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.
   */
  package org.apache.beam.sdk.extensions.gcp.util;
  
  import com.google.auto.value.AutoValue;
  import java.io.Serializable;
  import java.util.ArrayList;
  import java.util.List;
  
  /**
   * An optional component to use with the {@code RetryHttpRequestInitializer} in order to provide
   * custom errors for failing http calls. This class allows you to specify custom error messages
   * which match specific error codes and containing strings in the URL. The first matcher to match
   * the request and response will be used to provide the custom error.
   *
   * <p>The intended use case here is to examine one of the logs emitted by a failing call made by the
   * RetryHttpRequestInitializer, and then adding a custom error message which matches the URL and
   * code for it.
   *
   * <p>Usage: See more in CustomHttpErrorsTest.
   *
   * <pre>{@code
   * CustomHttpErrors.Builder builder = new CustomHttpErrors.Builder();
   * builder.addErrorForCodeAndUrlContains(403,"/tables?", "Custom Error Msg");
   * CustomHttpErrors customErrors = builder.build();
   *
   *
   * RetryHttpRequestInitializer initializer = ...
   * initializer.setCustomErrors(customErrors);
   * }</pre>
   *
   * <p>Suggestions for future enhancements to anyone upgrading this file:
   *
   * <ul>
   *   <li>This class is left open for extension, to allow different functions for HttpCallMatcher and
   *       HttpCallCustomError to match and log errors. For example, new functionality may include
   *       matching an error based on the HttpResponse body. Additionally, extracting and logging
   *       strings from the HttpResponse body may make useful functionality.
   *   <li>Add a methods to add custom errors based on inspecting the contents of the HttpRequest and
   *       HttpResponse
   *   <li>Be sure to update the HttpRequestWrapper and HttpResponseWrapper with any new getters that
   *       you may use. The wrappers were introduced to add a layer of indirection which could be
   *       mocked mocked out in tests. This was unfortunately needed because mockito cannot mock final
   *       classes and its non trivial to just construct HttpRequest and HttpResponse objects.
   *   <li>Making matchers composable with an AND operator may simplify enhancing this code, if
   *       several different matchers are used.
   * </ul>
   *
   * <p>
   */
  @SuppressWarnings({
    "nullness" // TODO(https://github.com/apache/beam/issues/20497)
  })
  public class CustomHttpErrors {
  
    /**
     * A simple Tuple class for creating a list of HttpResponseMatcher and HttpResponseCustomError to
     * print for the responses.
     */
    @AutoValue
    public abstract static class MatcherAndError implements Serializable {
      static MatcherAndError create(HttpCallMatcher matcher, HttpCallCustomError customError) {
        return new AutoValue_CustomHttpErrors_MatcherAndError(matcher, customError);
      }
  
      public abstract HttpCallMatcher getMatcher();
  
      public abstract HttpCallCustomError getCustomError();
    }
  
    /** A Builder which allows building immutable CustomHttpErrors object. */
    public static class Builder {
  
      private List<MatcherAndError> matchersAndLogs = new ArrayList<MatcherAndError>();
  
      public CustomHttpErrors build() {
        return new CustomHttpErrors(this.matchersAndLogs);
      }
  
      /** Adds a matcher to log the provided string if the error matches a particular status code. */
      public void addErrorForCode(int statusCode, String errorMessage) {
        HttpCallMatcher matcher = (req, resp) -> resp.getStatusCode() == statusCode;
        this.matchersAndLogs.add(MatcherAndError.create(matcher, simpleErrorMessage(errorMessage)));
      }
  
      /**
       * Adds a matcher to log the provided string if the error matches a particular status code and
       * the url contains a certain string.
       */
      public void addErrorForCodeAndUrlContains(
          int statusCode, String urlContains, String errorMessage) {
        HttpCallMatcher matcher =
            (request, response) -> {
              if (response.getStatusCode() == statusCode
                  && request.getUrl().toString().contains(urlContains)) {
                return true;
              }
              return false;
            };
        this.matchersAndLogs.add(MatcherAndError.create(matcher, simpleErrorMessage(errorMessage)));
      }
  
      private static HttpCallCustomError simpleErrorMessage(String errorMessage) {
        return (request, response) -> {
          return errorMessage;
        };
      }
    }
  
    // The list of HttpRequest/Response matchers and functions to generate error strings.
    private List<MatcherAndError> matchersAndLogs = new ArrayList<MatcherAndError>();
  
    private CustomHttpErrors(List<MatcherAndError> matchersAndLogs) {
      // Deep copy the matchersAndLogs, which allows the builder to be reused.
      for (MatcherAndError m : matchersAndLogs) {
        this.matchersAndLogs.add(m);
      }
    }
  
    /** @return The first custom error for the failing request and response to match, or null. */
    public String getCustomError(HttpRequestWrapper req, HttpResponseWrapper res) {
      for (MatcherAndError m : matchersAndLogs) {
        if (m.getMatcher().matchResponse(req, res)) {
          return m.getCustomError().customError(req, res);
        }
      }
      return null;
    }
  }
  