In my app I use Restkit to map the JSON response into core data. I use - addFetchRequestBlock - so that restkit will cleanup orphaned objects.
// Cleanup of orphaned objects
[[RKObjectManager sharedManager] addFetchRequestBlock:^NSFetchRequest *(NSURL *URL) {
// Value returned from the relativePath
RKPathMatcher *pathMatcher = [RKPathMatcher pathMatcherWithPattern:#"/filesystem/v1/folder/:folderId"];
NSDictionary *argsDict = nil;
BOOL match = [pathMatcher matchesPath:[URL relativePath] tokenizeQueryStrings:NO parsedArguments:&argsDict];
NSString *folderID;
if (match)
{
NSFetchRequest *fetchRequest = [NSFetchRequest fetchRequestWithEntityName:#"ADStorageEntity"];
// Get the folder ID
folderID = [argsDict objectForKey:#"folderId"];
// Setup the fetchRequest
fetchRequest.predicate = [NSPredicate predicateWithFormat:#"parent = %#", #([folderID integerValue])]; // NOTE: Coerced from string to number
return fetchRequest;
}
return nil;
}];
All works well, but if I have an auth error 401
File List Request Failed with Error: Error Domain=org.restkit.RestKit.ErrorDomain Code=-1011 "Loaded an unprocessable error response (401)
all the managed objects in the "/:folderId" are treated as orphaned objects and gets deleted.
Is there a way to prevent this behaviour and not perform an orphaned objects cleanup?
EDIT -
Seems I was mapping the error
RKObjectMapping *errorMapping = [RKObjectMapping mappingForClass:[RKErrorMessage class]];
[errorMapping addPropertyMapping:[RKAttributeMapping attributeMappingFromKeyPath:#"error.code" toKeyPath:#"code"]];
[errorMapping addPropertyMapping:[RKAttributeMapping attributeMappingFromKeyPath:#"error.message" toKeyPath:#"message"]];
[errorMapping addPropertyMapping:[RKAttributeMapping attributeMappingFromKeyPath:#"error.description" toKeyPath:#"description"]];
RKResponseDescriptor *errorDescriptor = [RKResponseDescriptor responseDescriptorWithMapping:errorMapping method:RKRequestMethodAny pathPattern:nil keyPath:#"error" statusCodes:RKStatusCodeIndexSetForClass(RKStatusCodeClassClientError)];
[objectManager addResponseDescriptorsFromArray:#[errorDescriptor]];
after deleting the error mapping, the Fetch Request Block was not called
Fetch request blocks are only used on successful mappings, if the 401 raises an error then nothing should be deleted - if you don't have a mapping for it.
RKStatusCodeIndexSetForClass(RKStatusCodeClassClientError) covers all of the codes in the 4xx range. You don't need to use that. If you want to ignore the 401 response from the mapping then you can create an index set containing only 400 (or 400, 402, etc as required).
Related
I'm using the code below to post a managedObject. From the server, I'm not getting anything back, except 200, so there is no mapping for response object.
[self.objectManager postObject:invitation path:#"/path" parameters:nil success:^(RKObjectRequestOperation *operation, RKMappingResult *mappingResult) {
NSLog(#"success");
} failure:^(RKObjectRequestOperation *operation, NSError *error) {
NSLog(#"Failure");
}];
Is there a dummy format I can use for RKResponseDescriptor ?
RKResponseDescriptor *responseDescriptor = nil; //causes a crash
There is no 'dummy' RKResponseDescriptor instance, you must explicitly define what you want RestKit to do with the response data.
Your response descriptor can be partial, so it just maps one field to prove things are working.
Or, you could use a dynamic mapping to read the keys in the incoming data and create a mapping to NSMutableDictionary which includes all of the keys.
Both of these things are only really useful for testing, but may assist you.
