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.
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  package com.datastax.dse.driver.internal.core.cql.reactive;
  
  import static org.assertj.core.api.Assertions.assertThat;
  
  import com.datastax.dse.driver.api.core.cql.reactive.ReactiveRow;
  import com.datastax.oss.driver.api.core.cql.AsyncResultSet;
  import com.datastax.oss.driver.api.core.cql.ColumnDefinitions;
  import com.datastax.oss.driver.api.core.cql.ExecutionInfo;
  import com.datastax.oss.driver.api.core.cql.Row;
  import com.datastax.oss.driver.api.core.servererrors.UnavailableException;
  import java.util.ArrayList;
  import java.util.List;
  import java.util.concurrent.CompletableFuture;
  import org.junit.Test;
  
  public class ReactiveResultSetSubscriptionTest {
  
    @Test
    public void should_retrieve_entire_result_set() {
      CompletableFuture<AsyncResultSet> future1 = new CompletableFuture<>();
      CompletableFuture<AsyncResultSet> future2 = new CompletableFuture<>();
      CompletableFuture<AsyncResultSet> future3 = new CompletableFuture<>();
      MockAsyncResultSet page1 = new MockAsyncResultSet(3, future2);
      MockAsyncResultSet page2 = new MockAsyncResultSet(3, future3);
      MockAsyncResultSet page3 = new MockAsyncResultSet(3, null);
      TestSubscriber<ReactiveRow> mainSubscriber = new TestSubscriber<>();
      TestSubscriber<ColumnDefinitions> colDefsSubscriber = new TestSubscriber<>();
      TestSubscriber<ExecutionInfo> execInfosSubscriber = new TestSubscriber<>();
      TestSubscriber<Boolean> wasAppliedSubscriber = new TestSubscriber<>();
      ReactiveResultSetSubscription<AsyncResultSet> subscription =
          new ReactiveResultSetSubscription<>(
              mainSubscriber, colDefsSubscriber, execInfosSubscriber, wasAppliedSubscriber);
      mainSubscriber.onSubscribe(subscription);
      subscription.start(() -> future1);
      future1.complete(page1);
      future2.complete(page2);
      future3.complete(page3);
      mainSubscriber.awaitTermination();
      List<Row> expected = new ArrayList<>(page1.currentPage());
      expected.addAll(page2.currentPage());
      expected.addAll(page3.currentPage());
      assertThat(mainSubscriber.getElements()).extracting("row").isEqualTo(expected);
      assertThat(colDefsSubscriber.getElements())
          .hasSize(1)
          .containsExactly(page1.getColumnDefinitions());
      assertThat(execInfosSubscriber.getElements())
          .hasSize(3)
          .containsExactly(
              page1.getExecutionInfo(), page2.getExecutionInfo(), page3.getExecutionInfo());
      assertThat(wasAppliedSubscriber.getElements()).hasSize(1).containsExactly(true);
    }
  
    @Test
    public void should_report_error_on_first_page() {
      CompletableFuture<AsyncResultSet> future1 = new CompletableFuture<>();
      TestSubscriber<ReactiveRow> mainSubscriber = new TestSubscriber<>();
      TestSubscriber<ColumnDefinitions> colDefsSubscriber = new TestSubscriber<>();
      TestSubscriber<ExecutionInfo> execInfosSubscriber = new TestSubscriber<>();
      TestSubscriber<Boolean> wasAppliedSubscriber = new TestSubscriber<>();
      ReactiveResultSetSubscription<AsyncResultSet> subscription =
          new ReactiveResultSetSubscription<>(
              mainSubscriber, colDefsSubscriber, execInfosSubscriber, wasAppliedSubscriber);
      mainSubscriber.onSubscribe(subscription);
      subscription.start(() -> future1);
      future1.completeExceptionally(new UnavailableException(null, null, 0, 0));
      mainSubscriber.awaitTermination();
      assertThat(mainSubscriber.getError()).isNotNull().isInstanceOf(UnavailableException.class);
      assertThat(colDefsSubscriber.getError()).isNotNull().isInstanceOf(UnavailableException.class);
      assertThat(execInfosSubscriber.getError()).isNotNull().isInstanceOf(UnavailableException.class);
      assertThat(wasAppliedSubscriber.getError())
          .isNotNull()
          .isInstanceOf(UnavailableException.class);
    }
  
