content: /**
   * 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
   * <p>
   * http://www.apache.org/licenses/LICENSE-2.0
   * <p>
   * 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.atlas.web.rest;
  
  import org.apache.atlas.AtlasConfiguration;
  import org.apache.atlas.AtlasErrorCode;
  import org.apache.atlas.annotation.Timed;
  import org.apache.atlas.discovery.AtlasLineageService;
  import org.apache.atlas.exception.AtlasBaseException;
  import org.apache.atlas.model.TypeCategory;
  import org.apache.atlas.model.lineage.AtlasLineageInfo;
  import org.apache.atlas.model.lineage.AtlasLineageInfo.LineageDirection;
  import org.apache.atlas.model.lineage.LineageOnDemandConstraints;
  import org.apache.atlas.repository.store.graph.v2.AtlasGraphUtilsV2;
  import org.apache.atlas.type.AtlasEntityType;
  import org.apache.atlas.type.AtlasTypeRegistry;
  import org.apache.atlas.utils.AtlasPerfTracer;
  import org.apache.atlas.web.util.Servlets;
  import org.apache.commons.collections.MapUtils;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.springframework.stereotype.Service;
  
  import javax.inject.Inject;
  import javax.inject.Singleton;
  import javax.servlet.http.HttpServletRequest;
  import javax.ws.rs.Consumes;
  import javax.ws.rs.DefaultValue;
  import javax.ws.rs.GET;
  import javax.ws.rs.POST;
  import javax.ws.rs.Path;
  import javax.ws.rs.PathParam;
  import javax.ws.rs.Produces;
  import javax.ws.rs.QueryParam;
  import javax.ws.rs.core.Context;
  import javax.ws.rs.core.MediaType;
  
  import java.util.HashMap;
  import java.util.Map;
  
  /**
   * REST interface for an entity's lineage information
   */
  @Path("v2/lineage")
  @Singleton
  @Service
  @Consumes({Servlets.JSON_MEDIA_TYPE, MediaType.APPLICATION_JSON})
  @Produces({Servlets.JSON_MEDIA_TYPE, MediaType.APPLICATION_JSON})
  public class LineageREST {
      private static final Logger LOG      = LoggerFactory.getLogger(LineageREST.class);
      private static final Logger PERF_LOG = AtlasPerfTracer.getPerfLogger("rest.LineageREST");
  
      private static final String PREFIX_ATTR       = "attr:";
      private static final String DEFAULT_DIRECTION = "BOTH";
      private static final String DEFAULT_DEPTH     = "3";
  
      private final AtlasTypeRegistry   typeRegistry;
      private final AtlasLineageService atlasLineageService;
  
      @Context
      private HttpServletRequest httpServletRequest;
  
      @Inject
      public LineageREST(AtlasTypeRegistry typeRegistry, AtlasLineageService atlasLineageService) {
          this.typeRegistry        = typeRegistry;
          this.atlasLineageService = atlasLineageService;
      }
  
      /**
       * Returns lineage info about entity.
       *
       * @param guid - unique entity id
       * @param direction - input, output or both
       * @param depth - number of hops for lineage
       * @return AtlasLineageInfo
       * @throws AtlasBaseException
       * @HTTP 200 If Lineage exists for the given entity
       * @HTTP 400 Bad query parameters
       * @HTTP 404 If no lineage is found for the given entity
       */
      @GET
      @Path("/{guid}")
      @Timed
      public AtlasLineageInfo getLineageGraph(@PathParam("guid") String guid, @QueryParam("direction") @DefaultValue(DEFAULT_DIRECTION) LineageDirection direction, @QueryParam("depth") @DefaultValue(DEFAULT_DEPTH) int depth) throws AtlasBaseException {
          Servlets.validateQueryParamLength("guid", guid);
  
          AtlasPerfTracer perf = null;
  
          try {
              if (AtlasPerfTracer.isPerfTraceEnabled(PERF_LOG)) {
                  perf = AtlasPerfTracer.getPerfTracer(PERF_LOG, "LineageREST.getLineageGraph(" + guid + "," + direction + "," + depth + ")");
              }
  
              return atlasLineageService.getAtlasLineageInfo(guid, direction, depth);
          } finally {
              AtlasPerfTracer.log(perf);
          }
      }
  
