从响应中加载对象时出现错误（RestKit）

Question

从响应中加载对象时出现错误（RestKit）

6

我创建了一个针对REST响应的映射，并将其命名为“Data”。通过RKObjectManager进行REST调用后，它无法加载对象。相反，它执行了RKObjetLoader的didFailWithError方法。我的实现类继承自RKObjectLoaderDelegate。

@implementation RKObjectLoaderExamples

    -(void)loadData{
        RKObjectMapping* mapping = [RKObjectMapping mappingForClass:[Data class]];
        RKObjectManager* manager = [RKObjectManager objectManagerWithBaseURL:@"http://localhost:8080/activiti-rest/service"];  
        [manager loadObjectsAtResourcePath:@"/process-definitions?start=0&size=10&sort=id&order=asc&username=kermit&password=kermit" objectMapping:mapping delegate:self]  ;
        NSLog(@"Loaded Data");
    }

    // RKObjectLoaderDelegate methods  

    - (void)objectLoader:(RKObjectLoader*)objectLoader didLoadObjects:(NSArray*)objects {  
        NSLog(@"objectLoaded");
        Data* data = [objects objectAtIndex:0];  
        NSLog(@"Loaded Key: %@, Name: %@", data.key, data.name);  
    }  


    - (void)objectLoader:(RKObjectLoader*)objectLoader didFailWithError:(NSError*)error {  
        NSLog(@"Encountered an error: %@", error);  
    }
@end

我收到的错误信息如下：

2011-11-16 14:36:38.971 Views[16753:fb03] W restkit.network:RKResponse.m:182 Received an authentication challenge without any credentials to satisfy the request.
2011-11-16 14:36:38.974 Views[16753:fb03] W restkit.network:RKObjectLoader.m:242 Unable to find parser for MIME Type 'text/html'
2011-11-16 14:36:38.975 Views[16753:fb03] W restkit.network:RKObjectLoader.m:259 Encountered unexpected response with status code: 401 (MIME Type: text/html)
2011-11-16 14:36:38.976 Views[16753:fb03] Encountered an error: Error Domain=org.restkit.RestKit.ErrorDomain Code=4 "The operation couldn’t be completed. (org.restkit.RestKit.ErrorDomain error 4.)"

请帮帮我！

修改后，我将函数更改为：

-(void)loadData{

    [RKClient setSharedClient:[[RKClient alloc] initWithBaseURL:@"http://localhost:8080/activiti-rest/service"]];
    RKObjectMapping* mapping = [RKObjectMapping mappingForClass:[Data class]];
    RKObjectManager* manager = [RKObjectManager objectManagerWithBaseURL:@"http://localhost:8080/activiti-rest/service"];  
     [manager setClient:[RKClient sharedClient]];
    [[RKClient sharedClient] setUsername:@"kermit"];
    [[RKClient sharedClient] setPassword:@"kermit"];
    [manager loadObjectsAtResourcePath:@"/process-definitions?start=0&size=10&sort=id&order=asc" objectMapping:mapping delegate:self]  ;
    NSLog(@"Loaded Data");

}

这样做正确吗？因为现在对象似乎已经加载，但是我得到了一个空数组的索引0超出范围的错误。我做错了吗？

- Anusha Pachunuri

1个回答

网页内容由stack overflow 提供, 点击上面的

可以查看英文原文，
原文链接

- mja · Accepted Answer

您的API返回HTTP错误401未经授权。您的后端是否需要HTTP身份验证？如果是，请向RKClient提供正确的凭据：

[[RKClient sharedClient] setUsername:myUsername];
[[RKClient sharedClient] setPassword:myPassword];

编辑：

我认为在设置RestKit时您存在一些基本问题。请考虑以下示例。

//in your appdelegate
RKObjectManager* manager = [RKObjectManager objectManagerWithBaseURL:@"http://localhost:8080/activiti-rest/service"]; 
[[RKClient sharedClient] setUsername:@"kermit"];
[RKClient sharedClient] setPassword:@"kermit"];

// don't forget to create your mapping here
RKObjectMapping *dataMapping = [RKObjectMapping mappingForClass:[Data class]];
[dataMapping mapKeyPath:@"myKeyPath" toAttribute:@"myAttr"];
[[manager mappingProvider] addObjectMapping: dataMapping];

然后，你只需这样做。

 -(void)loadData{
    // fetch your mapping
    [RKObjectMapping *mapping = [[RKObjectManager sharedManager].mappingProvider objectMappingForClass:[Data class]]; 
    //request data
    [[RKObjectManager sharedManager] loadObjectsAtResourcePath:@"/process-definitions?start=0&size=10&sort=id&order=asc" objectMapping:mapping delegate:self];
}

首先，您需要进行设置（RKClient、映射和RKObjectManager） - 只需进行一次设置。它们是单例模式，因此设置将被保存。我发现这样做的最佳位置是AppDelegate - 可以随意尝试，但请确保在进行任何请求之前进行设置。

当您要执行任何请求时，只需使用您的[[RKObjectManager sharedManager]单例加载实际对象。

此外，我建议阅读一些文档，例如对象映射指南。