I use getEntityGraph extension and it works fine except in the following scenario:
add a new entity
don't save it and call setDeleted on the entity
call getEntityGraph by passing the entity and a np collection as parameters
When makePathSegmentFn is called, it crashes on this line :
grps.forEach(function(grp) {
vals = vals.concat(grp._entities.filter(function (en) {
return en.getProperty(fkName) === keyValue;
}));
});
en is null so it raises an exception. I've worked around the problem by checking if en is null and every seems to work fine. But perhaps that should be done in the original code if it's a bug ? Note that only one entity is null amongst all the entities in the np collection. I guess that's the one that was deleted, but can't tell for sure.
Update 29 April 2014
OK ... I get it now. You're talking about a deleted child entity, not a detached root entity.
Thanks for identifying this bug. I added a test for this scenario to DocCode, then fixed the bug. Both changes pushed to github. They will appear in the next official release. You can get the current getEntityGraph.js from github right now.
Original answer
I can't duplicate the particular failure you describe ... because getEntityGraph throws long before it gets to the makePathSegmentFn ... as it should do!
getEntityGraph is supposed to throw an exception (e.g., "'getEntityGraph' root[0] is a detached entity") when any of the root entities passed in are 'Detached'.
When you create a new entity and immediately delete it (without saving it first), its state changes from 'Added' to 'Detached'; it is no longer an entity in cache. That is expected behavior (see "EntityState transitions" in the "Inside the Entity" documentation topic). That's what happens when I follow your repro steps exactly.
Please provide a jsFiddle or plunker that demonstrates the error.
Related
private void doSomething(someProcessModel process){
CustomerModel customer = process.getCustomerModel();
customer.getFoos().stream()
.filter(foo -> foo.getCountryCode().equals(process.getCountryCode()))
.findFirst()
.ifPresent(foo -> {
if(foo.getSomeNumber() == null){
foo.setSomeNumber("1234567");
modelService.save(foo);
}
});
}
As seen in the code snippet above, I have a 'CustomerModel' that has an attribute 'Foos'. It's a one-to-many relationship. As you can see I have done some filtering and in the end, I want to update the value of 'someNumber' attribute of 'Foo' if it is null. I've confirmed that everything is working as the "someNumber" attribute's value is updated during the debugging. It doesn't save at all as I have done my checking in the HMC. I have also validated that the Interceptor doesn't have any condition that would throw an error. There is nothing being shown in the log either.
I am wondering is it a legal approach to do the "modelService.save()' inside the 'ifPresent()' method? What could be the possible issue here?
I have found the root cause now as I have face the same issue again.
Context to my original question
To give more context to my original question, the #doSomething method resides in a Hybris Business Process action class and I have ended the action prematurely while I am debugging it (by stopping the debugging) once the #doSomething method is ran.
Root cause
The mentioned problem happened when I was debugging the action class. I assumed that the ModelService#save will persist the current state of the business process once it has been ran. However, the Hybris OOTB business process will do a rollback if there is any error (and I believe it was caused by me stopping the debugging half-way).
SAP Commerce Documentation:
All actions are performed inside their own transaction. This means that changes made inside the action bean run method are rolled back in case of an error.
Solution
Let the action runs completely!
Good to know
Based on the SAP Documentation and this blog post, there will be times that we will need to bypass a business process rollback even though there is an exception being thrown and there are ways to achieve that. More info can be found in this SAP Commerce Documentation and the mentioned blog post.
However, in some circumstances it may be required to let a business exception reach the outside but also commit the transaction and deal with the exception outside. Therefore, it is possible to make the task engine not roll back the changes made during a task which failed.
