Testing Binary File Upload on Jetty
I was developing a small web server using Jetty and Apache Commons FileUpload component when I faced the problem with automated testing of the upload functionality. Jetty has a very nice framework to do tests: ServletTester and HttpTester.
ServletTester tester = new ServletTester();
tester.setContextPath("/");
tester.addServlet(TestingHandler.class, "/");
tester.start();
HttpTester request = new HttpTester();
HttpTester response = new HttpTester();
request.setMethod("GET");
request.setURI("/");
response.parse(tester.getResponses(request.generate()));
assertEquals(200, response.getStatus());
My test had to upload a binary file to check the server-side processing, but I’ve found this is not an easy thing to do. I’ve realized that HttpTester class generate() method produces a String. Okay, let’s use BASE64 to encode the file! But this would not work, because FileUpload supports only «application/octet-stream» content type. Fortunately, FileUpload is an open source product, so I’ve just created a child class of HttpTester with my new generateBytes() method that did the trick. Basically, it is a slightly modified version of HttpTester.generate():
public static class HttpTesterBytes extends HttpTester {
public HttpTesterBytes() {
super();
setHeader("Host", "tester");
}
public ByteArrayBuffer generateBytes() throws IOException {
Buffer bb=new ByteArrayBuffer(32*1024 + (_genContent!=null?_genContent.length:0));
Buffer sb=new ByteArrayBuffer(4*1024);
ByteArrayOutputStream2 out = new ByteArrayOutputStream2();
StreamEndPoint endp = new StreamEndPoint(null, out);
HttpGenerator generator = new HttpGenerator(new SimpleBuffers(sb, bb),endp);
if (_method!=null) {
generator.setRequest(getMethod(),getURI());
if (_version==null)
generator.setVersion(HttpVersions.HTTP_1_1_ORDINAL);
else
generator.setVersion(HttpVersions.CACHE.getOrdinal(HttpVersions.CACHE.lookup(_version)));
generator.completeHeader(_fields,false);
if (_genContent!=null)
generator.addContent(new View(new ByteArrayBuffer(_genContent)),false);
else if (_parsedContent!=null)
generator.addContent(new ByteArrayBuffer(_parsedContent.toByteArray()),false);
}
generator.complete();
generator.flushBuffer();
return new ByteArrayBuffer(out.toByteArray());
}
}
To prepare the bytes I’ve made a helper function:
public final static String CONTENT_BOUNDARY = "<--(*)(*)-->"; // Spaceship!
/**
* Get the binary representation of the file upload
* @param fieldName field name to use in the form
* @param filename file to load
* @return bytes array with file written
* @throws IOException
*/
public static byte[] getFileRequestContent(String fieldName, String filename, boolean finalize) throws IOException {
String content = "--" + CONTENT_BOUNDARY + "\r\n" + "Content-Disposition: form-data; name=\"" + fieldName + "\"; filename=\"" + filename + "\"\r\n"+
"Content-Type: application/octet-stream;\r\n\r\n";
File f = new File(filename);
byte[] bytes = Files.toByteArray(f);
ByteArrayOutputStream stream = new ByteArrayOutputStream2();
stream.write(content.getBytes());
stream.write(bytes);
String finish = "\r\n";
if (finalize)
finish += "--" + CONTENT_BOUNDARY + "--\r\n\r\n";
stream.write(finish.getBytes());
stream.flush();
return stream.toByteArray();
}
And now how it looks in the test:
HttpTesterBytes request = new HttpTesterBytes();
HttpTester response = new HttpTester();
request.setMethod("POST");
request.setHeader("Content-Type", "multipart/form-data; boundary=" + CONTENT_BOUNDARY);
request.setContentBytes(getFileRequestContent("data_file, "test/Nocturne.jpg"));
response.parse(tester.getResponses(request.generateBytes()).array());
assertTrue(response.getMethod() == null);
assertEquals(200, response.getStatus());
assertTrue(response.getContent().contains("cute!"));