If the response actually has no body data and you just want to monitor for success then you can either use AFNetworking instead, or create the response descriptor with a mapping to NSMutableDictionary and with no keys. RestKit should pick that up and it should act as a 'dummy' for your purposes. It will create a dictionary instance that is never used, but you can just ignore that.
RKObjectMapping *mapping = [RKObjectMapping mappingForClass:[NSMutableDictionary class]];
RKResponseDescriptor *responseDescriptor = [RKResponseDescriptor responseDescriptorWithMapping:mapping
method:RKRequestMethodPOST
pathPattern:#"/path"
keyPath:nil
statusCodes:[self statusCodeSuccess]];
I have a pretty weird problem. I'm using coredata to save notes. I can access/save/edit all the attributes of the "Notes" entity, besides one : category.
-(void)editCategory {
NSFetchRequest *request = [[NSFetchRequest alloc]init];
NSEntityDescription *categRequest = [NSEntityDescription entityForName:#"Notes" inManagedObjectContext:_managedObjectContext];
request.predicate = [NSPredicate predicateWithFormat:#"text = %#", noteToEdit];
[request setEntity:categRequest];
//Error handling
NSError *error = nil;
NSMutableArray *mutableFetchResults = [[_managedObjectContext executeFetchRequest:request error:&error]mutableCopy];
if (mutableFetchResults == nil) {
NSLog(#"Error happened : %#", error);
}
Notes *editMe = [mutableFetchResults objectAtIndex:0];
[editMe setCategory:editCategoryText];
NSLog(#"Category from pickerview : %#", editCategoryText);
if (![_managedObjectContext save:&error]) {
NSLog(#"couldnt save : %#", error);
}
}
This line :
[editMe setCategory:editCategoryText];
is crashing. editCategoryText is a string, as the category attribute. The weird thing is that I'm using the exact same piece of code to change the title attribute, and I don't have any problem.
Log file :
2013-11-07 15:49:20.286 Simple Notes 1[16511:a0b] -[__NSCFString managedObjectContext]: unrecognized selector sent to instance 0x8dccc30
2013-11-07 15:49:20.293 Simple Notes 1[16511:a0b] *** Terminating app due to uncaught exception 'NSInvalidArgumentException', reason: '-[__NSCFString managedObjectContext]: unrecognized selector sent to instance 0x8dccc30'
Do you have any idea why this attribute is behaving differently from the others ? Thank you.
Not at a computer so can't test this but:
Get rid of the mutableCopy. executeFetchRequest returns autoreleased objects, which you are then trying to copy, this turns into a garbage pointer, which happens to end up pointing to a string.
Actually it seems like it was a core data bug, I solved it by deleting my app in the simulator, deleting the core data model in xcode, built it again and performed a clean.
I have created few entities in context for saving it in db using
AppCalendarEntity *appCalendar = [AppCalendarEntity getInstanceWithManagedDocument:manageDocument];
After adding a few entities I execute flowing fetch request
NSFetchRequest *requestToSeeIfCalendarWithIdExist = [NSFetchRequest fetchRequestWithEntityName:#"AppCalendarEntity"];
NSArray *result = [managedDocument.managedObjectContext executeFetchRequest:requestToSeeIfCalendarWithIdExist error:&InternalError] ;
It returns me the result including only the entities I have added in context using first command and NOT the entries already saved in database. I have made sure that at this stage the document state is UIDocumentStateNormal.
When I add this line to already open document (UIDocumentStateNormal) it returns me the expected result, i.e. it fetch results from db as well as memory context which has not yet been saved to db.
[managedDocument openWithCompletionHandler:^(BOOL success)
{
NSFetchRequest *requestToSeeIfCalendarWithIdExist = [NSFetchRequest fetchRequestWithEntityName:#"AppCalendarEntity"];
NSArray *result = [managedDocument.managedObjectContext executeFetchRequest:requestToSeeIfCalendarWithIdExist error:&InternalError] ;
}
My question is
1- I expect that the result of query should be the same in both cases. Why it is not so in the above case.
