apache-camelactivemq-classicalfrescojbossfusecamel-http

Send data to an external resource: why content is null?


I have a simple Camel route. I want to extract a file from the queue and pass it by using POST request to an external resource. This route works and the request reaches an external resource:

import org.apache.camel.Exchange;
import org.apache.camel.Processor;
import org.apache.camel.builder.RouteBuilder;

public class MyRouteBuilder extends RouteBuilder {

    @Override
    public void configure() throws Exception {
        from("activemq:alfresco-queue")
        .process(new Processor() {
            public void process(Exchange exchange) throws Exception {
                byte[] bytes = exchange.getIn().getBody(byte[].class);

                // All of that not working...
                // exchange.getIn().setHeader("content", bytes); gives "java.lang.IllegalAgrumentException: Request header is too large"
                // exchange.getIn().setBody(bytes, byte[].class); gives "size of content is -1"
                // exchange.getIn().setBody(bytes); gives "size of content is -1"
                // ???

                // ??? But I can print file content here
                for(int i=0; i < bytes.length; i++) {
                    System.out.print((char) bytes[i]);
                }
            }
        })

        .setHeader(Exchange.HTTP_METHOD, constant("POST"))
        .setHeader(Exchange.CONTENT_TYPE, constant("multipart/form-data"))
        .to("http://vm-alfce52-31......com:8080/alfresco/s/someco/queuefileuploader?guest=true")

        .process(new Processor() {
            public void process(Exchange exchange) throws Exception {
                System.out.println("The response code is: " + exchange.getIn().getHeader(Exchange.HTTP_RESPONSE_CODE));
            }
        });
    }
}

The question is that the payload of the request is lost:

// somewhere on an external resource
Content content = request.getContent();
long len = content.getSize() // is always == -1.

// the file name is passed successfully
String fileName = request.getHeader("fileName");

How to set and pass the payload of POST request in this route/ processor?

I noticed that ANY data setted by this way is losted too. Only the headers are sent to the remote resource.

By using simple HTML form with <input type="file"> encoded in multipart/form-data I can successfully send all the data to the external resource.

What could be the reason?


Updated.

The following code also gives null-content:

MultipartEntityBuilder multipartEntityBuilder = MultipartEntityBuilder.create();
multipartEntityBuilder.setMode(HttpMultipartMode.BROWSER_COMPATIBLE);

// this also gives null-content
//multipartEntityBuilder.addBinaryBody("file", exchange.getIn().getBody(byte[].class));

multipartEntityBuilder.addPart("file", new ByteArrayBody(exchange.getIn().getBody(byte[].class), exchange.getIn().getHeader("fileName", String.class)));
exchange.getOut().setBody(multipartEntityBuilder.build().getContent());

/********** This also gives null-content *********/
StringBody username = new StringBody("username", ContentType.MULTIPART_FORM_DATA); 
StringBody password = new StringBody("password", ContentType.MULTIPART_FORM_DATA); 

MultipartEntityBuilder multipartEntityBuilder = MultipartEntityBuilder.create(); 
multipartEntityBuilder.setMode(HttpMultipartMode.BROWSER_COMPATIBLE); 
multipartEntityBuilder.addPart("username", username); 
multipartEntityBuilder.addPart("password", password); 

String filename = (String) exchange.getIn().getHeader("fileName");

File file = new File(filename);
try(RandomAccessFile accessFile = new RandomAccessFile(file, "rw")) {
    accessFile.write(bytes);
}

multipartEntityBuilder.addPart("upload", new FileBody(file, ContentType.MULTIPART_FORM_DATA, filename));
exchange.getIn().setBody(multipartEntityBuilder.build().getContent());

One more detail. If I change this:

exchange.getOut().setBody(multipartEntityBuilder.build().getContent());

To this:

exchange.getOut().setBody(multipartEntityBuilder.build());

I get the following exception on FUSE side (I see it through hawtio management console):

Execution of JMS message listener failed.
Caused by: [org.apache.camel.RuntimeCamelException - org.apache.camel.InvalidPayloadException: 
No body available of type: java.io.InputStream but has value: org.apache.http.entity.mime.MultipartFormEntity@26ee73 of type: 
org.apache.http.entity.mime.MultipartFormEntity on: JmsMessage@0x1cb83b9. 
Caused by: No type converter available to convert from type: org.apache.http.entity.mime.MultipartFormEntity to the required type: 
java.io.InputStream with value org.apache.http.entity.mime.MultipartFormEntity@26ee73. Exchange[ID-63-DP-TAV-55652-1531889677177-5-1]. Caused by: 
[org.apache.camel.NoTypeConversionAvailableException - No type converter available to convert from type: 
org.apache.http.entity.mime.MultipartFormEntity to the required type: java.io.InputStream with value org.apache.http.entity.mime.MultipartFormEntity@26ee73]]

Solution

  • I write a small servlet application and get the content in the doPost(...) method from the HttpServletRequest object.

    The problem was with the WebScriptRequest object on the external system (Alfresco) side.

    @Bedla, thanks for your advices!


    On the Alfresco side the problem can be solved as follows:

    public class QueueFileUploader extends DeclarativeWebScript {
        protected Map<String, Object> executeImpl(WebScriptRequest req, Status status) {
            HttpServletRequest httpServletRequest = WebScriptServletRuntime.getHttpServletRequest(req);
            //  calling methods of httpServletRequest object and retrieving the content
            ...
    

    The route:

    public class MyRouteBuilder extends RouteBuilder {
    
        @Override
        public void configure() throws Exception {
            from("activemq:alfresco-queue")
            .process(new Processor() {
                public void process(Exchange exchange) throws Exception {
                    MultipartEntityBuilder multipartEntityBuilder = MultipartEntityBuilder.create();
                    multipartEntityBuilder.setMode(HttpMultipartMode.BROWSER_COMPATIBLE);
                    multipartEntityBuilder.addPart("file", new ByteArrayBody(exchange.getIn().getBody(byte[].class), 
                            exchange.getIn().getHeader("fileName", String.class)));
                    exchange.getIn().setBody(multipartEntityBuilder.build().getContent());              
                }
            })
    
            .setHeader(Exchange.HTTP_METHOD, constant(org.apache.camel.component.http4.HttpMethods.POST))
            .to("http4://localhost:8080/alfresco/s/someco/queuefileuploader?guest=true")
    //      .to("http4://localhost:8080/ServletApp/hello")
    
            .process(new Processor() {
                public void process(Exchange exchange) throws Exception {
                    System.out.println("The response code is: " + 
                            exchange.getIn().getHeader(Exchange.HTTP_RESPONSE_CODE));
                }
            });
        }
    }