RestKit发布失败的URL密钥

Question

我正在开发一款使用RestKit的iPhone应用程序。我在将对象发布到服务器时遇到问题。当我保存一个帖子时，它显示在TableView提要中，但它不会保存到服务器。 我在xcode中遇到错误说：

Object request failed: Underlying HTTP request operation failed with error: Error Domain=org.restkit.RestKit.ErrorDomain Code=-1011 "Expected status code in (200-299), got 500"

然后在控制台中我得到了：

AFNetworkingOperationFailingURLRequestErrorKey=<NSMutableURLRequest https://stormy.herokuapp.com/posts>, NSErrorFailingURLKey=https://stormy.herokuapp.com/posts, NSLocalizedDescription=Expected status code in (200-299), got 500, AFNetworkingOperationFailingURLResponseErrorKey=<NSHTTPURLResponse: 0x841d450>}

我的NSManagedObject MPost看起来像

@interface MPost：NSManagedObject

@property (nonatomic, retain) NSNumber * postID;
@property (nonatomic, retain) id jsonURL;
@property (nonatomic, retain) id htmlURL;
@property (nonatomic, retain) NSString * bodyText;
@property (nonatomic, retain) NSDate * createdAt;
@property (nonatomic, retain) MUser *user;

这是我的AppDelegate

    - (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
    {
        NSError *error = nil;
        NSURL *modelURL = [NSURL fileURLWithPath:[[NSBundle mainBundle] pathForResource:@"Markofresh" ofType:@"momd"]];
        // NOTE: Due to an iOS 5 bug, the managed object model returned is immutable.
        NSManagedObjectModel *managedObjectModel = [[[NSManagedObjectModel alloc] initWithContentsOfURL:modelURL] mutableCopy];
        RKManagedObjectStore *managedObjectStore = [[RKManagedObjectStore alloc] initWithManagedObjectModel:managedObjectModel];

        // Initialize the Core Data stack
        [managedObjectStore createPersistentStoreCoordinator];

        NSPersistentStore __unused *persistentStore = [managedObjectStore addInMemoryPersistentStore:&error];
        NSAssert(persistentStore, @"Failed to add persistent store: %@", error);

        [managedObjectStore createManagedObjectContexts];

        // Configure a managed object cache to ensure we do not create duplicate objects
        managedObjectStore.managedObjectCache = [[RKInMemoryManagedObjectCache alloc] initWithManagedObjectContext:managedObjectStore.persistentStoreManagedObjectContext];


        // Set the default store shared instance
        [RKManagedObjectStore setDefaultStore:managedObjectStore];

        // Configure the object manager
        RKObjectManager *objectManager = [RKObjectManager managerWithBaseURL:[NSURL URLWithString:@"https://stormy.herokuapp.com"]];
        objectManager.managedObjectStore = managedObjectStore;

        [RKObjectManager setSharedManager:objectManager];

        RKEntityMapping *entityMapping = [RKEntityMapping mappingForEntityForName:@"Post" inManagedObjectStore:managedObjectStore];
        [entityMapping addAttributeMappingsFromDictionary:@{
         @"id":             @"postID",
         @"url":            @"jsonURL",
         @"body":           @"bodyText",
         @"public":         @"public",
         @"created_at":     @"createdAt"}];
        entityMapping.identificationAttributes = @[ @"postID" ];

        RKResponseDescriptor *responseDescriptor = [RKResponseDescriptor responseDescriptorWithMapping:entityMapping pathPattern:@"/posts" keyPath:nil statusCodes:RKStatusCodeIndexSetForClass(RKStatusCodeClassSuccessful)];

        [objectManager addResponseDescriptor:responseDescriptor];

        RKRequestDescriptor * requestDescriptor = [RKRequestDescriptor requestDescriptorWithMapping:[entityMapping inverseMapping] objectClass:[MPost class] rootKeyPath:@"/posts"];
        [objectManager addRequestDescriptor:requestDescriptor];

   RKObjectMapping *responseMapping = [RKObjectMapping mappingForClass:[MPost class]];
    [responseMapping addAttributeMappingsFromArray:@[@"bodyText", @"postID", @"createdAt"]];
    NSIndexSet *statusCodes = RKStatusCodeIndexSetForClass(RKStatusCodeClassSuccessful); // Anything in 2xx
    RKResponseDescriptor *postDescriptor = [RKResponseDescriptor responseDescriptorWithMapping:responseMapping pathPattern:@"/posts" keyPath:@"/posts" statusCodes:statusCodes];

    RKObjectMapping *requestMapping = [RKObjectMapping requestMapping]; // objectClass == NSMutableDictionary
    [requestMapping addAttributeMappingsFromArray:@[@"bodyText", @"postID", @"createdAt"]];

