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

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