You have to be cautious with a list in models as they are immutable, you have to set the whole new list. Also you called save only on a particular model, which changes its Jalo reference, that's why your list is not updated. Mutating stream and collecting it in the end will create new list that's why you can stream over the list directly from the model.
private void doSomething(someProcessModel process){
CustomerModel customer = process.getCustomerModel();
ArrayList<FooModel> foos = doSomethingOnFoos(customer.getFoos());
customer.setFoos(foos);
modelService.saveAll(foos, customer);
}
//compare the value you know exists with something that might be NULL as equals can handle that, but not the other way around
private ArrayList<FooModel> doSomethingOnFoos(ArrayList<FooModel> fooList) {
return fooList.stream()
.filter(Objects::nonNull)
.filter(foo -> process.getCountryCode().equals(foo.getCountryCode()))
.filter(foo -> Objects.isNull(foo.getSomeNumber()))
.map(foo -> foo.setSomeNumber(1234))
.collect(toList());
}
I'm using Wards excellent example of implementing many-to-many with breeze. (i'm going off the plunk in his post, cant link to it from here dont know why)
Everything is working great, changes are always saved to database correctly.
I am using 2 different (BreezeJS) EntityManagers: one for edits, and one as my "master". On saving the editor Em to database, it then imports all changes into the master Em so it all stays in sync. This has been working wonderfully for all my other functions.
However, when saving the many-to-many mapping, for some reason any deleted mappings are not removed from the master Em. (When I add mappings they correctly show up in the master Em right away).
Do I need to take another step to get my master Em to remove imported detached entities?
(FYI, everything is saving correctly to server, if I do hard page refresh, all my entities show up correctly).
My code for deleting entity on editor Em:myEntity.entityAspect.setDeleted();
Function below will export changed entities from editor Em:
function exportToMasterAfterSavingSuccess(saveResult){
if(saveResult.entities)
masterEm.importEntities(manager.exportEntities(entities, false));
}
And the corresponding import function on master em:
function importEntities(entities){
var imported = manager.importEntities(entities,{ mergeStrategy: breeze.MergeStrategy.OverwriteChanges});
}
Thanks for uncovering a bug. One shouldn't be able to export or import a detached entity. In future, Breeze will throw if you attempt to do either.
Now I'll discuss your issue, your aims, and what I recommend that you do.
Update master EntityManager after saving deleted entities
As I understand it you maintain a masterEm which has only the saved state of entities. You make and save your changes in a separate editEm. You import entities that you will change into the editEm, make changes, save them, and (if the save is successful), you export the saved entities from editEm and import them back into masterEm. This is a common "sandbox editing" pattern.
Trouble arises when you delete an entity in editEm. After save, that entity is "Detached" in the editEm but it's still in an "Unchanged" state back in the masterEm. How do you communicate the fact that the entity is deleted and remove it from masterEm?
This dilemma exists independent of the "many-to-many" scenario that inspired your question.
I can see why your practice of importing the now-Detached entity from editEm to masterEm seemed to work. Doing that in v.1.5.3 caused the corresponding entity in masterEm to change to the "Detached" state ... which is what you wanted. The bug, as you saw it, was that the importEntities method didn't handle update of navigation properties properly when the imported entity is in a "Detached" state. You proposed teaching importEntities to "do the right thing" in that scenario.
What actually happened here is that you discovered a bug. You should never have been able to export a "Detached" entity and you shouldn't have been able to import one either. Breeze should have thrown an exception when you tried to export or import a "Detached" entity.
There are all kinds of reasons why asking an EntityManager to export/import "Detached" entities is a bad idea. I leave explication of those reasons for another day.
Rather than "solve" the problem of importing related "Detached" entities, we will throw an error.
This means that your partial solution will cease to work, leaving you apparently worse of than you are today. Fortunately, I have an alternative approach for you. I've written this utility function and tested it in DocCode:
function updateMasterWithSaveResult(masterEm, sourceEm, saveResult) {
var imports = [];
var deletes = [];
saveResult.entities.forEach(function(entity) {
if (entity.entityAspect.entityState.isDetached()) {
deletes.push(entity);
} else {
imports.push(entity);
}
});
var exported = sourceEm.exportEntities(imports, {
includeMetadata: false,
asString: false // as JSON
});
masterEm.importEntities(exported);
deletes.forEach(function(detached) {
var entity = masterEm.getEntityByKey(detached.entityAspect.getKey());
entity && entity.entityAspect.setDetached();
});
}
Updated documentation
I just added this to our "Cool Breeze" documentation almost verbatim.
