Copy entities from one Breeze EntityManager to another EntityManager - breeze

This breeze documentation page has this sample for making a copy of an EntityManager:
function createManager() {
// same configuration; no entities in cache.
var manager = masterManager.createEmptyCopy();
// ... copy in some entities (e.g.,picklists) from masterManager
return manager;
}
I am not sure how I am supposed to do the "copy in some entities (e.g.,picklists) from masterManager" step.
I guess I could just go create the entities as if they are new. But they are not, they are picklist values that were queried from the database.
I thought about trying to use Export/Import, but that seems like it is intended for offline work and serializes all the values to string. (Which seems like it may not be as performant as what I would like.)
Is there "normal" way that everyone copies entities between EntityManagers?

Yes, you copy the entities by exporting and importing. For performance, you should specify
asString: false, to avoid string serialization overhead, and
includeMetadata: false, since createEmptyCopy() creates an EntityManager that already has metadata
So:
function createManager() {
// same configuration; no entities in cache.
var manager = masterManager.createEmptyCopy();
var entities = masterManager.exportEntities(null, { asString: false, includeMetadata: false });
manager.importEntities(entities);
return manager;
}

Related

How to delete tenant completely?

I'm developing a multitenant application and would like to have to option to remove a tenant. This however seems to be less trivial than one would assume.
My goal is to delete all references to the tenant everywhere in the database. I understand that Tenant is Soft-Delete, but I since I don't want my database to fill up with old meaningless data I've tried disabling the soft-delete filter.
Here is some code that I've tried:
using (_unitOfWorkManager.Current.DisableFilter(AbpDataFilters.SoftDelete))
{
await TenantRepository.DeleteAsync(x => x.Id == tenantId);
}
This did not work. The tenant is marked as "IsDeleted" but not removed.
Then I figured that maybe it has something to do with UnitOfWork so I made sure no UnitOfWork was active and then manually controlled it:
using (var unitOfWork = _unitOfWorkManager.Begin())
{
// the codeblock above went here
unitOfWork.Complete();
}
This did not work, same result. And this is just the AbpTenant table. I'm also trying to delete from all other tables. For example AbpSettings and AbpLanguages. It's very unclear to me how to do that at all - the "managers" doesn't contain any Delete functions.
I tried creating IRepository for these entities but it does not work. The error reads
The type Abo.Configuration.Setting cannot be used as a type parameter TEntity in the generic type or method IRepository. There is no implicit reference conversion from Abp.Configuration.Setting to Abo.Domain.Entities.IEntity.
That leaves me with the option to use the DataContext directly:
using (EntityFramework.MyDbContext db = new EntityFramework.MyDbContext())
{
List<PermissionSetting> perms = await db.Permissions.Where(x => x.TenantId == tenantId).ToListAsync();
for (int i=0; i<perms.Count(); i++)
{
db.Permissions.Remove(perms[i]);
}
// I also tried deleting them in bulk at first
// ((DbSet<PermissionSetting>)db.Permissions).RemoveRange(db.Permissions.Where(x => x.TenantId == tenantId));
await db.SaveChangesAsync();
}
I tried that with and without UnitOfWork.
But it simply does not get deleted from the database. I'm getting no errors or Exceptions.
Why does it not get deleted? How can I delete it? Surely it must be possible?
since I don't want my database to fill up with old meaningless data I've tried disabling the soft-delete filter.
From the question on Disable SoftDelete for AbpUserRole:
protected override void CancelDeletionForSoftDelete(EntityEntry entry)
{
if (IsSoftDeleteFilterEnabled)
{
base.CancelDeletionForSoftDelete(entry);
}
}
The type Abo.Configuration.Setting cannot be used as a type parameter TEntity in the generic type or method IRepository. There is no implicit reference conversion from Abp.Configuration.Setting to Abo.Domain.Entities.IEntity.
Inject IRepository<Setting, long> instead of IRepository<Setting>.
That leaves me with the option to use the DataContext directly
...
But it simply does not get deleted from the database. I'm getting no errors or Exceptions.
From the documentation on Data Filters:
using (_unitOfWorkManager.Current.DisableFilter(AbpDataFilters.MayHaveTenant))
{
using (var db = new ...)
{
// ...
}
}
That said, there is no way to easily delete related tenant data completely. Consider writing SQL.

