使用 RestKit 序列化带有子对象的对象 [POSTing]

Posted 2023-02-23

【中文标题】使用 RestKit 序列化带有子对象的对象 [POSTing]

【英文标题】：using RestKit to serialize an object with a subobject [POSTing]

【发布时间】：2012-03-13 21:16:58

【问题描述】：

我有以下对象设置：

RKObjectMapping* geoPointMapping = [RKObjectMapping mappingForClass:[CRGeoPoint class]];

geoPointMapping.setDefaultValueForMissingAttributes = YES;
[geoPointMapping mapKeyPathsToAttributes:
    @"longitude", @"longitude",
    @"latitude", @"latitude",
    nil];
[objectManager.mappingProvider registerMapping:geoPointMapping withRootKeyPath:@"geometry"];

RKObjectMapping* criteriaMapping = [RKObjectMapping mappingForClass:[CRCriteria class]];

criteriaMapping.setDefaultValueForMissingAttributes = YES;
[criteriaMapping mapKeyPathsToAttributes:
    @"type", @"type",
    @"geometry", @"geometry",
    @"fromDate", @"fromDate",
    @"toDate", @"toDate",
    @"radius", @"radius",
    nil];
[objectManager.mappingProvider registerMapping:criteriaMapping withRootKeyPath:@"criteria"];

但是当我尝试发送查询（使用几何对象）时。我一直 收到此错误：

收到错误 Error Domain=JKErrorDomain Code=-1 "无法序列化 对象类 CRGeoPoint。”

【参考方案1】：

入站和出站映射信息由RKObjectMappingProvider 分别处理。您已经在该代码中配置了入站映射（从您的服务器下载数据）。但是——RestKit 组中的as pointed out by Shane Zatezalo——您还需要为 RestKit 添加一个序列化映射，以了解如何将您的对象转换为 JSON（或您可能使用的任何其他序列化格式）。

查看对象序列化的Object Mapping tutorial's 部分。看看source for the mapping provider，让自己放心，这些东西是分开的。

【讨论】：

感谢指向文档的指针，您和 Shane 都部分正确。但是医生指出了完整答案的方法。我不仅需要创建逆映射，还需要指定用于关系的映射。

是的，我对此困惑了很长时间。最终我意识到我需要向映射提供者注册映射（由资源路径键入），并分别向路由器注册类资源路径。

【参考方案2】：

OP 的解决方案。

解决方案有两个。首先，我必须指定下面 Sixten 指出的逆映射，其次我必须指定用于 CRCriteria 对象上的 CRGeoPoint 类的映射。代码如下：

RKObjectMapping* geoPointMapping = [RKObjectMapping mappingForClass:[CRGeoPoint class]];

geoPointMapping.setDefaultValueForMissingAttributes = YES;

[objectManager.mappingProvider registerMapping:geoPointMapping withRootKeyPath:@"geometry"];

// Build a serialization mapping by inverting our object mapping. Includes attributes and relationships
RKObjectMapping* geoPointSerializationMapping = [geoPointMapping inverseMapping];
// You can customize the mapping here as necessary -- adding/removing mappings
[[RKObjectManager sharedManager].mappingProvider setSerializationMapping:geoPointSerializationMapping forClass:[CRGeoPoint class]]; 

RKObjectMapping* criteriaMapping = [RKObjectMapping mappingForClass:[CRCriteria class]];

criteriaMapping.setDefaultValueForMissingAttributes = YES;
[criteriaMapping mapKeyPathsToAttributes:
 @"type", @"type",
 @"fromDate", @"fromDate",
 @"toDate", @"toDate",
 @"radius", @"radius",
 nil];
[criteriaMapping mapKeyPath:@"geometry" toRelationship:@"geometry" withMapping:geoPointMapping];
[objectManager.mappingProvider registerMapping:criteriaMapping withRootKeyPath:@"criteria"];

// Build a serialization mapping by inverting our object mapping. Includes attributes and relationships
RKObjectMapping* criteriaSerializationMapping = [criteriaMapping inverseMapping];
// You can customize the mapping here as necessary -- adding/removing mappings
[[RKObjectManager sharedManager].mappingProvider setSerializationMapping:criteriaSerializationMapping forClass:[CRCriteria class]];