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
   *
   *     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.
   */
  
  // beam-playground:
  //   name: select
  //   description: Select example.
  //   multifile: false
  //   context_line: 126
  //   categories:
  //     - Quickstart
  //   complexity: ADVANCED
  //   tags:
  //     - hellobeam
  
  import org.apache.beam.sdk.Pipeline;
  import org.apache.beam.sdk.io.TextIO;
  import org.apache.beam.sdk.options.PipelineOptions;
  import org.apache.beam.sdk.options.PipelineOptionsFactory;
  import org.apache.beam.sdk.schemas.JavaFieldSchema;
  import org.apache.beam.sdk.schemas.Schema;
  import org.apache.beam.sdk.schemas.annotations.DefaultSchema;
  import org.apache.beam.sdk.schemas.annotations.SchemaCreate;
  import org.apache.beam.sdk.schemas.transforms.Select;
  import org.apache.beam.sdk.transforms.*;
  import org.apache.beam.sdk.values.PCollection;
  import org.apache.beam.sdk.values.Row;
  import org.apache.beam.sdk.values.TypeDescriptor;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  
  public class Task {
      private static final Logger LOG = LoggerFactory.getLogger(Task.class);
  
      @DefaultSchema(JavaFieldSchema.class)
      public static class Game {
          public String userId;
          public String score;
          public String gameId;
          public String date;
  
          @SchemaCreate
          public Game(String userId, String score, String gameId, String date) {
              this.userId = userId;
              this.score = score;
              this.gameId = gameId;
              this.date = date;
          }
  
          @Override
          public String toString() {
              return "Game{" +
                      "userId='" + userId + '\'' +
                      ", score='" + score + '\'' +
                      ", gameId='" + gameId + '\'' +
                      ", date='" + date + '\'' +
                      '}';
          }
      }
  
      // User schema
      @DefaultSchema(JavaFieldSchema.class)
      public static class User {
          public String userId;
          public String userName;
  
          public Game game;
  
          @SchemaCreate
          public User(String userId, String userName, Game game) {
              this.userId = userId;
              this.userName = userName;
              this.game = game;
          }
  
          @Override
          public String toString() {
              return "User{" +
                      "userId='" + userId + '\'' +
                      ", userName='" + userName + '\'' +
                      ", game=" + game +
                      '}';
          }
      }
  
      public static void main(String[] args) {
          PipelineOptions options = PipelineOptionsFactory.fromArgs(args).create();
          Pipeline pipeline = Pipeline.create(options);
  
          Schema shortInfoSchema = Schema.builder()
                  .addStringField("userId")
                  .addStringField("gameId")
                  .build();
  
          Schema gameSchema = Schema.builder()
                  .addStringField("userId")
                  .addStringField("score")
                  .addStringField("gameId")
                  .addStringField("date")
                  .build();
  
          Schema dataSchema = Schema.builder()
                  .addStringField("userId")
                  .addStringField("userName")
                  .addRowField("game", gameSchema)
                  .build();
  
  
          PCollection<User> input = getProgressPCollection(pipeline)
                  .setSchema(dataSchema,
                          TypeDescriptor.of(User.class), row ->
                          {
                              User user = row;
                              Game game = user.game;
  
                              Row gameRow = Row.withSchema(gameSchema)
                                      .addValues(game.userId, game.score, game.gameId, game.date)
                                      .build();
  
                              return Row.withSchema(dataSchema)
                                      .addValues(user.userId, user.userName, gameRow).build();
                          },
                          row -> {
                              String userId = row.getValue("userId");
                              String userName = row.getValue("userName");
                              Row game = row.getValue("game");
  
                              String gameId = game.getValue("gameId");
                              String gameScore = game.getValue("score");
                              String gameDate = game.getValue("date");
                              return new User(userId,userName,
                                      new Game(userId,gameScore,gameId,gameDate));
                          });
  
          // Select [userId] and [userName]
          PCollection<Row> shortInfo = input
                  .apply(Select.<User>fieldNames("userId", "userName").withOutputSchema(shortInfoSchema))
                  .apply("User short info", ParDo.of(new LogOutput<>("Short Info")));
  
          // Select user [game]
          PCollection<Row> game = input
                  .apply(Select.fieldNames("game.*"))
                  .apply("User game", ParDo.of(new LogOutput<>("Game")));
  
          // Flattened row, select all fields
          PCollection<Row> flattened = input
                  .apply(Select.flattenedSchema())
                  .apply("User flatten row", ParDo.of(new LogOutput<>("Flattened")));
  
  
          pipeline.run();
      }
  
      public static PCollection<User> getProgressPCollection(Pipeline pipeline) {
          PCollection<String> rides = pipeline.apply(TextIO.read().from("gs://apache-beam-samples/game/small/gaming_data.csv"));
          final PTransform<PCollection<String>, PCollection<Iterable<String>>> sample = Sample.fixedSizeGlobally(100);
          return rides.apply(sample).apply(Flatten.iterables()).apply(ParDo.of(new ExtractUserProgressFn()));
      }
  
      static class ExtractUserProgressFn extends DoFn<String, User> {
          @ProcessElement
          public void processElement(ProcessContext c) {
              String[] items = c.element().split(",");
              c.output(new User(items[0], items[1], new Game(items[0], items[2], items[3], items[4])));
          }
      }
  
      static class LogOutput<T> extends DoFn<T, T> {
  
          private final String prefix;
  
          LogOutput() {
              this.prefix = "Processing element";
          }
  
          LogOutput(String prefix) {
              this.prefix = prefix;
          }
  
          @ProcessElement
          public void processElement(ProcessContext c) throws Exception {
              LOG.info(prefix + ": {}", c.element());
          }
      }
  }
  