google-nomulus/javatests/google/registry/testing/TaskQueueHelper.java

// Copyright 2016 The Domain Registry Authors. All Rights Reserved.
//
// Licensed 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 google.registry.testing;

import static com.google.appengine.tools.development.testing.LocalTaskQueueTestConfig.getLocalTaskQueue;
import static com.google.common.base.Preconditions.checkState;
import static com.google.common.base.Predicates.in;
import static com.google.common.base.Predicates.not;
import static com.google.common.collect.Iterables.getFirst;
import static com.google.common.collect.Iterables.transform;
import static com.google.common.collect.Multisets.containsOccurrences;
import static com.google.common.truth.Truth.assertThat;
import static com.google.common.truth.Truth.assert_;
import static google.registry.util.DiffUtils.prettyPrintDeepDiff;
import static java.nio.charset.StandardCharsets.UTF_8;
import static java.util.Arrays.asList;

import com.google.appengine.api.taskqueue.dev.QueueStateInfo;
import com.google.appengine.api.taskqueue.dev.QueueStateInfo.HeaderWrapper;
import com.google.appengine.api.taskqueue.dev.QueueStateInfo.TaskStateInfo;
import com.google.common.base.Function;
import com.google.common.base.Joiner;
import com.google.common.base.Predicate;
import com.google.common.collect.ArrayListMultimap;
import com.google.common.collect.FluentIterable;
import com.google.common.collect.ImmutableMultimap;
import com.google.common.collect.ImmutableMultiset;
import com.google.common.collect.Iterables;
import com.google.common.collect.Maps;
import com.google.common.collect.Multimap;
import com.google.common.net.HttpHeaders;
import com.google.common.net.MediaType;

import google.registry.dns.DnsConstants;

import org.joda.time.Duration;

import java.net.URI;
import java.util.Arrays;
import java.util.Collections;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Objects;

import javax.annotation.Nonnull;

/** Static utility functions for testing task queues. */
public class TaskQueueHelper {

  /**
   * Matcher to match against the tasks in the task queue. Fields that aren't set are not compared.
   */
  public static class TaskMatcher implements Predicate<TaskStateInfo> {

    MatchableTaskInfo expected = new MatchableTaskInfo();

    public TaskMatcher taskName(String taskName) {
      expected.taskName = taskName;
      return this;
    }

    public TaskMatcher url(String url) {
      expected.url = url;
      return this;
    }

    public TaskMatcher method(String method) {
      expected.method = method;
      return this;
    }

    public TaskMatcher payload(String payload) {
      checkState(
          expected.params.isEmpty(), "Cannot add a payload to a TaskMatcher with params.");
      expected.payload = payload;
      return this;
    }

    public TaskMatcher tag(String tag) {
      expected.tag = tag;
      return this;
    }

    public TaskMatcher header(String name, String value) {
      // Lowercase for case-insensitive comparison.
      expected.headers.put(name.toLowerCase(), value);
      return this;
    }

    public TaskMatcher param(String key, String value) {
      checkState(
          expected.payload == null, "Cannot add params to a TaskMatcher with a payload.");
      expected.params.put(key, value);
      return this;
    }

    public TaskMatcher etaDelta(Duration lowerBound, Duration upperBound) {
      checkState(!lowerBound.isShorterThan(Duration.ZERO), "lowerBound must be non-negative.");
      checkState(
          upperBound.isLongerThan(lowerBound), "upperBound must be greater than lowerBound.");
      expected.etaDeltaLowerBound = lowerBound.getStandardSeconds();
      expected.etaDeltaUpperBound = upperBound.getStandardSeconds();
      return this;
    }

    /**
     * Returns {@code true} if there are not more occurrences in {@code sub} of each of its entries
     * than there are in {@code super}.
     */
    private static boolean containsEntries(
        Multimap<?, ?> superMultimap, Multimap<?, ?> subMultimap) {
      return containsOccurrences(
          ImmutableMultiset.copyOf(superMultimap.entries()),
          ImmutableMultiset.copyOf(subMultimap.entries()));
    }

