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copied!<p>Ok, so this wasn't too hard after all. Here is a class I wrote just for this (no disclaimers, it works for us and may be useful for someone else). You can use this as a direct replacement to the standard RKObjectLoader class.</p> <p>.h file</p> <pre><code>#import <RestKit/RestKit.h> #import "ASIFormDataRequest.h" @interface ASIHTTPObjectLoader : ASIFormDataRequest <RKObjectMapperDelegate> { RKObjectManager* _objectManager; RKObjectMapping* _objectMapping; RKObjectMappingResult* _result; RKObjectMapping* _serializationMapping; NSString* _serializationMIMEType; NSObject* _sourceObject; NSObject* _targetObject; } @property (nonatomic, retain) RKObjectMapping* objectMapping; @property (nonatomic, readonly) RKObjectManager* objectManager; @property (nonatomic, readonly) RKObjectMappingResult* result; @property (nonatomic, retain) RKObjectMapping* serializationMapping; @property (nonatomic, retain) NSString* serializationMIMEType; @property (nonatomic, retain) NSObject* sourceObject; @property (nonatomic, retain) NSObject* targetObject; - (void) setDelegate:(id<RKObjectLoaderDelegate>)delegate; + (id)loaderWithResourcePath:(NSString*)resourcePath objectManager: (RKObjectManager*)objectManager delegate:(id<RKObjectLoaderDelegate>)delegate; - (id)initWithResourcePath:(NSString*)resourcePath objectManager:(RKObjectManager*)objectManager delegate:(id<RKObjectLoaderDelegate>)delegate; - (void)handleResponseError; @end </code></pre> <p>.m file</p> <pre><code>#import "ASIHTTPObjectLoader.h" @interface ASIFormDataRequest (here) - (void) reportFailure; - (void) reportFinished; @end @implementation ASIHTTPObjectLoader @synthesize objectManager = _objectManager; @synthesize targetObject = _targetObject, objectMapping = _objectMapping; @synthesize result = _result; @synthesize serializationMapping = _serializationMapping; @synthesize serializationMIMEType = _serializationMIMEType; @synthesize sourceObject = _sourceObject; - (void) setDelegate:(id<RKObjectLoaderDelegate>)_delegate { [super setDelegate: _delegate]; } + (id)loaderWithResourcePath:(NSString*)resourcePath objectManager:(RKObjectManager*)objectManager delegate:(id<RKObjectLoaderDelegate>)_delegate { return [[[self alloc] initWithResourcePath:resourcePath objectManager:objectManager delegate:_delegate] autorelease]; } - (id)initWithResourcePath:(NSString*)resourcePath objectManager:(RKObjectManager*)objectManager delegate:(id<RKObjectLoaderDelegate>)_delegate { self = [super initWithURL: [objectManager.client URLForResourcePath: resourcePath]]; if ( self ) { self.delegate = _delegate; _objectManager = objectManager; } return self; } - (void)dealloc { // Weak reference _objectManager = nil; [_sourceObject release]; _sourceObject = nil; [_targetObject release]; _targetObject = nil; [_objectMapping release]; _objectMapping = nil; [_result release]; _result = nil; [_serializationMIMEType release]; [_serializationMapping release]; [super dealloc]; } - (void) reset { [_result release]; _result = nil; } - (void)finalizeLoad:(BOOL)successful error:(NSError*)_error { //_isLoading = NO; if (successful) { //_isLoaded = YES; if ([self.delegate respondsToSelector:@selector(objectLoaderDidFinishLoading:)]) { [self.delegate performSelectorOnMainThread:@selector(objectLoaderDidFinishLoading:) withObject:self waitUntilDone:YES]; } [super reportFinished]; /* NSDictionary* userInfo = [NSDictionary dictionaryWithObject:_response forKey:RKRequestDidLoadResponseNotificationUserInfoResponseKey]; [[NSNotificationCenter defaultCenter] postNotificationName:RKRequestDidLoadResponseNotification object:self userInfo:userInfo]; */ } else { NSDictionary* _userInfo = [NSDictionary dictionaryWithObject:(_error ? _error : (NSError*)[NSNull null]) forKey:RKRequestDidFailWithErrorNotificationUserInfoErrorKey]; [[NSNotificationCenter defaultCenter] postNotificationName:RKRequestDidFailWithErrorNotification object:self userInfo:_userInfo]; } } // Invoked on the main thread. Inform the delegate. - (void)informDelegateOfObjectLoadWithResultDictionary:(NSDictionary*)resultDictionary { NSAssert([NSThread isMainThread], @"RKObjectLoaderDelegate callbacks must occur on the main thread"); RKObjectMappingResult* result = [RKObjectMappingResult mappingResultWithDictionary:resultDictionary]; if ([self.delegate respondsToSelector:@selector(objectLoader:didLoadObjectDictionary:)]) { [self.delegate objectLoader: (RKObjectLoader*)self didLoadObjectDictionary:[result asDictionary]]; } if ([self.delegate respondsToSelector:@selector(objectLoader:didLoadObjects:)]) { [self.delegate objectLoader: (RKObjectLoader*)self didLoadObjects:[result asCollection]]; } if ([self.delegate respondsToSelector:@selector(objectLoader:didLoadObject:)]) { [self.delegate objectLoader: (RKObjectLoader*)self didLoadObject:[result asObject]]; } [self finalizeLoad:YES error:nil]; } #pragma mark - Subclass Hooks /** Overloaded by ASIHTTPManagedObjectLoader to serialize/deserialize managed objects at thread boundaries. @protected */ - (void)processMappingResult:(RKObjectMappingResult*)result { NSAssert(isSynchronous || ![NSThread isMainThread], @"Mapping result processing should occur on a background thread"); [self performSelectorOnMainThread:@selector(informDelegateOfObjectLoadWithResultDictionary:) withObject:[result asDictionary] waitUntilDone:YES]; } #pragma mark - Response Object Mapping - (RKObjectMappingResult*)mapResponseWithMappingProvider:(RKObjectMappingProvider*)mappingProvider toObject:(id)targetObject error:(NSError**)_error { NSString* MIMEType = [[self responseHeaders] objectForKey: @"Content-Type"]; id<RKParser> parser = [[RKParserRegistry sharedRegistry] parserForMIMEType: MIMEType]; NSAssert1(parser, @"Cannot perform object load without a parser for MIME Type '%@'", MIMEType); // Check that there is actually content in the response body for mapping. It is possible to get back a 200 response // with the appropriate MIME Type with no content (such as for a successful PUT or DELETE). Make sure we don't generate an error // in these cases id bodyAsString = [self responseString]; if (bodyAsString == nil || [[bodyAsString stringByTrimmingCharactersInSet:[NSCharacterSet whitespaceCharacterSet]] length] == 0) { RKLogDebug(@"Mapping attempted on empty response body..."); if (self.targetObject) { return [RKObjectMappingResult mappingResultWithDictionary:[NSDictionary dictionaryWithObject:self.targetObject forKey:@""]]; } return [RKObjectMappingResult mappingResultWithDictionary:[NSDictionary dictionary]]; } id parsedData = [parser objectFromString:bodyAsString error:_error]; if (parsedData == nil && _error) { return nil; } // Allow the delegate to manipulate the data if ([self.delegate respondsToSelector:@selector(objectLoader:willMapData:)]) { parsedData = [[parsedData mutableCopy] autorelease]; [self.delegate objectLoader: (RKObjectLoader*)self willMapData:&parsedData]; } RKObjectMapper* mapper = [RKObjectMapper mapperWithObject:parsedData mappingProvider:mappingProvider]; mapper.targetObject = targetObject; mapper.delegate = self; RKObjectMappingResult* result = [mapper performMapping]; // Log any mapping errors if (mapper.errorCount > 0) { RKLogError(@"Encountered errors during mapping: %@", [[mapper.errors valueForKey:@"localizedDescription"] componentsJoinedByString:@", "]); } // The object mapper will return a nil result if mapping failed if (nil == result) { // TODO: Construct a composite error that wraps up all the other errors. Should probably make it performMapping:&error when we have this? if (_error) *_error = [mapper.errors lastObject]; return nil; } return result; } - (RKObjectMappingResult*)performMapping:(NSError**)_error { NSAssert( isSynchronous || ![NSThread isMainThread], @"Mapping should occur on a background thread"); RKObjectMappingProvider* mappingProvider; if (self.objectMapping) { NSString* rootKeyPath = self.objectMapping.rootKeyPath ? self.objectMapping.rootKeyPath : @""; RKLogDebug(@"Found directly configured object mapping, creating temporary mapping provider for keyPath %@", rootKeyPath); mappingProvider = [[RKObjectMappingProvider new] autorelease]; [mappingProvider setMapping:self.objectMapping forKeyPath:rootKeyPath]; } else { RKLogDebug(@"No object mapping provider, using mapping provider from parent object manager to perform KVC mapping"); mappingProvider = self.objectManager.mappingProvider; } return [self mapResponseWithMappingProvider:mappingProvider toObject:self.targetObject error:_error]; } - (void)performMappingOnBackgroundThread { NSAutoreleasePool* pool = [[NSAutoreleasePool alloc] init]; NSError* _error = nil; _result = [[self performMapping:&_error] retain]; NSAssert(_result || _error, @"Expected performMapping to return a mapping result or an error."); if (self.result) { [self processMappingResult:self.result]; } else if (_error) { [self failWithError: _error]; } [pool drain]; } - (BOOL)canParseMIMEType:(NSString*)MIMEType { if ([[RKParserRegistry sharedRegistry] parserForMIMEType: MIMEType]) { return YES; } RKLogWarning(@"Unable to find parser for MIME Type '%@'", MIMEType); return NO; } - (BOOL)isResponseMappable { if ([self responseStatusCode] == 503) { [[NSNotificationCenter defaultCenter] postNotificationName:RKServiceDidBecomeUnavailableNotification object:self]; } NSString* MIMEType = [[self responseHeaders] objectForKey: @"Content-Type"]; if ( error ) { [self.delegate objectLoader: (RKObjectLoader*)self didFailWithError: error]; [self finalizeLoad:NO error: error]; return NO; } else if ([self responseStatusCode] == 204) { // The No Content (204) response will never have a message body or a MIME Type. Invoke the delegate with self [self informDelegateOfObjectLoadWithResultDictionary:[NSDictionary dictionaryWithObject:self forKey:@""]]; return NO; } else if (NO == [self canParseMIMEType: MIMEType]) { // We can't parse the response, it's unmappable regardless of the status code RKLogWarning(@"Encountered unexpected response with status code: %ld (MIME Type: %@)", (long) [self responseStatusCode], MIMEType); NSError* _error = [NSError errorWithDomain:RKRestKitErrorDomain code:RKObjectLoaderUnexpectedResponseError userInfo:nil]; if ([self.delegate respondsToSelector:@selector(objectLoaderDidLoadUnexpectedResponse:)]) { [self.delegate objectLoaderDidLoadUnexpectedResponse: (RKObjectLoader*)self]; } else { [self.delegate objectLoader: (RKObjectLoader*)self didFailWithError: _error]; } // NOTE: We skip didFailLoadWithError: here so that we don't send the delegate // conflicting messages around unexpected response and failure with error [self finalizeLoad:NO error:_error]; return NO; } else if (([self responseStatusCode] >= 400 && [self responseStatusCode] < 500) || ([self responseStatusCode] >= 500 && [self responseStatusCode] < 600) ) { // This is an error and we can map the MIME Type of the response [self handleResponseError]; return NO; } return YES; } - (void)handleResponseError { // Since we are mapping what we know to be an error response, we don't want to map the result back onto our // target object NSError* _error = nil; RKObjectMappingResult* result = [self mapResponseWithMappingProvider:self.objectManager.mappingProvider toObject:nil error:&_error]; if (result) { _error = [result asError]; } else { RKLogError(@"Encountered an error while attempting to map server side errors from payload: %@", [_error localizedDescription]); } [self.delegate objectLoader: (RKObjectLoader*)self didFailWithError:_error]; [self finalizeLoad:NO error:_error]; } #pragma mark - RKRequest & RKRequestDelegate methods - (void) reportFailure { [self.delegate objectLoader: (RKObjectLoader*)self didFailWithError:error]; [super reportFailure]; } - (void)reportFinished { NSAssert([NSThread isMainThread], @"RKObjectLoaderDelegate callbacks must occur on the main thread"); if ([self isResponseMappable]) { // Determine if we are synchronous here or not. if (isSynchronous) { NSError* _error = nil; _result = [[self performMapping:&_error] retain]; if (self.result) { [self processMappingResult:self.result]; } else { [self performSelectorInBackground:@selector(failWithError:) withObject:_error]; } [super reportFinished]; } else { [self performSelectorInBackground:@selector(performMappingOnBackgroundThread) withObject:nil]; } } } </code></pre>

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