Re: [aerogear-dev] iOS/CoreData - API proposal - AGEntityMapper

how the mapper deals with nested objects? On 04/01/2013, at 08:55, Matthias Wessendorf <matzew(a)apache.org&gt; wrote: > CoreData: API proposal - AGEntityMapper > Background > Mapping JSON representations to a "rich" domain model in ObjC is a bit cumbersome. Similar is true when mapping a JSON data/response to a NSMangedObject (and vise versa). There is a base framework for "remote persistence", via the CoreData API, by leveraging a custom NSIncrementalStore -> AFIncrementalStore. > > For that,... a similar two-way-mapping is required, as described here. > > AeroGear and CoreData > Our CoreData offerings are leveraging the AFIncrementalStore, therefore (as with other frameworks/libraries) we need a mapping as well. We need to know the name of the entity and we need a NSDictionary that covers the actual JSON/property mapping. It could be done with the vanialla ObjC classes: > > // some mappers: > NSDictionary *task_mapper = > > > [NSDictionary dictionaryWithObjectsAndKeys:@"description",@"desc",@"id",@"myId", nil]; > NSDictionary *project_mapper = > > > [NSDictionary dictionaryWithObjectsAndKeys:@"id",@"myId", nil]; > > > > // create a schema out of the mappers: > NSDictionary *schema = > > > [NSDictionary dictionaryWithObjectsAndKeys:task_mapper, @"Task", project_mapper, @"Project", nil]; > > > > // pass the schema to the AGCoreDataHelper class, when doing the init... > Proposal for a custom API > I'd like to introduce a new wrapper type, called AGEntityMapper: > > @interface AGEnityMapper : NSObject > > > > @property NSString *name; > @property NSDictionary *mapper; > > > > -(id) initWithName:(NSString *) name mapper:(NSDictionary *) mapper; > @end > This AGEntityMapper would be applied onto the AGCoreDataConfig: > > @protocol AGCoreDataConfig <NSObject> > > > > @property (strong, nonatomic) NSManagedObjectModel *managedObjectModel; > @property (strong, nonatomic) NSURL *baseURL; > > > > -(void)applyEntityMappers:(AGEnityMapper *)firstObject, ... NS_REQUIRES_NIL_TERMINATION; > > > > @end > The actual code, would look like this: > > EnityMapper *taskMapper = > > > [[EnityMapper alloc] initWithName:@"Task" > > > // mapping the properties on the "entity" (NSManagedObject) > > > // to the external representation (e.g. JSON) > > > mapper:@{ @"desc": @"description", @"myId": @"id"}]; > > > > EnityMapper *projectMapper = > > > [[EnityMapper alloc] initWithName:@"Project" > > > // mapping the properties on the "entity" (NSManagedObject) > > > // to the external representation (e.g. JSON) > > > mapper:@{ @"myId": @"id"}]; > > > > AGCoreDataHelper *helper = [[AGCoreDataHelper alloc] initWithConfig:^(id<AGCoreDataConfig> config) { > > > > [config setBaseURL:[NSURL URLWithString:@"http://server.com"]]; > > > > [config applyEntityMappers: > > > taskMapper, > > > projectMapper, > > > nil // terminate the varargs. > > > ]; > }]; > > -- > Matthias Wessendorf > > blog: http://matthiaswessendorf.wordpress.com/ > sessions: http://www.slideshare.net/mwessendorf > twitter: http://twitter.com/mwessendorf > _______________________________________________ > aerogear-dev mailing list > aerogear-dev(a)lists.jboss.org > https://lists.jboss.org/mailman/listinfo/aerogear-dev _______________________________________________ aerogear-dev mailing list aerogear-dev(a)lists.jboss.org https://lists.jboss.org/mailman/listinfo/aerogear-dev