2- To me if document state is UIDocumentStateNormal I should not be calling "openWithCompletionHandler" in context to open the document. In this particular scenario what difference it is making in NSFetchRequest which gives me the desired result after adding this.
Please let me know if I'm getting wrong
Here is the complete code
This is the complete code of the function
+ (void ) saveCalendarArrayInDbIfItAlreadyDoesNotExist : (NSArray*) appCalendarArray managedDocument: (UIManagedDocument*) managedDocument completionBlock : ( void(^) (NSArray* ObjectSavedSuccesfully, NSError *InternalError)) handler
{
// i dont know why i have to do it :( if i dont add openWithCompletionHandler my query doesnt fetch result from db rather just do query in-memory context and not db
[managedDocument openWithCompletionHandler:^(BOOL success)
{
void (^completionHandler)(NSArray* , NSError* );
completionHandler = [handler copy ];
NSError *error = nil;
NSMutableArray *array = [[NSMutableArray alloc] init];
for (id appCalendar in appCalendarArray) {
if([appCalendar isKindOfClass:[AppCalendarEntity class]])
{
AppCalendarEntity *appCalendarEntity = (AppCalendarEntity*) appCalendar;
NSFetchRequest *requestToSeeIfCalendarWithIdExist = [NSFetchRequest fetchRequestWithEntityName:#"MyEntity"];
requestToSeeIfCalendarWithIdExist.predicate = [NSPredicate predicateWithFormat:#"identifier = %#", appCalendarEntity.identifier];
NSError *InternalError = nil;
[requestToSeeIfCalendarWithIdExist setShouldRefreshRefetchedObjects:YES];
NSArray *result = [managedDocument.managedObjectContext executeFetchRequest:requestToSeeIfCalendarWithIdExist error:&InternalError] ;
// "result" is different when we encapsulate it in openWithCompletionHandler and when we don't…….MY PROBLEM
if(result == nil)
{
// return error
}
// 1 object always return that depict the in memory(context) object we created but not saved. I expect it should be zero because no object has yet been saved to database..
else if(result.count > 1)
{
[managedDocument.managedObjectContext deleteObject:appCalendar];
}
else
{
[array addObject:appCalendarEntity];
}
}
else
{
// error handling
}
}
if (error != nil)
{
completionHandler (nil, error);
return;
}
// saving all the objects
[ managedDocument updateChangeCount:UIDocumentChangeDone ];
}
When using UIManagedDocument, you do not call save on the MOC because it implements auto-save. however, it needs to be told that an auto-save should take place at some point in the future.
Get rid of that call to openWithCompletionHandler in that function (I know it was just there for purposes of debugging this problem).
Replace
[managedDocument.managedObjectContext save:&InternalError ]
with
[managedDocument updateChangeCount:UIDocumentChangeDone];
This will notify the document that it can now be saved.
EDIT
First, I think you should get rid of the debugging hacks. You can add NSLog or NSAssert, but the rest of that stuff just makes it hard to tell why you want, and confuses the real issue.
Second, what is your real goal here? I can see the name of the method, and I can see the code, but they do not match.
There is so much "cruft" here, it is hard to understand your problem. I am going to repost your code, along with an edit to remove the "open" stuff, and annotate it with questions as code comments.
Hopefully, this change will help you solve your problem.
// First, the method name seems to indicate that some objects will be added
// to the database. however, the only database work in this method is removal.
// I don't get it.
+ (void ) saveCalendarArrayInDbIfItAlreadyDoesNotExist : (NSArray*) appCalendarArray managedDocument: (UIManagedDocument*) managedDocument
{
NSError *error = nil;
NSMutableArray *array = [[NSMutableArray alloc] init];
for (id appCalendar in appCalendarArray) {
if([appCalendar isKindOfClass:[AppCalendarEntity class]]) {
// OK, we are filtering the array of objects. We are only interested in
// objects of type AppCalendarEntity, and are going to use its identity
// property to look for objects of type MyEntity.