    /**
     * Returns true if the fields set on the current object match the given task info. This is not
     * quite the same contract as {@link #equals}, since it will ignore null fields.
     *
     * <p>Match fails if any headers or params expected on the TaskMatcher are not found on the
     * TaskStateInfo. Note that the inverse is not true (i.e. there may be extra headers on the
     * TaskStateInfo).
     */
    @Override
    public boolean apply(@Nonnull TaskStateInfo info) {
      MatchableTaskInfo actual = new MatchableTaskInfo(info);
      return (expected.taskName == null || Objects.equals(expected.taskName, actual.taskName))
          && (expected.url == null || Objects.equals(expected.url, actual.url))
          && (expected.method == null || Objects.equals(expected.method, actual.method))
          && (expected.payload == null || Objects.equals(expected.payload, actual.payload))
          && (expected.tag == null || Objects.equals(expected.tag, actual.tag))
          && (expected.etaDeltaLowerBound == null
              || expected.etaDeltaLowerBound <= actual.etaDelta)
          && (expected.etaDeltaUpperBound == null
              || expected.etaDeltaUpperBound >= actual.etaDelta)
          && containsEntries(actual.params, expected.params)
          && containsEntries(actual.headers, expected.headers);
    }

    @Override
    public String toString() {
      return Joiner.on('\n')
          .withKeyValueSeparator(":\n")
          .join(
              Maps.transformValues(
                  expected.toMap(),
                  new Function<Object, String>() {
                    @Override
                    public String apply(Object input) {
                      return "\t" + String.valueOf(input).replaceAll("\n", "\n\t");
                    }
                  }));
    }
  }

  /** Returns the info object for the provided queue name. */
  public static QueueStateInfo getQueueInfo(String queueName) {
    return getLocalTaskQueue().getQueueStateInfo().get(queueName);
  }

  /**
   * Ensures that the tasks in the named queue are exactly those with the expected property
   * values after being transformed with the provided property getter function.
   */
  public static void assertTasksEnqueuedWithProperty(
      String queueName,
      Function<TaskStateInfo, String> propertyGetter,
      String... expectedTaskProperties) throws Exception {
    // Ordering is irrelevant but duplicates should be considered independently.
    assertThat(transform(getQueueInfo(queueName).getTaskInfo(), propertyGetter))
        .containsExactly((Object[]) expectedTaskProperties);
  }

  /** Ensures that the tasks in the named queue are exactly those with the expected names. */
  public static void assertTasksEnqueued(String queueName, String... expectedTaskNames)
      throws Exception {
    Function<TaskStateInfo, String> nameGetter = new Function<TaskStateInfo, String>() {
      @Nonnull
      @Override
      public String apply(@Nonnull TaskStateInfo taskStateInfo) {
        return taskStateInfo.getTaskName();
      }};
    assertTasksEnqueuedWithProperty(queueName, nameGetter, expectedTaskNames);
  }

  /**
   * Ensures that the only tasks in the named queue are exactly those that match the expected
   * matchers.
   */
  public static void assertTasksEnqueued(String queueName, TaskMatcher... taskMatchers)
      throws Exception {
    assertTasksEnqueued(queueName, Arrays.asList(taskMatchers));
  }

  /**
   * Ensures that the only tasks in the named queue are exactly those that match the expected
   * matchers.
   */
  public static void assertTasksEnqueued(String queueName, List<TaskMatcher> taskMatchers)
      throws Exception {
    QueueStateInfo qsi = getQueueInfo(queueName);
    assertThat(qsi.getTaskInfo()).hasSize(taskMatchers.size());
    LinkedList<TaskStateInfo> taskInfos = new LinkedList<>(qsi.getTaskInfo());
    for (final TaskMatcher taskMatcher : taskMatchers) {
      try {
        taskInfos.remove(Iterables.find(taskInfos, taskMatcher));
      } catch (NoSuchElementException e) {
        final Map<String, Object> taskMatcherMap = taskMatcher.expected.toMap();
        assert_().fail(
            "Task not found in queue %s:\n\n%s\n\nPotential candidate match diffs:\n\n%s",
            queueName,
            taskMatcher,
            FluentIterable.from(taskInfos)
                .transform(new Function<TaskStateInfo, String>() {
                    @Override
                    public String apply(TaskStateInfo input) {
                      return prettyPrintDeepDiff(
                          taskMatcherMap,
                          Maps.filterKeys(
                              new MatchableTaskInfo(input).toMap(),
                              in(taskMatcherMap.keySet())));
                    }})
                .join(Joiner.on('\n')));
      }
    }
  }

