RestKit 将 JSON 对象节点分解为核心数据

Question

我有一个 JSON 结构，需要将其分解为几个核心数据表。然而，我返回的 JSON 并未真正标准化为结构，我可以弄清楚如何将它们拆分为对象。我有 4 个表，歌曲、艺术家、专辑、流派。

JSON：

{
"Songs": [
{
"strFileID": "b7eccc27-b099-4ea2-93c5-5004f6d2e31d",
"strFileName": "07-Cryin.mp3",
"strDuration": "00:05:09.812",
"strAlbumTitle": "Big Ones",
"strArtists": "Aerosmith",
"strTrackNumber": 7,
"strGenre": "Rock",
"strTitle": "07-Cryin.mp3"
}
]
}

由于 strArtists 没有拆分成它自己的对象，而只是一个元素，因此我无法弄清楚如何创建映射以确保只有“Aerosmith”被提取到它自己的表中，然后再关联回来。

目前，我以以下内容为起点来获取歌曲和艺术家：

    RKManagedObjectMapping *artistMapping = [RKManagedObjectMapping mappingForClass:[Artist class]];
    artistMapping.primaryKeyAttribute = ArtistAttributes.artistName;
    [artistMapping mapKeyPath:@"Song.strArtists" toAttribute:ArtistAttributes.artistName];

    RKManagedObjectMapping *songMapping = [RKManagedObjectMapping mappingForClass:[Song class]];
    songMapping.primaryKeyAttribute = SongAttributes.fileId;
    [songMapping mapKeyPath:@"strFileID" toAttribute:SongAttributes.fileId];
    [songMapping mapKeyPath:@"strFileName" toAttribute:SongAttributes.fileName];
    [songMapping mapKeyPath:@"strTitle" toAttribute:SongAttributes.title];
    [songMapping mapKeyPath:@"strDuration" toAttribute:SongAttributes.duration];
    [songMapping mapKeyPath:@"strTrackNumber" toAttribute:SongAttributes.trackNumber];

    [songMapping mapRelationship:@"artist" withMapping:artistMapping];

    [objectManager.mappingProvider setMapping:songMapping forKeyPath:@"Song"];
    [objectManager.mappingProvider setMapping:artistMapping forKeyPath:@"strArtists"];