// What is the relationship between AppCalendarEntity and MyEntity?
AppCalendarEntity *appCalendarEntity = (AppCalendarEntity*) appCalendar;
NSFetchRequest *requestToSeeIfCalendarWithIdExist = [NSFetchRequest fetchRequestWithEntityName:#"MyEntity"];
requestToSeeIfCalendarWithIdExist.predicate = [NSPredicate predicateWithFormat:#"identifier = %#", appCalendarEntity.identifier];
NSError *InternalError = nil;
[requestToSeeIfCalendarWithIdExist setShouldRefreshRefetchedObjects:YES];
NSArray *result = [managedDocument.managedObjectContext executeFetchRequest:requestToSeeIfCalendarWithIdExist error:&InternalError];
// OK, now we just got a result from searching for a MyEntity, where
// its identifier is the same as the appCalendarEntity.
if(result == nil)
{
// return error
}
// 1 object always return that depict the in memory(context) object we created but not saved. I expect it should be zero because no object has yet been saved to database..
else if(result.count > 1)
{
// I am extremely confused by this code. First, why are you
// checking for more than 1 object? The method name indicates
// you are going to insert something. Furthermore, you are only
// deleting one object. How many do you expect? Also, why are
// you deleting an appCalendar? You were searching for a MyEntity.
// If an appCalendar is a MyEntity, then that's terrible naming.
// Furthermore, it would explain why you are finding it...
// because you create entities by inserting them in a MOC to
// begin with!
[managedDocument.managedObjectContext deleteObject:appCalendar];
}
else
{
// Even more confusion. You are adding this object to an internal
// array, not the database. Furthermore, you are doing it if there
// are either 0 or 1 MyEntity objects in the database with matching
// identifier.
[array addObject:appCalendarEntity];
}
}
}
// saving all the objects
// OK - but the only thing being saved are the ones you deleted...
[ managedDocument updateChangeCount:UIDocumentChangeDone ];
}
Finally, if my hunch is correct, and the calendar objects are actually MyEntity objects, they are already in the MOC - because that's how they get created. When you do a fetch, you can force the search to ignore pending changes (as noted in one of my previous comments) and only accept saved changes.
If you want to ignore pending changes,
fetchRequest.includesPendingChanges = NO;
#Jody Problem has been resolved and thank you for giving time to this question.
First let me address your confusions
1- Yes function is intended to save in the database and it is a helping function. The parameter "appCalendarArray" being passed to this function consist of entities that has already been created in context. I intentionally eliminated the logic since it involves communicating with external apis, parsing json etc etc. The code required for inserting entities in context has already been included in first part of the question.
AppCalendarEntity *appCalendar = [AppCalendarEntity getInstanceWithManagedDocument:manageDocument];
2- I eliminate the entities from context which has been constructed but not yet saved from context, based upon a column in database that should be unique. If we have identifier for object already in database, we do not want to resave it. So, I simply delete it from context. This function works as expected, entities are not re-saved in database. The last line do save the objects that are left in context if any. Most of the time there are a lot.
3- Sorry for mistyping AppCalendarEntity and MyEntity are the same.
Solution
I have added this flag fetchRequest.includesPendingChanges = NO; , delete db, restarted Xcode and it started working. Thank you for your persistence
I have an Entity with some Attribute. I have my tabes already populates(SQLite table)
In one Attribute (i'll call Attribute1) i have a bool value, changing during use of my app.
How can i return the count of my Entities with Attribute1 value YES?
I've already read "Core data Tutorial" and "Predicate Programing Guide" but i don't understand how to proceed..
NSPredicate *predicate= [NSPredicate predicateWithFormat:#"Attribute1 == %#",[NSNumber numberWithBool:YES]];
I've tried with this, and then? it seems not working..