Please try this with the latest released version of breeze (1.5.3). A very similar bug was fixed there.
And just to be clear, and export can never include 'detached' entities ( only 'deleted' ones). Detached entities are, by definition, no longer attached to an EntityManager so the EntityManager no longer knows anything about them.
I'm having the exact same issue. I'm not doing many-to-many but still doing edits/adds/deletes in a separate entityManager.
I can confirm that the export DOES include Detached entities, and on import into the master entityManager with MergeStrategy.OverwriteChanges, those entities do become detached.
However, the newly detached entities are still associated with any related entities.
Reattaching and detaching seems to get everything back in sync as far as I can tell:
var result = manager.importEntities(imports);
result.entities
.filter(function (entity) { return entity.entityAspect.entityState.isDetached(); })
.forEach(function (entity) { manager.attachEntity(entity); manager.detachEntity(entity); });
Breeze 1.5.3
Github issue with pull request:
https://github.com/Breeze/breeze.js/issues/75
I am using Entity Framework 4 (database-first approach) in my ASP.NET 4.0 Webforms app.
What I'm basically doing is fetching the entity to be edited from my ObjectContext, and displaying the fields the user should enter data into (or modify existing data) on a web form.
When time comes to store the data back, I'm reading out the values from the web form, building up a new Entity instance, and then I have a generic method called AddOrUpdate that detects whether this is a new entity (so it needs to insert it), or if it's an existing one (so it needs to update the existing data).
My method using the EntityKey and checks to see if the object context already knows about this object - very similar to what Cesar de la Torre of Microsoft shows here in his blog post:
public static void AddOrUpdate(ObjectContext context, EntityObject objectDetached)
{
if (objectDetached.EntityState == EntityState.Detached)
{
object currentEntityInDb = null;
if (context.TryGetObjectByKey(objectDetached.EntityKey, out currentEntityInDb))
{
// attach and update the existing entity
}
else
{
// insert new entity into entity set
context.AddObject(objectDetached.EntityKey.EntitySetName, objectDetached);
}
}
}
This worked just fine - for the longest time. But today, suddenly, out of the blue, I keep getting exceptions like this on the context.TryGetObjectByKey statement:
System.InvalidOperationException: Object mapping could not be found for Type with identity 'MyEntityType'
I cannot remember having changed anything in this core code at all - and the entity type is defined, the ID value that's stored in the EntityKey does indeed exist in the database... everything should be fine - but it keeps failing on me...
What on earth happened here??
I did find a few blog and forum posts on the topic, but none could really enlighten me or help me fix the issue. I must have messed up something - bad - but I really cannot see the forest for the trees - any hints?
Generally this sort of issue happens when EF cant find the assembly that has the type. With out seeing the full exception is difficult to figure out exactly but it seems your recent changes and the way you are using EF seems to be the cause.
EF ususally picks the type directly from the type itself when it has to access it using ObjectSet on the context. In the other cases where the type is not available from the context of the call it looks at the calling assembly and any dll's referenced by the calling assembly. Id it cant find it it throws the error message.
You can use the LoadFromAssembly method in the MetadataWorkspace of the context.
ObjectContext.MetadataWorkspace.LoadFromAssembly(assembly).
This way EF will know where to look for your types.
preface note: I'm just starting to learn Grails, so I'm sure there are many other problems and room for optimization.
I've got two domains, a parent (Collection) and child (Event), in a one-to-many mapping. I'm trying to code an integration test for the deletion of children. Prior to the code in question, I've successfully created a parent and three children. The point where I'm having problems is getting a single child in preparation to delete it. The first line of my sample code is only there because of my rudimentary attempt to troubleshoot.
