hugegraph-server/hugegraph-api/src/main/java/org/apache/hugegraph/api/traversers/AdamicAdarAPI.java

/*
 * 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.hugegraph.api.traversers;

import static org.apache.hugegraph.traversal.algorithm.HugeTraverser.DEFAULT_ELEMENTS_LIMIT;
import static org.apache.hugegraph.traversal.algorithm.HugeTraverser.DEFAULT_MAX_DEGREE;

import io.swagger.v3.oas.annotations.tags.Tag;
import jakarta.inject.Singleton;
import jakarta.ws.rs.DefaultValue;
import jakarta.ws.rs.GET;
import jakarta.ws.rs.Path;
import jakarta.ws.rs.PathParam;
import jakarta.ws.rs.Produces;
import jakarta.ws.rs.QueryParam;
import jakarta.ws.rs.core.Context;

import org.apache.hugegraph.HugeGraph;
import org.apache.hugegraph.api.API;
import org.apache.hugegraph.api.graph.EdgeAPI;
import org.apache.hugegraph.api.graph.VertexAPI;
import org.apache.hugegraph.backend.id.Id;
import org.apache.hugegraph.core.GraphManager;
import org.apache.hugegraph.traversal.algorithm.PredictionTraverser;
import org.apache.hugegraph.type.define.Directions;
import org.apache.hugegraph.util.E;
import org.apache.hugegraph.util.JsonUtil;
import com.codahale.metrics.annotation.Timed;
import com.google.common.collect.ImmutableMap;

/**
 * AdamicAdar is one of the prediction algorithms in graph, you can get more
 * info and definition in:
 * https://en.wikipedia.org/wiki/Adamic/Adar_index
 */
@Path("graphs/{graph}/traversers/adamicadar")
@Singleton
@Tag(name = "AdamicAdarAPI")
public class AdamicAdarAPI extends API {

    @GET
    @Timed
    @Produces(APPLICATION_JSON_WITH_CHARSET)
    public String get(@Context GraphManager manager,
                      @PathParam("graph") String graph,
                      @QueryParam("vertex") String current,
                      @QueryParam("other") String other,
                      @QueryParam("direction") String direction,
                      @QueryParam("label") String edgeLabel,
                      @QueryParam("max_degree")
                      @DefaultValue(DEFAULT_MAX_DEGREE) long maxDegree,
                      @QueryParam("limit")
                      @DefaultValue(DEFAULT_ELEMENTS_LIMIT) int limit) {
        LOG.debug("Graph [{}] get adamic adar between '{}' and '{}' with " +
                  "direction {}, edge label {}, max degree '{}' and limit '{}'",
                  graph, current, other, direction, edgeLabel, maxDegree,
                  limit);

        Id sourceId = VertexAPI.checkAndParseVertexId(current);
        Id targetId = VertexAPI.checkAndParseVertexId(other);
        E.checkArgument(!current.equals(other),
                        "The source and target vertex id can't be same");
        Directions dir = Directions.convert(EdgeAPI.parseDirection(direction));

        HugeGraph g = graph(manager, graph);
        try (PredictionTraverser traverser = new PredictionTraverser(g)) {
            double score = traverser.adamicAdar(sourceId, targetId, dir,
                                                edgeLabel, maxDegree, limit);
            return JsonUtil.toJson(ImmutableMap.of("adamic_adar", score));
        }
    }
}