  /** Empties the task queue. */
  public static void clearTaskQueue(String queueName) throws Exception {
    getLocalTaskQueue().flushQueue(queueName);
  }

  /** Asserts at least one task exists in {@code queue}. */
  public static void assertAtLeastOneTaskIsEnqueued(String queue) throws Exception {
    assertThat(getQueueInfo(queue).getCountTasks()).isGreaterThan(0);
  }

  /** Ensures that the named queue contains no tasks. */
  public static void assertNoTasksEnqueued(String queueName) throws Exception {
    assertThat(getQueueInfo(queueName).getCountTasks()).isEqualTo(0);
  }

  /** Returns the value for the param on a task info, or empty if it is missing. */
  private static String getParamFromTaskInfo(TaskStateInfo taskInfo, String paramName) {
    return getFirst(UriParameters.parse(taskInfo.getBody()).get(paramName), "");
  }

  /** Ensures that the DNS queue tasks are exactly those for the expected target names. */
  public static void assertDnsTasksEnqueued(String... expectedTaskTargetNames) throws Exception {
    assertTasksEnqueuedWithProperty(
        DnsConstants.DNS_PULL_QUEUE_NAME,
        new Function<TaskStateInfo, String>() {
          @Nonnull
          @Override
          public String apply(@Nonnull TaskStateInfo taskStateInfo) {
            return getParamFromTaskInfo(taskStateInfo, DnsConstants.DNS_TARGET_NAME_PARAM);
          }},
        expectedTaskTargetNames);
  }

  /** Ensures that the DNS queue does not contain any tasks. */
  public static void assertNoDnsTasksEnqueued() throws Exception {
    assertNoTasksEnqueued(DnsConstants.DNS_PULL_QUEUE_NAME);
  }

  /** An adapter to clean up a {@link TaskStateInfo} for ease of matching. */
  private static class MatchableTaskInfo {

    String taskName;
    String method;
    String url;
    String payload;
    String tag;
    Double etaDelta;
    Long etaDeltaLowerBound;
    Long etaDeltaUpperBound;
    Multimap<String, String> headers = ArrayListMultimap.create();
    Multimap<String, String> params = ArrayListMultimap.create();

    MatchableTaskInfo() {}

    MatchableTaskInfo(TaskStateInfo info) {
      URI uri;
      try {
        uri = new URI(info.getUrl());
      } catch (java.net.URISyntaxException e) {
        throw new IllegalArgumentException(e);
      }
      this.taskName = info.getTaskName();
      this.method = info.getMethod();
      this.url = uri.getPath();
      this.payload = info.getBody();
      this.etaDelta = info.getEtaDelta();
      if (info.getTagAsBytes() != null) {
        this.tag = new String(info.getTagAsBytes(), UTF_8);
      }
      ImmutableMultimap.Builder<String, String> headerBuilder = ImmutableMultimap.builder();
      for (HeaderWrapper header : info.getHeaders()) {
        // Lowercase header name for comparison since HTTP
        // header names are case-insensitive.
        headerBuilder.put(header.getKey().toLowerCase(), header.getValue());
      }
      this.headers = headerBuilder.build();
      ImmutableMultimap.Builder<String, String> inputParams = new ImmutableMultimap.Builder<>();
      String query = uri.getQuery();
      if (query != null) {
        inputParams.putAll(UriParameters.parse(query));
      }
      if (headers.containsEntry(
          HttpHeaders.CONTENT_TYPE.toLowerCase(), MediaType.FORM_DATA.toString())) {
        inputParams.putAll(UriParameters.parse(info.getBody()));
      }
      this.params = inputParams.build();
    }

    public Map<String, Object> toMap() {
      Map<String, Object> builder = new HashMap<>();
      builder.put("taskName", taskName);
      builder.put("url", url);
      builder.put("method", method);
      builder.put("headers", headers.asMap());
      builder.put("params", params.asMap());
      builder.put("payload", payload);
      builder.put("tag", tag);
      builder.put("etaDelta", etaDelta);
      builder.put("etaDeltaLowerBound", etaDeltaLowerBound);
      builder.put("etaDeltaUpperBound", etaDeltaUpperBound);
      return Maps.filterValues(builder, not(in(asList(null, "", Collections.EMPTY_MAP))));
    }
  }
}