| /* |
| * 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.beam.sdk.io.mongodb; |
| |
| import static org.apache.beam.vendor.guava.v20_0.com.google.common.base.Preconditions.checkArgument; |
| |
| import com.google.auto.value.AutoValue; |
| import com.mongodb.BasicDBObject; |
| import com.mongodb.MongoClient; |
| import com.mongodb.client.MongoCollection; |
| import com.mongodb.client.MongoCursor; |
| import com.mongodb.client.model.Projections; |
| import java.util.Collections; |
| import java.util.List; |
| import javax.annotation.Nullable; |
| import org.apache.beam.sdk.annotations.Experimental; |
| import org.apache.beam.sdk.transforms.SerializableFunction; |
| import org.bson.BsonDocument; |
| import org.bson.Document; |
| import org.bson.conversions.Bson; |
| |
| /** Builds a MongoDB FindQuery object. */ |
| @Experimental(Experimental.Kind.SOURCE_SINK) |
| @AutoValue |
| public abstract class FindQuery |
| implements SerializableFunction<MongoCollection<Document>, MongoCursor<Document>> { |
| |
| @Nullable |
| abstract BsonDocument filters(); |
| |
| abstract int limit(); |
| |
| abstract List<String> projection(); |
| |
| private static Builder builder() { |
| return new AutoValue_FindQuery.Builder() |
| .setLimit(0) |
| .setProjection(Collections.emptyList()) |
| .setFilters(new BsonDocument()); |
| } |
| |
| abstract Builder toBuilder(); |
| |
| public static FindQuery create() { |
| return builder().build(); |
| } |
| |
| @AutoValue.Builder |
| abstract static class Builder { |
| abstract Builder setFilters(@Nullable BsonDocument filters); |
| |
| abstract Builder setLimit(int limit); |
| |
| abstract Builder setProjection(List<String> projection); |
| |
| abstract FindQuery build(); |
| } |
| |
| /** Sets the filters to find. */ |
| private FindQuery withFilters(BsonDocument filters) { |
| return toBuilder().setFilters(filters).build(); |
| } |
| |
| /** Convert the Bson filters into a BsonDocument via default encoding. */ |
| static BsonDocument bson2BsonDocument(Bson filters) { |
| return filters.toBsonDocument(BasicDBObject.class, MongoClient.getDefaultCodecRegistry()); |
| } |
| |
| /** Sets the filters to find. */ |
| public FindQuery withFilters(Bson filters) { |
| return withFilters(bson2BsonDocument(filters)); |
| } |
| |
| /** Sets the limit of documents to find. */ |
| public FindQuery withLimit(int limit) { |
| return toBuilder().setLimit(limit).build(); |
| } |
| |
| /** Sets the projection. */ |
| public FindQuery withProjection(List<String> projection) { |
| checkArgument(projection != null, "projection can not be null"); |
| return toBuilder().setProjection(projection).build(); |
| } |
| |
| @Override |
| public MongoCursor<Document> apply(MongoCollection<Document> collection) { |
| return collection |
| .find() |
| .filter(filters()) |
| .limit(limit()) |
| .projection(Projections.include(projection())) |
| .iterator(); |
| } |
| } |