Using Scribe, OAuth Echo doesn't seem to work with Twitpic

Question

I'm trying to upload photos using Scribe, and it doesn't seem to work with getting an error:

Authentication challenged received is null

And I have no idea, due to the lack of documentation on the matter how to fix this.

The relevant code is:

try{
        OAuthRequest r = new OAuthRequest(Verb.POST, url);
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        toSend.writeTo(out);
        r.addPayload(out.toByteArray());
        r.addHeader(toSend.getContentType().getName(), toSend.getContentType().getValue());

        OAuth10aServiceImpl oauth = (OAuth10aServiceImpl)oauthImpl;
        OAuthRequest sr = new OAuthRequest(Verb.GET, serviceProvider);
        sr.addOAuthParameter(OAuthConstants.TOKEN, oauthToken.getToken());
        sr.addOAuthParameter(OAuthConstants.REALM,"http://api.twitter.com/");
        oauth.addOAuthParams(sr, client._oauthToken);

        r.addHeader("X-Auth-Service-Provider",serviceProvider);
        String oauthHeader = oauth.api.getHeaderExtractor().extract(sr);
        r.addHeader("X-Verify-Credentials-Authorization", oauthHeader);

        System.out.println(r.getHeaders().get("X-Verify-Credentials-Authorization"));

        return r.send();
    }catch(Exception e){
        e.printStackTrace();
        return null;
    }

I'm thinking it's something with the consumer key, as it doesn't seem to be added to the signature, but I'm not too sure what's really going on :/

Any help would be appreciated

Answer 1

Fixed. Here is the code:

        OAuthRequest r = new OAuthRequest(Verb.POST, url);
        ByteArrayOutputStream out = new ByteArrayOutputStream();
        toSend.writeTo(out);
        r.addPayload(out.toByteArray());
        r.addHeader(toSend.getContentType().getName(), toSend.getContentType().getValue());

        OAuth10aServiceImpl oauth = (OAuth10aServiceImpl)client._oauth;
        OAuthRequest sr = new OAuthRequest(Verb.GET, serviceProvider);
        oauth.signRequest(client._oauthToken, sr);

        r.addHeader("X-Auth-Service-Provider",serviceProvider);
        String oauthHeader = sr.getHeaders().get("Authorization");
        r.addHeader("X-Verify-Credentials-Authorization", oauthHeader);

For anyone wanting to know how this works, toSend is a HttpEntity containing the file and other StringBody parts and client._oauthToken is a Token object. r is my request to twitpic and serviceProvider is the Twitter API verify credentials url (which changes on some services like yfrog)