Multipart File Upload on Google Appengine using jersey-1.7

Question

I wrote an application on Google Appengine with Jersey to handle simple file uploading. This works fine when it was on jersey 1.2. In the later versions (current 1.7) @FormD

Answer 1

i've found solution to programmatically avoid to use temporary file creation (very useful for GAE implementation)

My solution consist of creating a new MultiPartReader Provider ... below my code

---

  @Provider
    @Consumes("multipart/*")
    public class GaeMultiPartReader implements MessageBodyReader {

    final Log logger = org.apache.commons.logging.LogFactory.getLog(getClass());

    private final Providers providers;

    private final CloseableService closeableService;

    private final MIMEConfig mimeConfig;

    private String getFixedHeaderValue(Header h) {
        String result = h.getValue();

        if (h.getName().equals("Content-Disposition") && (result.indexOf("filename=") != -1)) {
            try {
                result = new String(result.getBytes(), "utf8");
            } catch (UnsupportedEncodingException e) {            
                final String msg = "Can't convert header \"Content-Disposition\" to UTF8 format.";
                logger.error(msg,e);
                throw new RuntimeException(msg);
            }
        }

        return result;
    }

    public GaeMultiPartReader(@Context Providers providers, @Context MultiPartConfig config,
        @Context CloseableService closeableService) {
        this.providers = providers;

        if (config == null) {
            final String msg = "The MultiPartConfig instance we expected is not present. "
                + "Have you registered the MultiPartConfigProvider class?";
            logger.error( msg );
            throw new IllegalArgumentException(msg);
        }
        this.closeableService = closeableService;

        mimeConfig = new MIMEConfig();
        //mimeConfig.setMemoryThreshold(config.getBufferThreshold());
        mimeConfig.setMemoryThreshold(-1L); // GAE FIX
    }

    @Override
    public boolean isReadable(Class type, Type genericType, Annotation[] annotations, MediaType mediaType) {
        return MultiPart.class.isAssignableFrom(type);
    }

    @Override
    public MultiPart readFrom(Class type, Type genericType, Annotation[] annotations, MediaType mediaType,
        MultivaluedMap headers, InputStream stream) throws IOException, WebApplicationException {
        try {
            MIMEMessage mm = new MIMEMessage(stream, mediaType.getParameters().get("boundary"), mimeConfig);

            boolean formData = false;
            MultiPart multiPart = null;

            if (MediaTypes.typeEquals(mediaType, MediaType.MULTIPART_FORM_DATA_TYPE)) {
                multiPart = new FormDataMultiPart();
                formData = true;
            } else {
                multiPart = new MultiPart();
            }

            multiPart.setProviders(providers);

            if (!formData) {
                multiPart.setMediaType(mediaType);
            }

            for (MIMEPart mp : mm.getAttachments()) {
                BodyPart bodyPart = null;

                if (formData) {
                    bodyPart = new FormDataBodyPart();
                } else {
                    bodyPart = new BodyPart();
                }

                bodyPart.setProviders(providers);

                for (Header h : mp.getAllHeaders()) {
                    bodyPart.getHeaders().add(h.getName(), getFixedHeaderValue(h));
                }

                try {
                    String contentType = bodyPart.getHeaders().getFirst("Content-Type");

                    if (contentType != null) {
                        bodyPart.setMediaType(MediaType.valueOf(contentType));
                    }

                    bodyPart.getContentDisposition();
                } catch (IllegalArgumentException ex) {
                    logger.error( "readFrom error", ex );
                    throw new WebApplicationException(ex, 400);
                }

                bodyPart.setEntity(new BodyPartEntity(mp));
                multiPart.getBodyParts().add(bodyPart);
            }

            if (closeableService != null) {
                closeableService.add(multiPart);
            }

            return multiPart;
        } catch (MIMEParsingException ex) {
            logger.error( "readFrom error", ex );
            throw new WebApplicationException(ex, 400);
        }
    }

}