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javaapache-httpclient-4.xspring-ws

Ignore DNS Round-Robin for a Reliable Timeout with Spring-ws and 4.5.x Http Client

We are using Http Client 4.5.x with Spring-Ws and make requests with the webServiceTemplate.marshalSendAndReceive(requestObject) method. We would like to have a reliable connection timeout value, but are currently running into the issue described here in section 8 (DNS round robin) where multiple ip addresses are tried and so the timeout is unpredictable. Are there simple ways to set up a hard time-out after a certain time using just the Spring-ws and Http Client library, or is setting up some sort of custom timeout necessary?

Case: Connection timeout set to 1 second (actual timeout for the method is 4 seconds -- is it possible to set a method timeout of 1 second using the Spring/Http client library?)

Application logs (Http Client logs set to DEBUG):

16:45:02 (org.apache.http.impl.execchain.MainClientExec) Opening connection {}->http://salesforce.com:448 
16:45:02 (org.apache.http.impl.conn.DefaultHttpClientConnectionOperator) Connecting to salesforce.com/96.43.149.26:448 
16:45:03 (org.apache.http.impl.conn.DefaultHttpClientConnectionOperator) Connect to salesforce.com/96.43.149.26:448 timed out. Connection will be retried using another IP address 
16:45:03 (org.apache.http.impl.conn.DefaultHttpClientConnectionOperator) Connecting to salesforce.com/96.43.145.26:448 
16:45:04 (org.apache.http.impl.conn.DefaultHttpClientConnectionOperator) Connect to salesforce.com/96.43.145.26:448 timed out. Connection will be retried using another IP address 
16:45:04 (org.apache.http.impl.conn.DefaultHttpClientConnectionOperator) Connecting to salesforce.com/96.43.144.26:448 
16:45:05 (org.apache.http.impl.conn.DefaultHttpClientConnectionOperator) Connect to salesforce.com/96.43.144.26:448 timed out. Connection will be retried using another IP address 
16:45:05 (org.apache.http.impl.conn.DefaultHttpClientConnectionOperator) Connecting to salesforce.com/96.43.148.26:448
16:45:06 (org.apache.http.impl.conn.DefaultManagedHttpClientConnection) http-outgoing-0: Shutdown connection

Http client bean:

<bean id="httpClientBean" class="org.apache.http.client.HttpClient" factory-bean="httpClientFactory" factory-method="getHttpClient" />

Http Factory code (connection timeout value set via Spring dependency injection):

public class HttpFactory {
    private int connectionTimeout;

    public HttpFactory(int connectionTimeout, ...) {
        this.connectionTimeout = connectionTimeout;
        ...
    }

    ...

    public HttpClient getHttpClient() {
        HttpClientBuilder clientBuilder = HttpClientBuilder.create();
        ...
        RequestConfig.Builder configBuilder = RequestConfig.custom();
        configBuilder.setConnectTimeout(this.connectionTimeout);
        clientBuilder.setDefaultRequestConfig(configBuilder.build());
        ...

        return clientBuilder.build();
    }
}

Web service template bean:

    <bean id="webServiceTemplate" class="org.springframework.ws.client.core.WebServiceTemplate">
        ...
        <property name="messageSender"> 
            <bean class="org.springframework.ws.transport.http.HttpComponentsMessageSender">
                <constructor-arg index="0">
                    <ref bean="httpClientBean" />
                </constructor-arg>
            </bean> 
        </property>
    </bean>

Service code (we want this method call to take X seconds, not 2x or 3x seconds): 

// we want this method call to take ~1 second, not ~4 seconds (i.e. similar to the connection timeout value, not a multiplier)
Object obj = webServiceTemplate.marshalSendAndReceive(requestDocument);
Solution

  • There are two options

    1. Building a custom ClientConnectionOperator

    2. Building a custom DnsResolver. This option is much simpler.

      CloseableHttpClient client = HttpClients.custom()
   .setDnsResolver(host -> new InetAddress[] { InetAddress.getByName(host) })
   .build();