    @Test
    public void should_report_synchronous_failure_on_first_page() {
      TestSubscriber<ReactiveRow> mainSubscriber = new TestSubscriber<>();
      TestSubscriber<ColumnDefinitions> colDefsSubscriber = new TestSubscriber<>();
      TestSubscriber<ExecutionInfo> execInfosSubscriber = new TestSubscriber<>();
      TestSubscriber<Boolean> wasAppliedSubscriber = new TestSubscriber<>();
      ReactiveResultSetSubscription<AsyncResultSet> subscription =
          new ReactiveResultSetSubscription<>(
              mainSubscriber, colDefsSubscriber, execInfosSubscriber, wasAppliedSubscriber);
      mainSubscriber.onSubscribe(subscription);
      subscription.start(
          () -> {
            throw new IllegalStateException();
          });
      mainSubscriber.awaitTermination();
      assertThat(mainSubscriber.getError()).isNotNull().isInstanceOf(IllegalStateException.class);
      assertThat(colDefsSubscriber.getError()).isNotNull().isInstanceOf(IllegalStateException.class);
      assertThat(execInfosSubscriber.getError())
          .isNotNull()
          .isInstanceOf(IllegalStateException.class);
      assertThat(wasAppliedSubscriber.getError())
          .isNotNull()
          .isInstanceOf(IllegalStateException.class);
    }
  
    @Test
    public void should_report_error_on_intermediary_page() {
      CompletableFuture<AsyncResultSet> future1 = new CompletableFuture<>();
      CompletableFuture<AsyncResultSet> future2 = new CompletableFuture<>();
      MockAsyncResultSet page1 = new MockAsyncResultSet(3, future2);
      TestSubscriber<ReactiveRow> mainSubscriber = new TestSubscriber<>();
      TestSubscriber<ColumnDefinitions> colDefsSubscriber = new TestSubscriber<>();
      TestSubscriber<ExecutionInfo> execInfosSubscriber = new TestSubscriber<>();
      TestSubscriber<Boolean> wasAppliedSubscriber = new TestSubscriber<>();
      ReactiveResultSetSubscription<AsyncResultSet> subscription =
          new ReactiveResultSetSubscription<>(
              mainSubscriber, colDefsSubscriber, execInfosSubscriber, wasAppliedSubscriber);
      mainSubscriber.onSubscribe(subscription);
      subscription.start(() -> future1);
      future1.complete(page1);
      future2.completeExceptionally(new UnavailableException(null, null, 0, 0));
      mainSubscriber.awaitTermination();
      assertThat(mainSubscriber.getElements()).extracting("row").isEqualTo(page1.currentPage());
      assertThat(mainSubscriber.getError()).isNotNull().isInstanceOf(UnavailableException.class);
      // colDefsSubscriber completed normally when page1 arrived
      assertThat(colDefsSubscriber.getError()).isNull();
      assertThat(colDefsSubscriber.getElements())
          .hasSize(1)
          .containsExactly(page1.getColumnDefinitions());
      // execInfosSubscriber completed with error, but should have emitted 1 item for page1
      assertThat(execInfosSubscriber.getElements())
          .hasSize(1)
          .containsExactly(page1.getExecutionInfo());
      assertThat(execInfosSubscriber.getError()).isNotNull().isInstanceOf(UnavailableException.class);
      // colDefsSubscriber completed normally when page1 arrived
      assertThat(wasAppliedSubscriber.getElements()).hasSize(1).containsExactly(true);
      assertThat(wasAppliedSubscriber.getError()).isNull();
    }
  
    @Test
    public void should_handle_empty_non_final_pages() {
      CompletableFuture<AsyncResultSet> future1 = new CompletableFuture<>();
      CompletableFuture<AsyncResultSet> future2 = new CompletableFuture<>();
      CompletableFuture<AsyncResultSet> future3 = new CompletableFuture<>();
      MockAsyncResultSet page1 = new MockAsyncResultSet(10, future2);
      MockAsyncResultSet page2 = new MockAsyncResultSet(0, future3);
      MockAsyncResultSet page3 = new MockAsyncResultSet(10, null);
      TestSubscriber<ReactiveRow> mainSubscriber = new TestSubscriber<>(1);
      TestSubscriber<ColumnDefinitions> colDefsSubscriber = new TestSubscriber<>();
      TestSubscriber<ExecutionInfo> execInfosSubscriber = new TestSubscriber<>();
      TestSubscriber<Boolean> wasAppliedSubscriber = new TestSubscriber<>();
      ReactiveResultSetSubscription<AsyncResultSet> subscription =
          new ReactiveResultSetSubscription<>(
              mainSubscriber, colDefsSubscriber, execInfosSubscriber, wasAppliedSubscriber);
      mainSubscriber.onSubscribe(subscription);
      subscription.start(() -> future1);
      future1.complete(page1);
      future2.complete(page2);
      // emulate backpressure
      subscription.request(1);
      future3.complete(page3);
      subscription.request(Long.MAX_VALUE);
      mainSubscriber.awaitTermination();
      assertThat(mainSubscriber.getError()).isNull();
      List<Row> expected = new ArrayList<>(page1.currentPage());
      expected.addAll(page3.currentPage());
      assertThat(mainSubscriber.getElements()).hasSize(20).extracting("row").isEqualTo(expected);
    }
  }
  