    RKRequestDescriptor *requestDescriptor = [RKRequestDescriptor requestDescriptorWithMapping:requestMapping objectClass:[MPost class] rootKeyPath:@"posts"];

    RKObjectManager *manager = [RKObjectManager managerWithBaseURL:[NSURL URLWithString:@"https://stormy.herokuapp.com"]];
    [manager addRequestDescriptor:requestDescriptor];
    [manager addResponseDescriptor:postDescriptor];

    [objectManager addRequestDescriptor:requestDescriptor];

        // Override point for customization after application launch.
        UINavigationController *navigationController = (UINavigationController *)self.window.rootViewController;
        MasterViewController *controller = (MasterViewController *)navigationController.topViewController;
        controller.managedObjectContext = managedObjectStore.mainQueueManagedObjectContext;
        return YES;
    }

NewPost类中的savePost方法是：

-(void)saveChanges {
    RKManagedObjectStore *objectStore = [[RKObjectManager sharedManager] managedObjectStore];
    MPost *post = [NSEntityDescription insertNewObjectForEntityForName:@"Post" inManagedObjectContext:objectStore.mainQueueManagedObjectContext];
    [post setBodyText:@"This is the body."];

    [[RKObjectManager sharedManager] postObject:post path:@"/posts" parameters:nil success:^(RKObjectRequestOperation *operation, RKMappingResult *mappingResult) {
        NSLog(@"Success saving post");
    } failure:^(RKObjectRequestOperation *operation, NSError *error) {
        NSLog(@"Failure saving post: %@", error.localizedDescription);
    }];

有什么想法吗？

它是否失败，因为我有一个user_id presenece：我的rails应用程序模型中的真正parmam - 但我的xcode应用程序中没有用户？ 或者它是xcode和rails中的类声明之间的差异吗？

EDIT 这是来自成功帖子的服务器日志

2013-06-18T17:46:41.822383+00:00 app[web.1]: Started POST "/posts" for 76.171.148.52 at 2013-06-18 17:46:41 +0000
2013-06-18T17:46:41.825320+00:00 app[web.1]:   Parameters: {"utf8"=>"✓", "authenticity_token"=>"8VvNPJXOuTNvS4ewEmXAvYHkcyKAnktHrpfQhRgHFy4=", "post"=>{"body"=>"shyea"}, "commit"=>"Create Post"}
2013-06-18T17:46:41.825160+00:00 app[web.1]: Processing by PostsController#create as HTML
2013-06-18T17:46:41.943001+00:00 app[web.1]: Redirected to https://stormy-river-3647.herokuapp.com/posts/4
2013-06-18T17:46:41.943001+00:00 app[web.1]: Completed 302 Found in 116ms (ActiveRecord: 7.8ms)
2013-06-18T17:46:42.410628+00:00 heroku[router]: at=info method=GET path=/posts/4 host=stormy-river-3647.herokuapp.com fwd="76.171.148.52" dyno=web.1 connect=1ms service=66ms status=200 bytes=2040
2013-06-18T17:46:42.353386+00:00 app[web.1]: Started GET "/posts/4" for 76.171.148.52 at 2013-06-18 17:46:42 +0000
2013-06-18T17:46:42.357829+00:00 app[web.1]: Processing by PostsController#show as HTML
2013-06-18T17:46:42.366143+00:00 app[web.1]:   Parameters: {"id"=>"4"}
2013-06-18T17:46:42.381884+00:00 app[web.1]:   Rendered posts/show.html.erb within layouts/application (4.0ms)
2013-06-18T17:46:41.943499+00:00 heroku[router]: at=info method=POST path=/posts host=stormy.herokuapp.com fwd="76.171.148.52" dyno=web.1 connect=1ms service=142ms status=302 bytes=113

这是在发布失败后的服务器日志中：

    2013-06-18T22:55:01.571679+00:00 app[web.1]: Started POST "/posts" for 76.171.148.52 at 2013-06-18 22:55:01 +0000
2013-06-18T22:55:01.579270+00:00 app[web.1]: WARNING: Can't verify CSRF token authenticity
2013-06-18T22:55:01.579270+00:00 app[web.1]: Processing by PostsController#create as JSON
2013-06-18T22:55:01.578909+00:00 app[web.1]:   app/controllers/posts_controller.rb:39:in `create'
2013-06-18T22:55:01.578909+00:00 app[web.1]: NoMethodError (undefined method `posts' for nil:NilClass):
2013-06-18T22:55:01.579270+00:00 app[web.1]:   Parameters: {"post"=>{"body"=>"This is the body."}}
2013-06-18T22:55:01.579270+00:00 app[web.1]: Completed 500 Internal Server Error in 1ms

铁路方面有问题吗？在posts_controller中？