Get Twitter oauth key in similar way to Facebook oauth key

I have an iPhone app which current开发者_开发问答ly loads up a UIWebView using the facebook graph api oauth url (https://graph.facebook.com/oauth/authorize?...) - a user then enters their login details, and on submitting I retrieve the the access token from the URL. (In a manner as this I believe http://www.capturetheconversation.com/technology/iphone-facebook-oauth2-graph-api) This is then passed to my java server which performs the various actions using RestFB

My question is, is there a similar way to do this with Twitter? Currently it seems the only way to get the data is to download a library and use that; yet this is an approach I would rather not use as it would take up unnecessary space seeing as all the commands will actually be run from my Java server.

Any advice would be greatly appreciated

Thanks,

Dan

Twitter uses OAuth 1.0a authentication, but not OAuth 2.0.

Steps to get an access token on Twitter:

1. Create your own application on Twitter and get consumer key and secret.
2. Download open source OAuth library, OAuthConsumer in my case.
3. Write registration code, see example below.

p.s. Set application type as web application, it turns on callback instead of PIN code.

static NSString* kMyApplicationConsumerKey = @"XXXXXXXXXXX";
static NSString* kMyApplicationConsumerSecret = @"XXXXXXXXXXX";


@interface TwitterConnector : NSObject {
    OAConsumer* consumer;
    OAToken* requestToken;
    OAToken* accessToken;
}

- (void)start;

@end

@implementation TwitterConnector

- (void)start {
    consumer = [[OAConsumer alloc] initWithKey:kMyApplicationConsumerKey secret:kMyApplicationConsumerSecret];

    NSURL* requestTokenUrl = [NSURL URLWithString:@"http://api.twitter.com/oauth/request_token"];
    OAMutableURLRequest* requestTokenRequest = [[[OAMutableURLRequest alloc] initWithURL:requestTokenUrl
                                                                                consumer:consumer 
                                                                                   token:nil
                                                                                   realm:nil
                                                                       signatureProvider:nil] autorelease];
    OARequestParameter* callbackParam = [[[OARequestParameter alloc] initWithName:@"oauth_callback" value:@"twitter://authorized"] autorelease];
    [requestTokenRequest setHTTPMethod:@"POST"];
    [requestTokenRequest setParameters:[NSArray arrayWithObject:callbackParam]];
    OADataFetcher* dataFetcher = [[[OADataFetcher alloc] init] autorelease];
    [dataFetcher fetchDataWithRequest:requestTokenRequest
                             delegate:self 
                    didFinishSelector:@selector(didReceiveRequestToken:data:)
                      didFailSelector:@selector(didFailOAuth:error:)];
}

- (void)didReceiveRequestToken:(OAServiceTicket*)ticket data:(NSData*)data {
    NSString* httpBody = [[[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding] autorelease];
    requestToken = [[OAToken alloc] initWithHTTPResponseBody:httpBody];

    NSURL* authorizeUrl = [NSURL URLWithString:@"https://api.twitter.com/oauth/authorize"];
    OAMutableURLRequest* authorizeRequest = [[[OAMutableURLRequest alloc] initWithURL:authorizeUrl
                                                                             consumer:nil 
                                                                                token:nil
                                                                                realm:nil
                                                                    signatureProvider:nil] autorelease];
    NSString* oauthToken = requestToken.key;
    OARequestParameter* oauthTokenParam = [[[OARequestParameter alloc] initWithName:@"oauth_token" value:oauthToken] autorelease];
    [authorizeRequest setParameters:[NSArray arrayWithObject:oauthTokenParam]];

    UIWebView* webView = [[UIWebView alloc] initWithFrame:[UIScreen mainScreen].bounds];
    [[[UIApplication sharedApplication] keyWindow] addSubview:webView];
    [webView release];

    webView.delegate = self;
    [webView loadRequest:authorizeRequest];
}

- (void)didReceiveAccessToken:(OAServiceTicket*)ticket data:(NSData*)data {
    NSString* httpBody = [[[NSString alloc] initWithData:data encoding:NSUTF8StringEncoding] autorelease];
    accessToken = [[OAToken alloc] initWithHTTPResponseBody:httpBody];

    // FINISHED!
}

- (void)didFailOAuth:(OAServiceTicket*)ticket error:(NSError*)error {
    // ERROR!
}

////////////////////////////////////////////////////////////////////////////////////////////////////////////////////
#pragma mark UIWebViewDelegate

- (BOOL)webView:(UIWebView*)webView shouldStartLoadWithRequest:(NSURLRequest*)request navigationType:(UIWebViewNavigationType)navigationType {
    if ([[[request URL] scheme] isEqualToString:@"twitter"]) {

        // Extract oauth_verifier from URL query
        NSString* verifier = nil;       
        NSArray* urlParams = [[[request URL] query] componentsSeparatedByString:@"&"];
        for (NSString* param in urlParams) {
            NSArray* keyValue = [param componentsSeparatedByString:@"="];
            NSString* key = [keyValue objectAtIndex:0];
            if ([key isEqualToString:@"oauth_verifier"]) {
                verifier = [keyValue objectAtIndex:1];
                break;
            }
        }

        if (verifier) {
            NSURL* accessTokenUrl = [NSURL URLWithString:@"https://api.twitter.com/oauth/access_token"];
            OAMutableURLRequest* accessTokenRequest = [[[OAMutableURLRequest alloc] initWithURL:accessTokenUrl
                                                                                       consumer:consumer 
                                                                                          token:requestToken
                                                                                          realm:nil
                                                                              signatureProvider:nil] autorelease];
            OARequestParameter* verifierParam = [[[OARequestParameter alloc] initWithName:@"oauth_verifier" value:verifier] autorelease];
            [accessTokenRequest setHTTPMethod:@"POST"];
            [accessTokenRequest setParameters:[NSArray arrayWithObject:verifierParam]];
            OADataFetcher* dataFetcher = [[[OADataFetcher alloc] init] autorelease];
            [dataFetcher fetchDataWithRequest:accessTokenRequest
                                     delegate:self 
                            didFinishSelector:@selector(didReceiveAccessToken:data:)
                              didFailSelector:@selector(didFailOAuth:error:)];
        } else {
            // ERROR!
        }

        [webView removeFromSuperview];

        return NO;
    }
    return YES;
}

- (void)webView:(UIWebView*)webView didFailLoadWithError:(NSError*)error {
    // ERROR!
}

@end