/*
 * 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.splunk;

import java.util.List;
import org.apache.beam.sdk.testing.NeedsRunner;
import org.apache.beam.sdk.testing.PAssert;
import org.apache.beam.sdk.testing.TestPipeline;
import org.apache.beam.sdk.transforms.Create;
import org.apache.beam.sdk.values.PCollection;
import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.base.Joiner;
import org.apache.beam.vendor.guava.v26_0_jre.com.google.common.collect.ImmutableList;
import org.junit.Rule;
import org.junit.Test;
import org.junit.experimental.categories.Category;
import org.mockserver.client.MockServerClient;
import org.mockserver.junit.MockServerRule;
import org.mockserver.model.HttpRequest;
import org.mockserver.model.HttpResponse;
import org.mockserver.verify.VerificationTimes;

/** Unit tests for {@link SplunkIO} class. */
public class SplunkIOTest {

  private static final String EXPECTED_PATH = "/" + HttpEventPublisher.HEC_URL_PATH;

  @Rule public final transient TestPipeline pipeline = TestPipeline.create();

  // We create a MockServerRule to simulate an actual Splunk HEC server.
  @Rule public MockServerRule mockServerRule = new MockServerRule(this);
  private MockServerClient mockServerClient;

  @Test
  @Category(NeedsRunner.class)
  public void successfulSplunkIOMultiBatchNoParallelismTest() {

    // Create server expectation for success.
    mockServerListening(200);

    int testPort = mockServerRule.getPort();
    String url = Joiner.on(':').join("http://localhost", testPort);
    String token = "test-token";

    List<SplunkEvent> testEvents =
        ImmutableList.of(
            SplunkEvent.newBuilder()
                .withEvent("test-event-1")
                .withHost("test-host-1")
                .withIndex("test-index-1")
                .withSource("test-source-1")
                .withSourceType("test-source-type-1")
                .withTime(12345L)
                .create(),
            SplunkEvent.newBuilder()
                .withEvent("test-event-2")
                .withHost("test-host-2")
                .withIndex("test-index-2")
                .withSource("test-source-2")
                .withSourceType("test-source-type-2")
                .withTime(12345L)
                .create());

    PCollection<SplunkWriteError> actual =
        pipeline
            .apply("Create Input data", Create.of(testEvents)) // .withCoder(SplunkEventCoder.of()))
            .apply(
                "SplunkIO",
                SplunkIO.write(url, token).withParallelism(1).withBatchCount(testEvents.size()));

    // All successful responses.
    PAssert.that(actual).empty();

    pipeline.run();

    // Server received exactly one POST request.
    mockServerClient.verify(HttpRequest.request(EXPECTED_PATH), VerificationTimes.once());
  }

  @Test
  @Category(NeedsRunner.class)
  public void successfulSplunkIOMultiBatchParallelismTest() {

    // Create server expectation for success.
    mockServerListening(200);

    int testPort = mockServerRule.getPort();
    int testParallelism = 2;
    String url = Joiner.on(':').join("http://localhost", testPort);
    String token = "test-token";

    List<SplunkEvent> testEvents =
        ImmutableList.of(
            SplunkEvent.newBuilder()
                .withEvent("test-event-1")
                .withHost("test-host-1")
                .withIndex("test-index-1")
                .withSource("test-source-1")
                .withSourceType("test-source-type-1")
                .withTime(12345L)
                .create(),
            SplunkEvent.newBuilder()
                .withEvent("test-event-2")
                .withHost("test-host-2")
                .withIndex("test-index-2")
                .withSource("test-source-2")
                .withSourceType("test-source-type-2")
                .withTime(12345L)
                .create());

    PCollection<SplunkWriteError> actual =
        pipeline
            .apply("Create Input data", Create.of(testEvents)) // .withCoder(SplunkEventCoder.of()))
            .apply(
                "SplunkIO",
                SplunkIO.write(url, token)
                    .withParallelism(testParallelism)
                    .withBatchCount(testEvents.size()));

    // All successful responses.
    PAssert.that(actual).empty();

    pipeline.run();

    // Server received exactly one POST request per parallelism
    mockServerClient.verify(
        HttpRequest.request(EXPECTED_PATH), VerificationTimes.atMost(testParallelism));
  }

  @Test
  @Category(NeedsRunner.class)
  public void successfulSplunkIOSingleBatchParallelismTest() {

    // Create server expectation for success.
    mockServerListening(200);

    int testPort = mockServerRule.getPort();
    int testParallelism = 2;
    String url = Joiner.on(':').join("http://localhost", testPort);
    String token = "test-token";

    List<SplunkEvent> testEvents =
        ImmutableList.of(
            SplunkEvent.newBuilder()
                .withEvent("test-event-1")
                .withHost("test-host-1")
                .withIndex("test-index-1")
                .withSource("test-source-1")
                .withSourceType("test-source-type-1")
                .withTime(12345L)
                .create(),
            SplunkEvent.newBuilder()
                .withEvent("test-event-2")
                .withHost("test-host-2")
                .withIndex("test-index-2")
                .withSource("test-source-2")
                .withSourceType("test-source-type-2")
                .withTime(12345L)
                .create());

    PCollection<SplunkWriteError> actual =
        pipeline
            .apply("Create Input data", Create.of(testEvents)) // .withCoder(SplunkEventCoder.of()))
            .apply(
                "SplunkIO",
                SplunkIO.write(url, token).withParallelism(testParallelism).withBatchCount(1));

    // All successful responses.
    PAssert.that(actual).empty();

    pipeline.run();

    // Server received exactly 1 post request per SplunkEvent
    mockServerClient.verify(
        HttpRequest.request(EXPECTED_PATH), VerificationTimes.exactly(testEvents.size()));
  }

  private void mockServerListening(int statusCode) {
    mockServerClient
        .when(HttpRequest.request(EXPECTED_PATH))
        .respond(HttpResponse.response().withStatusCode(statusCode));
  }
}
