将一个对象映射到两个类的CoreData

Question

因此，这是我第一次尝试将对象映射到CoreData中，我认为它是正确的，但我没有几个问题。首先，我只是不知道我是否以正确的方式进行了映射，其次是我得到了成功响应，但没有映射对象。

我有2个对象DbRestError & DbRestCategory。 DbRestError包含来自服务器的错误，并且DbRestCategory包含类别本身。都是从相同的响应回来，但RestKit似乎无法映射它们。

这些都是对象：

DbRestError

@interface DbRestError : NSManagedObject 

@property (nonatomic, retain) NSNumber * statusCode; 
@property (nonatomic, retain) NSString * errorTitle; 

@end 

DbRestCategory

@interface DbRestCategory : NSManagedObject 

@property (nonatomic, retain) NSString * title; 
@property (nonatomic, retain) NSNumber * idNum; 

@end 

这是我初始化我CoreData与RestKit：

- (void)setup 
{ 
    self.objectStore = [[RKManagedObjectStore alloc] initWithManagedObjectModel:[self managedObjectModel]]; 

    NSString *path = [RKApplicationDataDirectory() stringByAppendingPathComponent:@"database.sqlite"]; 
    NSLog(@"Setting up store at %@", path); 
    [self.objectStore addSQLitePersistentStoreAtPath:path 
           fromSeedDatabaseAtPath:nil 
            withConfiguration:nil 
              options:@{ NSInferMappingModelAutomaticallyOption: @YES, NSMigratePersistentStoresAutomaticallyOption: @YES } 
               error:nil]; 

    [self.objectStore createManagedObjectContexts]; 
} 

这是我初始化我RestKit客户端：

- (void)initRestClient 
{ 
    NSURL *baseURL = [NSURL URLWithString:kWebServiceBaseURL]; 
    self.manager = [RKObjectManager managerWithBaseURL:baseURL]; 
    [self.manager setRequestSerializationMIMEType:RKMIMETypeJSON]; 
    [self.manager setAcceptHeaderWithMIMEType:RKMIMETypeJSON]; 
    [self.manager addResponseDescriptorsFromArray:[RKObjectManager sharedManager].responseDescriptors]; 
    [self.manager addRequestDescriptorsFromArray:[RKObjectManager sharedManager].requestDescriptors]; 
    [self.manager.HTTPClient.operationQueue setMaxConcurrentOperationCount:MAX_CONCURRENT_OPERATION_COUNT]; 
    [self.manager setManagedObjectStore:[[MainDb sharedDb] objectStore]]; 

    [RKObjectManager setSharedManager:self.manager]; 

    self.requestMethod = RKRequestMethodGET; 
    self.statusCode = RKStatusCodeIndexSetForClass(RKStatusCodeClassSuccessful); 

    RKRoute *categoriesRoute = [RKRoute routeWithClass:[DbRestCategory class] pathPattern:kGetCategories method:self.requestMethod]; 
    categoriesRoute.shouldEscapePath = YES; 
    [self.manager.router.routeSet addRoute:categoriesRoute]; 

    // @@yosi -- Error Mapping 
    // 
    // 
    RKEntityMapping *errorMapping = [RKEntityMapping mappingForEntityForName:@"DbRestError" inManagedObjectStore:[[MainDb sharedDb] objectStore]]; 
    [errorMapping addAttributeMappingsFromDictionary:@{ @"statusCode" : @"statusCode", @"description" : @"errorTitle" }]; 

    // @@yosi -- Categories Mapping 
    // 
    // 
    RKEntityMapping *categoryMapping = [RKEntityMapping mappingForEntityForName:@"DbRestCategory" inManagedObjectStore:[[MainDb sharedDb] objectStore]]; 
    [categoryMapping addAttributeMappingsFromDictionary:@{ @"id" : @"idNum", @"name" : @"title" }]; 

    RKObjectMapping *categoriesMapping = [RKObjectMapping mappingForClass:[RestCategories class]]; 
    [categoriesMapping addRelationshipMappingWithSourceKeyPath:@"categories" mapping:categoryMapping]; 
    [categoriesMapping addPropertyMapping:[RKRelationshipMapping relationshipMappingFromKeyPath:@"error" toKeyPath:@"error" withMapping:errorMapping]]; 

    [[RKObjectManager sharedManager] addResponseDescriptor:[RKResponseDescriptor responseDescriptorWithMapping:categoriesMapping 
                             method:self.requestMethod 
                            pathPattern:kGetCategories 
                             keyPath:nil 
                            statusCodes:self.statusCode]]; 
} 

这就是我正在做的请求本身：

[[RKObjectManager sharedManager] getObject:[[DbRestCategory alloc] init] path:nil parameters:nil success:^(RKObjectRequestOperation *operation, RKMappingResult *mappingResult) { 

} failure:^(RKObjectRequestOperation *operation, NSError *error) { 

}]; 

这是怎样的JSON看起来像：

{ 
error: { 
statusCode: 10, 
description: "success" 
}, 
categories: [ 
    { 
     id: "3", 
    name: "cate 3" 
    }, 
    { 
     id: "4", 
    name: "cate 4" 
    }, 
    { 
     id: "5", 
    name: "cate 5" 
    }, 
    { 
     id: "1", 
    name: "cate 1" 
    }, 
    { 
     id: "6", 
    name: "cate 6" 
    }, 
    { 
     id: "2", 
    name: "cate 2" 
    } 
      ] 
} 

有人可以帮我理解为什么我没有任何物体得到回应吗？

Answer 1

尝试请求映射像这样，

// Request Mapping 

// Map error 
RKEntityMapping *errorMapping = [RKEntityMapping mappingForEntityForName:@"DbRestError" inManagedObjectStore:[[MainDb sharedDb] objectStore]]; 
[errorMapping addAttributeMappingsFromDictionary:@{ @"statusCode" : @"statusCode", @"description" : @"errorTitle" }]; 
[[RKObjectManager sharedManager] addResponseDescriptor:[RKResponseDescriptor responseDescriptorWithMapping:errorMapping method:self.requestMethod pathPattern:kGetCategories keyPath:@"error" statusCodes:self.statusCode]]; 

// Map Category 
RKEntityMapping *categoryMapping = [RKEntityMapping mappingForEntityForName:@"DbRestCategory" inManagedObjectStore:[[MainDb sharedDb] objectStore]]; 
[categoryMapping addAttributeMappingsFromDictionary:@{ @"id" : @"idNum", @"name" : @"title" }]; 

[[RKObjectManager sharedManager] addResponseDescriptor:[RKResponseDescriptor responseDescriptorWithMapping:categoriesMapping method:self.requestMethod pathPattern:kGetCategories keyPath:@"categories" statusCodes:self.statusCode]];