org.springframework.cloud.netflix.ribbon.apache.RetryableRibbonLoadBalancingHttpClient.java Source code

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Here is the source code for org.springframework.cloud.netflix.ribbon.apache.RetryableRibbonLoadBalancingHttpClient.java

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/*
 * Copyright 2013-2017 the original author or authors.
 *
 * 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 org.springframework.cloud.netflix.ribbon.apache;

import java.io.IOException;
import java.net.URI;
import org.apache.commons.lang.BooleanUtils;
import org.apache.http.HttpResponse;
import org.apache.http.client.config.RequestConfig;
import org.apache.http.client.methods.HttpUriRequest;
import org.springframework.cloud.client.ServiceInstance;
import org.springframework.cloud.client.loadbalancer.LoadBalancedRetryContext;
import org.springframework.cloud.client.loadbalancer.LoadBalancedRetryPolicy;
import org.springframework.cloud.client.loadbalancer.LoadBalancedRetryPolicyFactory;
import org.springframework.cloud.client.loadbalancer.ServiceInstanceChooser;
import org.springframework.cloud.netflix.feign.ribbon.FeignRetryPolicy;
import org.springframework.cloud.netflix.ribbon.RibbonLoadBalancerClient;
import org.springframework.cloud.netflix.ribbon.ServerIntrospector;
import org.springframework.cloud.netflix.ribbon.support.RetryableStatusCodeException;
import org.springframework.http.HttpRequest;
import org.springframework.retry.RetryCallback;
import org.springframework.retry.RetryContext;
import org.springframework.retry.policy.NeverRetryPolicy;
import org.springframework.retry.support.RetryTemplate;
import org.springframework.web.util.UriComponentsBuilder;
import com.netflix.client.RequestSpecificRetryHandler;
import com.netflix.client.RetryHandler;
import com.netflix.client.config.CommonClientConfigKey;
import com.netflix.client.config.IClientConfig;
import com.netflix.loadbalancer.Server;

/**
 * An Apache HTTP client which leverages Spring Retry to retry failed requests.
 * @author Ryan Baxter
 */
public class RetryableRibbonLoadBalancingHttpClient extends RibbonLoadBalancingHttpClient
        implements ServiceInstanceChooser {
    private LoadBalancedRetryPolicyFactory loadBalancedRetryPolicyFactory = new LoadBalancedRetryPolicyFactory.NeverRetryFactory();

    public RetryableRibbonLoadBalancingHttpClient(IClientConfig config, ServerIntrospector serverIntrospector,
            LoadBalancedRetryPolicyFactory loadBalancedRetryPolicyFactory) {
        super(config, serverIntrospector);
        this.loadBalancedRetryPolicyFactory = loadBalancedRetryPolicyFactory;
    }

    @Override
    public RibbonApacheHttpResponse execute(final RibbonApacheHttpRequest request,
            final IClientConfig configOverride) throws Exception {
        final RequestConfig.Builder builder = RequestConfig.custom();
        IClientConfig config = configOverride != null ? configOverride : this.config;
        builder.setConnectTimeout(config.get(CommonClientConfigKey.ConnectTimeout, this.connectTimeout));
        builder.setSocketTimeout(config.get(CommonClientConfigKey.ReadTimeout, this.readTimeout));
        builder.setRedirectsEnabled(config.get(CommonClientConfigKey.FollowRedirects, this.followRedirects));

        final RequestConfig requestConfig = builder.build();
        final LoadBalancedRetryPolicy retryPolicy = loadBalancedRetryPolicyFactory.create(this.getClientName(),
                this);
        RetryCallback retryCallback = new RetryCallback() {
            @Override
            public RibbonApacheHttpResponse doWithRetry(RetryContext context) throws Exception {
                //on retries the policy will choose the server and set it in the context
                //extract the server and update the request being made
                RibbonApacheHttpRequest newRequest = request;
                if (context instanceof LoadBalancedRetryContext) {
                    ServiceInstance service = ((LoadBalancedRetryContext) context).getServiceInstance();
                    if (service != null) {
                        //Reconstruct the request URI using the host and port set in the retry context
                        newRequest = newRequest
                                .withNewUri(new URI(service.getUri().getScheme(), newRequest.getURI().getUserInfo(),
                                        service.getHost(), service.getPort(), newRequest.getURI().getPath(),
                                        newRequest.getURI().getQuery(), newRequest.getURI().getFragment()));
                    }
                }
                if (isSecure(configOverride)) {
                    final URI secureUri = UriComponentsBuilder.fromUri(newRequest.getUri()).scheme("https").build()
                            .toUri();
                    newRequest = newRequest.withNewUri(secureUri);
                }
                HttpUriRequest httpUriRequest = newRequest.toRequest(requestConfig);
                final HttpResponse httpResponse = RetryableRibbonLoadBalancingHttpClient.this.delegate
                        .execute(httpUriRequest);
                if (retryPolicy.retryableStatusCode(httpResponse.getStatusLine().getStatusCode())) {
                    throw new RetryableStatusCodeException(RetryableRibbonLoadBalancingHttpClient.this.clientName,
                            httpResponse.getStatusLine().getStatusCode());
                }
                return new RibbonApacheHttpResponse(httpResponse, httpUriRequest.getURI());
            }
        };
        return this.executeWithRetry(request, retryPolicy, retryCallback);
    }

    private RibbonApacheHttpResponse executeWithRetry(RibbonApacheHttpRequest request,
            LoadBalancedRetryPolicy retryPolicy, RetryCallback<RibbonApacheHttpResponse, IOException> callback)
            throws Exception {
        RetryTemplate retryTemplate = new RetryTemplate();
        boolean retryable = request.getContext() == null ? true
                : BooleanUtils.toBooleanDefaultIfNull(request.getContext().getRetryable(), true);
        retryTemplate.setRetryPolicy(retryPolicy == null || !retryable ? new NeverRetryPolicy()
                : new RetryPolicy(request, retryPolicy, this, this.getClientName()));
        return retryTemplate.execute(callback);
    }

    @Override
    public ServiceInstance choose(String serviceId) {
        Server server = this.getLoadBalancer().chooseServer(serviceId);
        return new RibbonLoadBalancerClient.RibbonServer(serviceId, server);
    }

    @Override
    public RequestSpecificRetryHandler getRequestSpecificRetryHandler(RibbonApacheHttpRequest request,
            IClientConfig requestConfig) {
        return new RequestSpecificRetryHandler(false, false, RetryHandler.DEFAULT, null);
    }

    static class RetryPolicy extends FeignRetryPolicy {
        public RetryPolicy(HttpRequest request, LoadBalancedRetryPolicy policy,
                ServiceInstanceChooser serviceInstanceChooser, String serviceName) {
            super(request, policy, serviceInstanceChooser, serviceName);
        }
    }
}