iOS: How do I set the name of an image uploading to server using Restkit
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I'm trying to upload an image from the phone to the server.  Everything is working fine, except using the code below it's using "Avatar" as the file name.  So I guess my question is, I'm giving them the choice to choose a picture, or take a picture with the camera.  Do I know which type of file it will be i.e. png, jpg or do I need to figure that out before I upload it?

    - (void)imagePickerController:(UIImagePickerController *)picker didFinishPickingMediaWithInfo:(NSDictionary *)info
    {
        UIImage *image = [info objectForKey:UIImagePickerControllerEditedImage];
    
        //self.avatarImage = [[UIImageView alloc] init];
        self.avatarImage.image = image;
        [self dismissModalViewControllerAnimated:YES];
        
        RKParams* params = [RKParams params];
        
        NSData* imageData = UIImagePNGRepresentation(image);
        [params setData:imageData MIMEType:@"image/png" forParam:@"Avatar"];
        
        NSLog(@"RKParams HTTPHeaderValueForContentType = %@", [params HTTPHeaderValueForContentType]);
        NSLog(@"RKParams HTTPHeaderValueForContentLength = %d", [params HTTPHeaderValueForContentLength]);
        
        [[RKClient sharedClient] post:@"/user/updateavatar" params:params delegate:self];
    }