org.apache.solr.client.solrj.impl.SolrHttpRequestRetryHandler.java Source code

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Here is the source code for org.apache.solr.client.solrj.impl.SolrHttpRequestRetryHandler.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.apache.solr.client.solrj.impl;

import java.io.IOException;
import java.io.InterruptedIOException;
import java.lang.invoke.MethodHandles;
import java.net.ConnectException;
import java.net.UnknownHostException;
import java.util.Arrays;
import java.util.Collection;
import java.util.HashSet;
import java.util.Set;

import javax.net.ssl.SSLException;

import org.apache.http.HttpRequest;
import org.apache.http.client.HttpRequestRetryHandler;
import org.apache.http.client.methods.HttpUriRequest;
import org.apache.http.client.protocol.HttpClientContext;
import org.apache.http.impl.client.RequestWrapper;
import org.apache.http.protocol.HttpContext;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

public class SolrHttpRequestRetryHandler implements HttpRequestRetryHandler {

    private static final String GET = "GET";

    private static final Logger log = LoggerFactory.getLogger(MethodHandles.lookup().lookupClass());

    public static final SolrHttpRequestRetryHandler INSTANCE = new SolrHttpRequestRetryHandler();

    /** the number of times a method will be retried */
    private final int retryCount;

    private final Set<Class<? extends IOException>> nonRetriableClasses;

    /**
     * Create the request retry handler using the specified IOException classes
     *
     * @param retryCount
     *          how many times to retry; 0 means no retries
     *          true if it's OK to retry requests that have been sent
     * @param clazzes
     *          the IOException types that should not be retried
     */
    protected SolrHttpRequestRetryHandler(final int retryCount,
            final Collection<Class<? extends IOException>> clazzes) {
        super();
        this.retryCount = retryCount;
        this.nonRetriableClasses = new HashSet<Class<? extends IOException>>();
        for (final Class<? extends IOException> clazz : clazzes) {
            this.nonRetriableClasses.add(clazz);
        }
    }

    /**
     * Create the request retry handler using the following list of non-retriable IOException classes: <br>
     * <ul>
     * <li>InterruptedIOException</li>
     * <li>UnknownHostException</li>
     * <li>ConnectException</li>
     * <li>SSLException</li>
     * </ul>
     * 
     * @param retryCount
     *          how many times to retry; 0 means no retries
     *          true if it's OK to retry non-idempotent requests that have been sent
     */
    @SuppressWarnings("unchecked")
    public SolrHttpRequestRetryHandler(final int retryCount) {
        this(retryCount, Arrays.asList(InterruptedIOException.class, UnknownHostException.class,
                ConnectException.class, SSLException.class));
    }

    /**
     * Create the request retry handler with a retry count of 3, requestSentRetryEnabled false and using the following
     * list of non-retriable IOException classes: <br>
     * <ul>
     * <li>InterruptedIOException</li>
     * <li>UnknownHostException</li>
     * <li>ConnectException</li>
     * <li>SSLException</li>
     * </ul>
     */
    public SolrHttpRequestRetryHandler() {
        this(3);
    }

    @Override
    public boolean retryRequest(final IOException exception, final int executionCount, final HttpContext context) {
        log.debug("Retry http request {} out of {}", executionCount, this.retryCount);
        if (executionCount > this.retryCount) {
            log.debug("Do not retry, over max retry count");
            return false;
        }
        if (this.nonRetriableClasses.contains(exception.getClass())) {
            log.debug("Do not retry, non retriable class {}", exception.getClass().getName());
            return false;
        } else {
            for (final Class<? extends IOException> rejectException : this.nonRetriableClasses) {
                if (rejectException.isInstance(exception)) {
                    log.debug("Do not retry, non retriable class {}", exception.getClass().getName());
                    return false;
                }
            }
        }
        final HttpClientContext clientContext = HttpClientContext.adapt(context);
        final HttpRequest request = clientContext.getRequest();

        if (requestIsAborted(request)) {
            log.debug("Do not retry, request was aborted");
            return false;
        }

        if (handleAsIdempotent(clientContext)) {
            log.debug("Retry, request should be idempotent");
            return true;
        }

        log.debug("Do not retry, no allow rules matched");
        return false;
    }

    public int getRetryCount() {
        return retryCount;
    }

    protected boolean handleAsIdempotent(final HttpClientContext context) {
        String method = context.getRequest().getRequestLine().getMethod();
        // do not retry admin requests, even if they are GET as they are not idempotent
        if (context.getRequest().getRequestLine().getUri().startsWith("/admin/")) {
            log.debug("Do not retry, this is an admin request");
            return false;
        }
        return method.equals(GET);
    }

    protected boolean requestIsAborted(final HttpRequest request) {
        HttpRequest req = request;
        if (request instanceof RequestWrapper) { // does not forward request to original
            req = ((RequestWrapper) request).getOriginal();
        }
        return (req instanceof HttpUriRequest && ((HttpUriRequest) req).isAborted());
    }

}