View Full Version : twitpic API help (multipart/form-data upload)

Nov 21, 2009, 08:44 PM
I've put together this code from lots of research.
Information on the twitpic API is here: Twitpic - Share photos on Twitter (http://twitpic.com/api.do#uploadAndPost)

Through debugging i can tell that the dictionary is good, and that it gets through all the methods, the request gets submitted, but then the NSLog method returns <>.

I'm not sure where I could be going wrong, i don't know much about the multipart/form-data structure. Maybe I'm doing something wrong with my connection?

Code below.

-(void)uploadBoth {
//Create dictionary of post arguments
NSArray *keys = [[NSArray alloc] initWithObjects:@"media",@"username",@"password",@"message",nil];
NSArray *objects = [[NSArray alloc] initWithObjects:
imageData, twitterUserSave, twitterPassSave, [NSString stringWithFormat:@"%@",messageView.text], nil];

NSDictionary *keysDict = [[NSDictionary alloc] initWithObjects:objects forKeys:keys];
NSLog(@"%@", keysDict);

//create twitpic photo post
NSURLRequest *twitpicPost = [self twitpicRequest:keysDict withData:imageData];

//send request, return YES if successful
NSURLConnection *twitpicConnection = [[NSURLConnection alloc] initWithRequest: twitpicPost delegate:self];

if (!twitpicConnection) {
NSLog(@"Failed to submit request");
} else {
NSLog(@"Request submitted");
NSData *receivedData = [[NSMutableData data] retain];
NSLog(@"%@", receivedData); // THIS PART RETURNS <>

The NSURLRequest part

-(NSURLRequest *)twitpicRequest:(NSDictionary *)postKeys withData:(NSData *)data {

NSLog(@"got this far");

//create the URL POST Request to twitpic
NSURL *twitpicURL = [NSURL URLWithString:@"http://twitpic.com/api/uploadAndPost"];
NSMutableURLRequest *twitpicPost = [NSMutableURLRequest requestWithURL:twitpicURL];
[twitpicPost setHTTPMethod:@"POST"];

//Add the header info
NSString *stringBoundary = [NSString stringWithString:@"0xAbCdEfGbOuNdArY"];
NSString *contentType = [NSString stringWithFormat:@"multipart/form-data; boundary=%@",stringBoundary];
[twitpicPost addValue:contentType forHTTPHeaderField: @"Content-Type"];

//create the body
NSMutableData *postBody = [NSMutableData data];
[postBody appendData:[[NSString stringWithFormat:@"--%@\r\n",stringBoundary] dataUsingEncoding:NSUTF8StringEncoding]];

//add key values from the NSDictionary object
NSEnumerator *keys = [postKeys keyEnumerator];
int i;
for (i = 0; i < [postKeys count]; i++) {
NSString *tempKey = [keys nextObject];
[postBody appendData:[[NSString stringWithFormat:@"Content-Disposition: form-data; name=\"%@\"\r\n\r\n",tempKey] dataUsingEncoding:NSUTF8StringEncoding]];
[postBody appendData:[[NSString stringWithFormat:@"%@",[postKeys objectForKey:tempKey]] dataUsingEncoding:NSUTF8StringEncoding]];
[postBody appendData:[[NSString stringWithFormat:@"\r\n--%@\r\n",stringBoundary] dataUsingEncoding:NSUTF8StringEncoding]];

//add data field and file data
[postBody appendData:[[NSString stringWithString:@"Content-Disposition: form-data; name=\"data\"\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
[postBody appendData:[[NSString stringWithString:@"Content-Type: application/octet-stream\r\n\r\n"] dataUsingEncoding:NSUTF8StringEncoding]];
[postBody appendData:[NSData dataWithData:data]];
[postBody appendData:[[NSString stringWithFormat:@"\r\n--%@--\r\n",stringBoundary] dataUsingEncoding:NSUTF8StringEncoding]];

//add the body to the post
[twitpicPost setHTTPBody:postBody];

return twitpicPost;