具有多个http出站网关的Spring Integration不会清除标头

Question

In a situation where I have:

<int-http:outbound-gateway request-channel="dataHubRawDataUploadChannel"
        id="raw" url-expression="headers['rawUrl']" http-method="POST"
        extract-request-payload="true" header-mapper="headerMapper"
        reply-channel="rawDataUploadResponseChannel" expected-response-type="java.lang.String" 
         error-handler="rawResponseErrorHandler" />

    <int-http:outbound-gateway request-channel="canonicalHttpChannel"
        id="canonical" url-expression="headers['canonicalUrl']"
        http-method="POST" header-mapper="headerMapper" reply-channel="targetDataUploadChannel"
        expected-response-type="java.lang.String"    rest-template="customRestTemplate"/>


    <int-http:outbound-gateway request-channel="targetHttpChannel"
        id="target" url-expression="headers['targetUrl']"
        http-method="POST" header-mapper="headerMapper" reply-channel="targetUploadResponseProcessor"
        expected-response-type="java.lang.String" />

I face the following problem:

The headers of the first and second request are not cleared when sending the third request , resulting in a Http 400 response.

I tried to clean the headers but the only solution I found is to override the RestTemplate class responsible for the actual HTTP request and clear the headers there, which is an ugly solution.

Do you have a better way to do it with Spring Integration?

Answer 1

The DefaultHttpHeaderMapper has a method setExcludedOutboundStandardRequestHeaderNames where you can pass it an array of header names that you don't want propagated from the outbound message.

See this answer for an example.

EDIT

If you are using Java configuration, simply define that mapper as a @Bean as shown in that answer.

If you are using XML configuration:

<bean id="mapper" class="org.springframework.integration.http.support.DefaultHttpHeaderMapper"
        factory-method="outboundMapper">
    <property name="excludedInboundStandardResponseHeaderNames">
        <array>
            <value>Host</value>
            <value>User-Agent</value>
        </array>
    </property>
</bean>