org.springframework.cloud.gateway.filter.WebClientWriteResponseFilter.java Source code

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Here is the source code for org.springframework.cloud.gateway.filter.WebClientWriteResponseFilter.java

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/*
 * Copyright 2013-2019 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
 *
 *      https://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.gateway.filter;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import reactor.core.publisher.Mono;

import org.springframework.core.Ordered;
import org.springframework.http.server.reactive.ServerHttpResponse;
import org.springframework.web.reactive.function.BodyExtractors;
import org.springframework.web.reactive.function.client.ClientResponse;
import org.springframework.web.server.ServerWebExchange;

import static org.springframework.cloud.gateway.support.ServerWebExchangeUtils.CLIENT_RESPONSE_ATTR;

/**
 * @author Spencer Gibb
 */
public class WebClientWriteResponseFilter implements GlobalFilter, Ordered {

    /**
     * Order of Write Response Filter.
     */
    public static final int WRITE_RESPONSE_FILTER_ORDER = -1;

    private static final Log log = LogFactory.getLog(WebClientWriteResponseFilter.class);

    @Override
    public int getOrder() {
        return WRITE_RESPONSE_FILTER_ORDER;
    }

    @Override
    public Mono<Void> filter(ServerWebExchange exchange, GatewayFilterChain chain) {
        // NOTICE: nothing in "pre" filter stage as CLIENT_RESPONSE_ATTR is not added
        // until the WebHandler is run
        return chain.filter(exchange).then(Mono.defer(() -> {
            ClientResponse clientResponse = exchange.getAttribute(CLIENT_RESPONSE_ATTR);
            if (clientResponse == null) {
                return Mono.empty();
            }
            log.trace("WebClientWriteResponseFilter start");
            ServerHttpResponse response = exchange.getResponse();

            return response.writeWith(clientResponse.body(BodyExtractors.toDataBuffers()))
                    .log("webClient response");
        }));
    }

}