FetchRequest 不 return 通过 RestKit 0.2 获取的 NSManagedObjects

Question

我遇到以下问题：我使用 RestKit 从 REST 中获取对象 Api。对象映射有效，我可以从 RK 调试器输出中看到这一点。但是，当我之后执行提取请求时，结果是空的。我说的是 NSManagedObjects。我有以下设置。

1：Restkit和Coredata栈初始化：

NSError *error;
NSURL *baseURL = [NSURL URLWithString:@"https://mfihost.us/gocoffee/api/V1/"];
RKObjectManager *objectManager = [RKObjectManager managerWithBaseURL:baseURL];
[objectManager.HTTPClient setDefaultHeader:@"Token" value:[NSString stringWithFormat:@"%@",[FBSDKAccessToken currentAccessToken].tokenString]];

objectManager.requestSerializationMIMEType = RKMIMETypeJSON;
[AFNetworkActivityIndicatorManager sharedManager].enabled = YES;
NSManagedObjectModel *managedObjectModel = [NSManagedObjectModel mergedModelFromBundles:nil];
RKManagedObjectStore *managedObjectStore = [[RKManagedObjectStore alloc] initWithManagedObjectModel:managedObjectModel];
objectManager.managedObjectStore = managedObjectStore;
//[RKObjectManager setSharedManager:objectManager];
[FetchRequests registerFetchRequests:objectManager];
[Descriptors registerDescriptors:objectManager];
[managedObjectStore createPersistentStoreCoordinator];
NSPersistentStore *persistentStore = [managedObjectStore addInMemoryPersistentStore:&error];
NSAssert(persistentStore, @"Failed to add inmemory store with error: %@", error);
[managedObjectStore createManagedObjectContexts];
managedObjectStore.managedObjectCache = [[RKInMemoryManagedObjectCache alloc] initWithManagedObjectContext:managedObjectStore.persistentStoreManagedObjectContext];

2：调用从服务器获取对象并随后执行获取请求：

[[RKObjectManager sharedManager]
     postObject:nil path:@"/gocoffee/api/V1/login/IOS"
     parameters:nil
     success: ^(RKObjectRequestOperation *operation, RKMappingResult *mappingResult) {
         NSLog(@"Objects have been saved in core data.");
         NSManagedObjectContext *managedObjCtx = [RKManagedObjectStore defaultStore].mainQueueManagedObjectContext;

        // Shout* sh=[managedObjCtx insertNewObjectForEntityForName:@"Shout"];
        // sh.inviterUserId=@"22223";

         NSFetchRequest *fetchRequest = [[NSFetchRequest alloc] init];
         NSEntityDescription *entity = [NSEntityDescription entityForName:@"Shout" inManagedObjectContext:managedObjCtx];
         [fetchRequest setEntity:entity];

         NSError *error = nil;
         NSArray *result = [managedObjCtx executeFetchRequest:fetchRequest error:&error];

         if (error) {
             NSLog(@"Unable to execute fetch request.");
             NSLog(@"%@, %@", error, error.localizedDescription);

         } else {
             NSLog(@"%@", result);
         }




         completionBlock();
     }
     failure: ^(RKObjectRequestOperation *operation, NSError *error) {
         RKLogError(@"Load failed with error: %@", error);
     }];

尽管服务器 returns 对象和这些对象已通过使用 RKEntityMappings 和相应的响应描述符正确映射，但获取结果为空。令人困惑的是，如果我取消注释这两行 //Shout * ....（即手动将托管对象插入上下文），那么该对象将由获取请求获取。因此，获取请求应该可以正常工作。我现在正在寻找年龄问题可能是什么。可能是我调用了错误的上下文或其他什么？顺便说一句：核心数据多线程调试已启用并且没有显示任何错误，即没有"AllThatIsLeftToUsIsHonor"错误。

上例对应的路由为：

[objectManager.router.routeSet
     addRoute:[RKRoute routeWithName:@"loginAndOrSignup"
                         pathPattern:@"login/IOS"
                              method:RKRequestMethodPOST]
     ];

描述符看起来像（示例）：

[objectManager addResponseDescriptor:
     [RKResponseDescriptor responseDescriptorWithMapping:[shoutMapping inverseMapping]
                                                  method:RKRequestMethodPOST
                                             pathPattern: @"login/IOS"
                                                 keyPath:@"response.incomingshoutapplications"
                                             statusCodes:RKStatusCodeIndexSetForClass(RKStatusCodeClassSuccessful)
      ]
     ];

喊映射如下：

RKEntityMapping *shoutMapping = [RKEntityMapping mappingForEntityForName:@"Shout" inManagedObjectStore:managedObjectStore];
    shoutMapping.identificationAttributes = @[ @"id" ];
    [shoutMapping addAttributeMappingsFromDictionary:@{
                                                       @"id" : @"id",
                                                       @"inviterUserId" : @"inviterUserId",
                                                       @"eventType" : @"eventType",
                                                       @"eventTime" : @"eventTime",
                                                       @"locationLat" : @"locationLat",
                                                       @"locationLng" : @"locationLng",
                                                       @"radius" : @"radius",
                                                       @"targetGender" : @"targetGender",
                                                       @"state" : @"state",
                                                       @"buddyOnly" : @"buddyOnly",
                                                       @"timeCreated" : @"timeCreated"
                                                       }
     ];

"manager" 是上面那个，managedObjectStore 是 manager.managedObjectStore 所有映射和描述符都在另一个方法中设置，该方法由 [Descriptors registerDescriptors:objectManager] 调用；（见第一段代码）

Answer 1

问题可能是您正在使用 inverseMapping。这主要用于请求映射，因为它是创建 NSMutableDictionary 实例的映射，这不是您想要的。

所以，我期望发生的是响应被成功映射，但是映射到普通对象，而不是托管对象，然后你就把结果扔掉了。

改成

... responseDescriptorWithMapping:shoutMapping ...

FetchRequest 不 return 通过 RestKit 0.2 获取的 NSManagedObjects

FetchRequest does not return NSManagedObjects fetched via RestKit 0.2

core-data

restkit