degree.java

@@ -0,0 +1,79 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+package org.apache.geaflow.dsl.udf.graph;
+
+import java.util.Iterator;
+import java.util.Optional;
+import org.apache.geaflow.common.type.primitive.IntegerType;
+import org.apache.geaflow.dsl.common.algo.AlgorithmRuntimeContext;
+import org.apache.geaflow.dsl.common.algo.AlgorithmUserFunction;
+import org.apache.geaflow.dsl.common.data.Row;
+import org.apache.geaflow.dsl.common.data.RowVertex;
+import org.apache.geaflow.dsl.common.data.impl.ObjectRow;
+import org.apache.geaflow.dsl.common.function.Description;
+import org.apache.geaflow.dsl.common.types.GraphSchema;
+import org.apache.geaflow.dsl.common.types.StructType;
+import org.apache.geaflow.dsl.common.types.TableField;
+import org.apache.geaflow.model.graph.edge.EdgeDirection;
+
+@Description(name = "degree", description = "built-in udga for Degree")
+public class Degree implements AlgorithmUserFunction<Object, Integer> {
+
+    private AlgorithmRuntimeContext<Object, Integer> context;
+
+    @Override
+    public void init(AlgorithmRuntimeContext<Object, Integer> context, Object[] params) {
+        this.context = context;
+        if (params.length > 0) {
+            throw new IllegalArgumentException(
+                "The degree algorithm takes no arguments, usage: degree()");
+        }
+    }
+
+    @Override
+    public void process(RowVertex vertex, Optional<Row> updatedValues, Iterator<Integer> messages) {
+        updatedValues.ifPresent(vertex::setValue);
+        // Degree needs no message passing: each vertex can count its own
+        // adjacent edges directly in the first (and only) iteration.
+        if (context.getCurrentIterationId() == 1L) {
+            int inDegree = context.loadEdges(EdgeDirection.IN).size();
+            int outDegree = context.loadEdges(EdgeDirection.OUT).size();
+            context.updateVertexValue(ObjectRow.create(inDegree, outDegree));
+        }
+    }
+
+    @Override
+    public void finish(RowVertex graphVertex, Optional<Row> updatedValues) {
+        updatedValues.ifPresent(graphVertex::setValue);
+        int inDegree = (int) graphVertex.getValue().getField(0, IntegerType.INSTANCE);
+        int outDegree = (int) graphVertex.getValue().getField(1, IntegerType.INSTANCE);
+        context.take(ObjectRow.create(graphVertex.getId(), inDegree, outDegree));
+    }
+
+    @Override
+    public StructType getOutputType(GraphSchema graphSchema) {
+        return new StructType(
+            new TableField("id", graphSchema.getIdType(), false),
+            new TableField("in_degree", IntegerType.INSTANCE, false),
+            new TableField("out_degree", IntegerType.INSTANCE, false)
+        );
+    }
+
+}

geaflow/geaflow-dsl/geaflow-dsl-runtime/src/test/java/org/apache/geaflow/dsl/runtime/query/GQLAlgorithmTest.java

@@ -115,6 +115,15 @@ public void testAlgorithmKCore() throws Exception {
             .checkSinkResult();
     }
 
+    @Test
+    public void testAlgorithmDegree() throws Exception {
+        QueryTester
+            .build()
+            .withQueryPath("/query/gql_algorithm_degree.sql")
+            .execute()
+            .checkSinkResult();
+    }
+
     @Test
     public void testAlgorithmClosenessCentrality() throws Exception {
         QueryTester

geaflow/geaflow-dsl/geaflow-dsl-runtime/src/test/resources/expect/gql_algorithm_degree.txt

@@ -0,0 +1,6 @@
+1,1,3
+2,0,1
+3,2,1
+4,2,2
+5,1,2
+6,3,0

geaflow/geaflow-dsl/geaflow-dsl-runtime/src/test/resources/query/gql_algorithm_degree.sql

@@ -0,0 +1,79 @@
+/*
+ * Licensed to the Apache Software Foundation (ASF) under one
+ * or more contributor license agreements.  See the NOTICE file
+ * distributed with this work for additional information
+ * regarding copyright ownership.  The ASF licenses this file
+ * to you under the Apache License, Version 2.0 (the
+ * "License"); you may not use this file except in compliance
+ * with the License.  You may obtain a copy of the License at
+ *
+ *   http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing,
+ * software distributed under the License is distributed on an
+ * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+ * KIND, either express or implied.  See the License for the
+ * specific language governing permissions and limitations
+ * under the License.
+ */
+
+set geaflow.dsl.window.size = -1;
+set geaflow.dsl.ignore.exception = true;
+
+CREATE GRAPH IF NOT EXISTS g4 (
+  Vertex v4 (
+    vid varchar ID,
+    vvalue int
+  ),
+  Edge e4 (
+    srcId varchar SOURCE ID,
+    targetId varchar DESTINATION ID
+  )
+) WITH (
+  storeType='rocksdb',
+  shardCount = 1
+);
+
+CREATE TABLE IF NOT EXISTS v_source (
+    v_id varchar,
+    v_value int,
+    ts varchar,
+    type varchar
+) WITH (
+  type='file',
+  geaflow.dsl.file.path = 'resource:///input/test_vertex'
+);
+
+CREATE TABLE IF NOT EXISTS e_source (
+    src_id varchar,
+    dst_id varchar
+) WITH (
+  type='file',
+  geaflow.dsl.file.path = 'resource:///input/test_edge'
+);
+
+CREATE TABLE IF NOT EXISTS tbl_result (
+  v_id varchar,
+  in_degree int,
+  out_degree int
+) WITH (
+  type='file',
+   geaflow.dsl.file.path = '${target}'
+);
+
+USE GRAPH g4;
+
+INSERT INTO g4.v4(vid, vvalue)
+SELECT
+v_id, v_value
+FROM v_source;
+
+INSERT INTO g4.e4(srcId, targetId)
+SELECT
+ src_id, dst_id
+FROM e_source;
+
+INSERT INTO tbl_result(v_id, in_degree, out_degree)
+CALL degree() YIELD (vid, inDegree, outDegree)
+RETURN vid, inDegree, outDegree
+;