no suitable HttpMessageConverter found for request type [request.model.RTPRequest] and content type [application/x-java-serialized-object]

Question

I am trying to invoke a POST method on a REST service using Spring Integration's HttpRequestExecutingMessageHandler.

I have already tried the solution provided on the Could not write request: no suitable HttpMessageConverter found for request type and content type [application/x-java-serialized-object]

Below is my configuration: I have @EnableIntegration and @IntegrationComponentScan annotations on the bean configuration class. I have verified that I have Jackson data-bind jar on the classpath. I am able to get a valid response using POSTMAN.

@Bean
public MessageChannel rtpRequestChannel() {
    MessageChannel rtpRequestPostOperationRequestChannel = new DirectChannel();
    return rtpRequestPostOperationRequestChannel;
}

@Bean
public MessageChannel rtpResponseChannel() {
    MessageChannel rtpRequestPostOperationResponseChannel = new DirectChannel();
    return rtpRequestPostOperationResponseChannel;
}

@ServiceActivator(inputChannel = "rtpRequestChannel")
@Bean
public MessageHandler httResponseMessageHandler(MessageChannel rtpResponseChannel) {

    HttpRequestExecutingMessageHandler handler = new HttpRequestExecutingMessageHandler(
            "http://myhost:8080/services/v1-0/request");
    handler.setHttpMethod(HttpMethod.POST);
    handler.setOutputChannel(rtpResponseChannel);
    handler.setExpectedResponseType(RTPResponse.class);
    return handler;
}

Below is the POJO for service activator endpoint.

@Service
public class RTPRequestServiceClient implements IRTPRequestServiceClient {

    @Override
    @ServiceActivator(inputChannel="rtpRequestChannel")
    public void makeCall(Message<RtpResponse> pr) {
        RtpResponse response = pr.getPayload();
        System.out.println(response);
    }

My request POJO is:

public class RTPRequest implements Serializable {

    private static final long serialVersionUID = 567078627620810886L;

    private final String id;
    private final String paymentAmountCcy;
    private final String paymentAmount;

    @JsonCreator
    public RTPRequest(@JsonProperty("id") String id,
            @JsonProperty("paymentAmountCcy") String paymentAmountCcy,
            @JsonProperty("paymentAmount") String paymentAmount) {
        this.id = id;
        this.paymentAmountCcy = paymentAmountCcy;
        this.paymentAmount = paymentAmount;
    }

    // getters ommited for brevity

}

My responsePOJO is:

public class RTPResponse implements Serializable {

    /**
     * 
     */
    private static final long serialVersionUID = -3504586520124861349L;

    private String id;
    private String responseId;

    @JsonCreator
    public RTPResponse(@JsonProperty("id") String id, @JsonProperty("responseId") String responseId) {
        super();
        this.id = id;
        this.responseId = responseId;
    }

    // getters ommited for brevity

}

I am sending the request as follows:

RTPRequest body = new RTPRequest(....);

AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext(IntegrationBeanConfiguration.class);
        MessageChannel rtpRequestChannel = (MessageChannel) context.getBean("rtpRequestChannel");
        rtpRequestChannel
        .send(
                MessageBuilder.withPayload(body)
                .setHeader("accept","application/json")
                .setHeader("Sender","API_GATEWAY")
                .setHeader("ClientId","DIGITAL")
                .build()
            );

I am fairly new to Spring integration http. I was assuming that RTPRequest object will be converted into JSON by the virtue of HttpRequestExecutingMessageHandler default message converter chain and Jackson data-bind in classpath.

Please advise.

Answer 1

When you send your request, you have to explicitly set contentType header alongside with that accept:

.setHeader(MessageHeaders.CONTENT_TYPE,"application/json")

To enforce RestTemplate to use the mentioned MappingJackson2HttpMessageConverter.

Or you can configure HttpRequestExecutingMessageHandler only use this MappingJackson2HttpMessageConverter.