      /**
       * Returns lineage info about entity.
       *
       * @return AtlasLineageInfo
       * @throws AtlasBaseException
       * @HTTP 200 If Lineage exists for the given entity
       * @HTTP 400 Bad query parameters
       * @HTTP 404 If no lineage is found for the given entity
       */
      @POST
      @Path("/{guid}")
      @Consumes(Servlets.JSON_MEDIA_TYPE)
      @Produces(Servlets.JSON_MEDIA_TYPE)
      @Timed
      public AtlasLineageInfo getLineageGraph(@PathParam("guid") String guid, Map<String, LineageOnDemandConstraints> lineageConstraintsMapByGuid) throws AtlasBaseException {
          if (!AtlasConfiguration.LINEAGE_ON_DEMAND_ENABLED.getBoolean()) {
              LOG.warn("LineageREST: {}", AtlasErrorCode.LINEAGE_ON_DEMAND_NOT_ENABLED.getFormattedErrorMessage(AtlasConfiguration.LINEAGE_ON_DEMAND_ENABLED.getPropertyName()));
  
              throw new AtlasBaseException(AtlasErrorCode.LINEAGE_ON_DEMAND_NOT_ENABLED, AtlasConfiguration.LINEAGE_ON_DEMAND_ENABLED.getPropertyName());
          }
  
          Servlets.validateQueryParamLength("guid", guid);
  
          AtlasPerfTracer perf = null;
  
          try {
              if (AtlasPerfTracer.isPerfTraceEnabled(PERF_LOG)) {
                  perf = AtlasPerfTracer.getPerfTracer(PERF_LOG, "LineageREST.getLineageGraph(" + guid + "," + lineageConstraintsMapByGuid + ")");
              }
  
              return atlasLineageService.getAtlasLineageInfo(guid, lineageConstraintsMapByGuid);
          } finally {
              AtlasPerfTracer.log(perf);
          }
      }
  
      /**
       * Returns lineage info about entity.
       * <p>
       * In addition to the typeName path parameter, attribute key-value pair(s) can be provided in the following format
       * <p>
       * attr:<attrName>=<attrValue>
       * <p>
       * NOTE: The attrName and attrValue should be unique across entities, eg. qualifiedName
       *
       * @param typeName - typeName of entity
       * @param direction - input, output or both
       * @param depth - number of hops for lineage
       * @return AtlasLineageInfo
       * @throws AtlasBaseException
       * @HTTP 200 If Lineage exists for the given entity
       * @HTTP 400 Bad query parameters
       * @HTTP 404 If no lineage is found for the given entity
       */
      @GET
      @Path("/uniqueAttribute/type/{typeName}")
      @Consumes(Servlets.JSON_MEDIA_TYPE)
      @Produces(Servlets.JSON_MEDIA_TYPE)
      @Timed
      public AtlasLineageInfo getLineageByUniqueAttribute(@PathParam("typeName") String typeName, @QueryParam("direction") @DefaultValue(DEFAULT_DIRECTION) LineageDirection direction, @QueryParam("depth") @DefaultValue(DEFAULT_DEPTH) int depth, @Context HttpServletRequest servletRequest) throws AtlasBaseException {
          Servlets.validateQueryParamLength("typeName", typeName);
  
          AtlasPerfTracer perf = null;
  
          try {
              AtlasEntityType     entityType = ensureEntityType(typeName);
              Map<String, Object> attributes = getAttributes(servletRequest);
              String              guid       = AtlasGraphUtilsV2.getGuidByUniqueAttributes(entityType, attributes);
  
              if (AtlasPerfTracer.isPerfTraceEnabled(PERF_LOG)) {
                  perf = AtlasPerfTracer.getPerfTracer(PERF_LOG, "LineageREST.getLineageByUniqueAttribute(" + typeName + "," + attributes + "," + direction + "," + depth + ")");
              }
  
              return atlasLineageService.getAtlasLineageInfo(guid, direction, depth);
          } finally {
              AtlasPerfTracer.log(perf);
          }
      }
  
      private Map<String, Object> getAttributes(HttpServletRequest request) {
          Map<String, Object> attributes = new HashMap<>();
  
          if (MapUtils.isNotEmpty(request.getParameterMap())) {
              for (Map.Entry<String, String[]> e : request.getParameterMap().entrySet()) {
                  String key = e.getKey();
  
                  if (key != null && key.startsWith(PREFIX_ATTR)) {
                      String[] values = e.getValue();
                      String   value  = values != null && values.length > 0 ? values[0] : null;
  
                      attributes.put(key.substring(PREFIX_ATTR.length()), value);
                  }
              }
          }
  
          return attributes;
      }
  
      private AtlasEntityType ensureEntityType(String typeName) throws AtlasBaseException {
          AtlasEntityType ret = typeRegistry.getEntityTypeByName(typeName);
  
          if (ret == null) {
              throw new AtlasBaseException(AtlasErrorCode.TYPE_NAME_INVALID, TypeCategory.ENTITY.name(), typeName);
          }
  
          return ret;
      }
  }
  