// lines 95-100 of my EventIntegrationTests.groovy file
// delete a single event
assertEquals("2nd Event", event2.title) // passes
def foundEvent = Event.get(event2.id) // no apparent problems
assertEquals("2nd Event", foundEvent.title) // FAILS (line #98)
foundEvent.delete()
assertFalse Event.exists(foundEvent.id)
The error message I'm getting is:
Cannot get property 'title' on null object
java.lang.NullPointerException: Cannot get property 'title' on null object
at edu.learninggrails.EventIntegrationTests.testEventsDelete(EventIntegrationTests.groovy:98)
What should my next troubleshooting steps be? (Since the first assertEquals passes, event2 is clearly not null, so at this point I have no idea how to troubleshoot the failure of the second assertEquals.)
This is not evident from the code: did you persist event2 by calling save()? Get will try to retrieve it from the persistent storage (the in-memory database for example) and if the event wasn't saved, the retrieved instance will be null.
If you did save it, did the save go through OK? Calling event.save() will return false if there was something wrong while saving the item (like a validation error). Lastly, you might try calling event.save(flush:true) in case the Hibernate session doesn't handle this case as you might expect (I'm not entirely sure about this one, but it can't hurt to try).
Try to print or inspect the event2.id on line 97 and check if you actually have an id, if so check if you actually get an Event object on line 97.
I dont think you saved the parent and its children successfully. after you save, you should make sure that every object that was persisted has a non null id, in your test.
What you are seeing is you created the event2 with a title, but didnt save it. It passes the first assertion because you created it. When you do the get, null is returned because your save failed.
in general for DAO integration tests i do the following
Setup -- create all objects Ill use in the test.
Save -- assert that all ids on saved objects are NOT null.
Clear the hibernate session -- this is important because if you don't do it, objects can be in the session from the previous operations. In your real world scenario, you are probably going to start with a find, i.e. an empty session. In other words, you are not going to start with anything in the session. If you are you need to adjust this rule so that the session in the test, when you start the actual testing part, is the same as the session of the code in the wild
Load the objects on which you want to operate and do what you need to do.
I'm using LINQ to SQL in ASP.NET MVC. I wrote some new code to update Orders in our system, and as far as I can tell it's exactly like a hundred other similar pieces of code I've written (grab the object, update some fields, submit changes).
This time though, when I try to run the update, I get a "Row not found or changed" LINQ exception on this call stack:
System.Data.Linq.dll!System.Data.Linq.DataContext.SubmitChanges(System.Data.Linq.ConflictMode failureMode) + 0x14c bytes
System.Data.Linq.dll!System.Data.Linq.DataContext.SubmitChanges() + 0x14 bytes
If I just refresh the page after the exception, it just works with no issues.
How can I get it to work correctly the first time?
I've seen answers on the net relating to DateTime precision and Update checks, but nothing about the submission simply working the second time, not the first.
My code is basically like this:
Order order = myDataContext.Orders.SingleOrDefault(order.OrderID == orderID);
order.Field1 = true;
order.Boolean2 = true;
order.Double1 = 300.0;
myDataContext.SubmitChanges();
The issue turned out to be that I was changing a related table in between fetching the Order, editing, and saving it.
When the related table was changed, the Order table was indirectly changed because of the parent-child relationship. That caused the change checking validation to fail.
All I needed to do is pull all the related code (fetch, change, save) into one tight block, with no other code in-between. I'm not having any problems now.
Your code looks fine.
There must be something else in myDataContext that is causing the problem.
Where is myDataContext defined? I am guessing that there is some code in a if is postback block, or something similar, to cause the code that runs to take a different path.
Are you creating a new datacontext when rebinding (after calling SubmitChanges)?
You should never reuse a datacontext for selecting, after performing insert/update/delete actions with it.