org.jclouds.rackspace.cloudidentity.v1_1.handlers.RetryOnRenew.java Source code

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Here is the source code for org.jclouds.rackspace.cloudidentity.v1_1.handlers.RetryOnRenew.java

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/*
 * 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.jclouds.rackspace.cloudidentity.v1_1.handlers;

import static org.jclouds.http.HttpUtils.closeClientButKeepContentStream;
import static org.jclouds.http.HttpUtils.releasePayload;

import java.util.concurrent.TimeUnit;

import javax.annotation.Resource;
import javax.inject.Named;

import org.jclouds.Constants;
import org.jclouds.domain.Credentials;
import org.jclouds.http.HttpCommand;
import org.jclouds.http.HttpResponse;
import org.jclouds.http.HttpRetryHandler;
import org.jclouds.http.handlers.BackoffLimitedRetryHandler;
import org.jclouds.logging.Logger;
import org.jclouds.rackspace.cloudidentity.v1_1.domain.Auth;

import com.google.common.annotations.VisibleForTesting;
import com.google.common.cache.Cache;
import com.google.common.cache.CacheBuilder;
import com.google.common.cache.LoadingCache;
import com.google.common.collect.Multimap;
import com.google.common.util.concurrent.Uninterruptibles;
import com.google.inject.Inject;
import com.google.inject.Singleton;

/**
 * This will parse and set an appropriate exception on the command object.
 */
@Singleton
public class RetryOnRenew implements HttpRetryHandler {
    @VisibleForTesting
    @Inject(optional = true)
    @Named(Constants.PROPERTY_MAX_RETRIES)
    static int NUM_RETRIES = 5;

    public final String AUTH_USER = "X-Auth-User";
    public final String AUTH_KEY = "X-Auth-Key";
    public final String AUTH_TOKEN = "X-Auth-Token";

    @Resource
    protected Logger logger = Logger.NULL;

    private final LoadingCache<Credentials, Auth> authenticationResponseCache;

    private final BackoffLimitedRetryHandler backoffHandler;

    @Inject
    protected RetryOnRenew(LoadingCache<Credentials, Auth> authenticationResponseCache,
            BackoffLimitedRetryHandler backoffHandler) {
        this.authenticationResponseCache = authenticationResponseCache;
        this.backoffHandler = backoffHandler;
    }

    /*
     * The reason retries need to be tracked is that it is possible that a token
     * can be expired at any time. The reason we track by request is that only
     * some requests might return a 401 (such as temporary URLs). However
     * consistent failures of the magnitude this code tracks should indicate a
     * problem.
     */
    private static final Cache<HttpCommand, Integer> retryCountMap = CacheBuilder.newBuilder()
            .expireAfterWrite(5, TimeUnit.MINUTES).build();

    @Override
    public boolean shouldRetryRequest(HttpCommand command, HttpResponse response) {
        boolean retry = false; // default
        try {
            switch (response.getStatusCode()) {
            case 401:
                // Do not retry on 401 from authentication request
                Multimap<String, String> headers = command.getCurrentRequest().getHeaders();
                if (headers != null && headers.containsKey(AUTH_USER) && headers.containsKey(AUTH_KEY)
                        && !headers.containsKey(AUTH_TOKEN)) {
                    retry = false;
                } else {
                    closeClientButKeepContentStream(response);
                    // This is not an authentication request returning 401
                    // Check if we already had seen this request
                    Integer count = retryCountMap.getIfPresent(command);

                    if (count == null) {
                        // First time this non-authentication request failed
                        logger.debug("invalidating authentication token - first time for %s", command);
                        retryCountMap.put(command, 1);
                        authenticationResponseCache.invalidateAll();
                        retry = true;
                    } else {
                        // This request has failed before
                        if (count + 1 >= NUM_RETRIES) {
                            logger.debug("too many 401s - giving up after: %s for %s", count, command);
                            retry = false;
                        } else {
                            // Retry just in case
                            logger.debug("invalidating authentication token - retry %s for %s", count, command);
                            retryCountMap.put(command, count + 1);
                            // Wait between retries
                            authenticationResponseCache.invalidateAll();
                            Uninterruptibles.sleepUninterruptibly(5, TimeUnit.SECONDS);
                            retry = true;
                        }
                    }
                }
                break;
            case 408:
                return backoffHandler.shouldRetryRequest(command, response);
            }
            return retry;

        } finally {
            releasePayload(response);
        }
    }

}