The best bet is to use the countForFetchRequest method. Set up your predicate and fetch request, but instead of doing the actual fetch, execute countForFetchRequest as follows:
NSFetchRequest *request = [[[NSFetchRequest alloc] init] autorelease];
NSPredicate *predicate =
[NSPredicate predicateWithFormat:#"Attribute1 == %#",
[NSNumber numberWithBool:YES]];
[request setPredicate:predicate];
NSUInteger count = [myManagedObjectContext countForFetchRequest:request error:nil];
You can find more info in the Apple API Docs:
countForFetchRequest:error:
Returns the number of objects a given fetch request would have returned if it had been passed to executeFetchRequest:error:.
(NSUInteger)countForFetchRequest:(NSFetchRequest )request error:(NSError *)error
Parameters
request
A fetch request that specifies the search criteria for the fetch.
error
If there is a problem executing the fetch, upon return contains an instance of NSError that describes the problem.
Return Value
The number of objects a given fetch request would have returned if it had been passed to executeFetchRequest:error:, or NSNotFound if an error occurs.
Availability
Available in iOS 3.0 and later.
Declared In
NSManagedObjectContext.h
I am wanting to set up a basic relationship with two entities in Core Data, but the relationship is either not saving, or is not working properly and I'm not sure why.
The two entities are Character and Avatar, its a one-to-one relationship. A character can have 1 avatar. Technically, it should be a "one avatar can be owned by many characters", but I'll deal with that later.
I want to add characters and assign them an avatar.
There are already 10 avatars in Core Data and 1 character, both of which I've verified via the Terminal and SQLite.
The problem is, I'm having troubling "finding an avatar by a name and then saving the relationship to a character".
So far,
I set up a fetch request called: "frqAvatarWithName" where the Predicate has the following structure:
[quote]
name == $AVATAR_NAME
[/quote]
This is so: I can find an avatar with a certain name; and then I can create a relationship with a character.
Issue 1: It gets to execute the query but then never displays how many records there are.
I get a EXC_BAD_ACCESS error in debug mode and I have traced it back to the fetch request template handling -- so, this must be in error or I have done it wrong.
Issue 2: I am not sure if I am even setting up this "basic" relationship up properly.
[code]
// This code is meant to find an avatar with a certain name and then save the relationship
// between a character and said avatar.
// This is my app delegate file for the moment
// All the files are present, and I have deleted/recreated the app various times
-(void)characterMaker
{
NSLog(#"Inside characterMaker...");
NSError *error = nil;
NSManagedObjectContext *context = [self managedObjectContext];
NSManagedObjectModel *model = [self managedObjectModel];
// Find an avatar with a specific name
NSString *nameToFind = #"avt_player_1";
// Use a Fetch request template
NSDictionary *subs = [NSDictionary dictionaryWithObjectsAndKeys:nameToFind, #"AVATAR_NAME", nil];
NSFetchRequest *fetchRequest = [model fetchRequestFromTemplateWithName:#"frqAvatarWithName"
substitutionVariables:subs];
// Set the entity to use
NSEntityDescription *entity = [NSEntityDescription entityForName:#"Avatar"
inManagedObjectContext:context];
[fetchRequest setEntity:entity];
// Execute the query (it never even reaches this point)
NSArray *fetchedObjects = [context executeFetchRequest:fetchRequest error:&error];
if (fetchedObjects == nil) {
// Handle the error
NSLog(#"Error -- %#", [error localizedDescription]);
abort();
}
NSLog(#"Found %# records", [fetchedObjects count]);
// Print out avatar names
for (Avatar *a in fetchedObjects)
{
NSLog(#"Name = %#", [a valueForKey:#"name"]);
}
// This is where I would use `a` and store it in a character entity, and thus create the relationship
[/code]
I gave up on this and did the whole project with the FMDatabase project and SQLite; I've been able to resolve the problem this way.
Thread closed.