This version is still in development and is not considered stable yet. For the latest stable version, please use Spring Integration 6.2.4!

HTTP Samples

This section wraps up our coverage of Spring Integration’s HTTP support with a few examples.

Multipart HTTP Request — RestTemplate (Client) and Http Inbound Gateway (Server)

This example shows how simple it is to send a multipart HTTP request with Spring’s RestTemplate and receive it with a Spring Integration HTTP inbound adapter. We create a MultiValueMap and populate it with multipart data. The RestTemplate takes care of the rest (no pun intended) by converting it to a MultipartHttpServletRequest. This particular client sends a multipart HTTP Request that contains the name of the company and an image file (the company logo). The following listing shows the example:

RestTemplate template = new RestTemplate();
String uri = "http://localhost:8080/multipart-http/inboundAdapter.htm";
Resource s2logo =
   new ClassPathResource("org/springframework/samples/multipart/spring09_logo.png");
MultiValueMap map = new LinkedMultiValueMap();
map.add("company", "SpringSource");
map.add("company-logo", s2logo);
HttpHeaders headers = new HttpHeaders();
headers.setContentType(new MediaType("multipart", "form-data"));
HttpEntity request = new HttpEntity(map, headers);
ResponseEntity<?> httpResponse = template.exchange(uri, HttpMethod.POST, request, null);

That is all we need for the client.

On the server side, we have the following configuration:

<int-http:inbound-channel-adapter id="httpInboundAdapter"
    channel="receiveChannel"
    path="/inboundAdapter.htm"
    supported-methods="GET, POST"/>

<int:channel id="receiveChannel"/>

<int:service-activator input-channel="receiveChannel">
    <bean class="org.springframework.integration.samples.multipart.MultipartReceiver"/>
</int:service-activator>

<bean id="multipartResolver"
    class="org.springframework.web.multipart.commons.CommonsMultipartResolver"/>

The 'httpInboundAdapter' receives the request and converts it to a Message with a payload that is a LinkedMultiValueMap. We then parse that in the 'multipartReceiver' service-activator, as the following example shows:

public void receive(LinkedMultiValueMap<String, Object> multipartRequest){
    System.out.println("### Successfully received multipart request ###");
    for (String elementName : multipartRequest.keySet()) {
        if (elementName.equals("company")){
            System.out.println("\t" + elementName + " - " +
                ((String[]) multipartRequest.getFirst("company"))[0]);
        }
        else if (elementName.equals("company-logo")){
            System.out.println("\t" + elementName + " - as UploadedMultipartFile: " +
                ((UploadedMultipartFile) multipartRequest
                    .getFirst("company-logo")).getOriginalFilename());
        }
    }
}

You should see the following output:

### Successfully received multipart request ###
   company - SpringSource
   company-logo - as UploadedMultipartFile: spring09_logo.png