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

Question

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]]

Answer 1

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));
}
});
}
}