Breeze 1-To-Many Unidirectional Navigation Property not Populated

Breeze Version: 1.5.3
I'm experiencing something similiar to some older questions on SO but it seems like this "bug" is reoccurring:
I have a 1-To-Many unidirectional navigation property which is not populated. I have checked the metadata and the response from the server. I've even debugged into breeze and the node (or rawEntity) seems to be perfect.
I've tried to track it down and came to the conclusion, that it happens, because no "inverse"-Property is found for my Navigation Property and the mergeRelatedEntities-Function returning without updating the target Entity:
function mergeRelatedEntities(mc, navigationProperty, targetEntity, rawEntity) {
var relatedEntities = mergeRelatedEntitiesCore(mc, rawEntity, navigationProperty);
if (relatedEntities == null) return;
var inverseProperty = navigationProperty.inverse;
if (!inverseProperty) return;
var originalRelatedEntities = targetEntity.getProperty(navigationProperty.name);
originalRelatedEntities.wasLoaded = true;
relatedEntities.forEach(function (relatedEntity) {
if (typeof relatedEntity === 'function') {
mc.deferredFns.push(function () {
relatedEntity = relatedEntity();
updateRelatedEntityInCollection(relatedEntity, originalRelatedEntities, targetEntity, inverseProperty);
});
} else {
updateRelatedEntityInCollection(relatedEntity, originalRelatedEntities, targetEntity, inverseProperty);
}
});
}
Older Posts:
Non scalar navigation properties are not populating with "nodb" conception
and
Breeze (1.4.5) unidirectional one-to-many: navigation collection not populated
Edited 11. May 2015
Okay I start to understand what Ward meant with the unmapped properties (by finding a similar question from 2 years ago: Handling calculated properties with breezejs and web api)
What I have so far:
function iUIConfigConstructorTool() {
this.ConfigToCurrentUSetting = null;
};
function iUIConfigConstructorAppl() {
this.ConfigToCurrentUSetting = null;
};
function iUIConfigConstructorWidget() {
this.ConfigToCurrentUSetting = null;
};
function iUIConfigInitializer(uiConfigObject) {
// initializing other properties
};
this.manager.metadataStore.registerEntityTypeCtor("Tool", iUIConfigConstructorTool, iUIConfigInitializer);
this.manager.metadataStore.registerEntityTypeCtor("Appl", iUIConfigConstructorAppl, iUIConfigInitializer);
this.manager.metadataStore.registerEntityTypeCtor("Widget", iUIConfigConstructorWidget, iUIConfigInitializer);
This does what I want. Is there a way, to do this over the metamodel from the server? Because I define my calculated properties on the server and the metamodel is delivered by the server, I don't want to change the client-side implementation if I add a new Navigation-Property. So I'd need something like a flag in the metamodel to tell breeze, that this property needs to be filled as it comes over the wire without ForeignKeys etc.
Maybe in other words: We are doing "sub queries" on the server side (e.g. find Customers with it's Orders but only up to a certain Date) for each queried object and deliver this to breeze (in a separate property than the real orders-property of the Customer). Our problem is: How do we unpack this sub-query because there is no direct connection in metadata but we need the connection for the logic.
Please update your question with:
how you obtained/created metadata
metadata for the two endpoints (just the nav props, pk prop, and fk props will do)
the exact query expression
Of course a repro in plunker would be most welcome.
update 7 May 2015
If I understand your comment correctly, the navigation property (properties) in question are to be maintained by you (w/ server-supplied info), not by Breeze.
That leads me to suggest that you maintain them as unmapped properties rather than mapped, navigation properties. Does that make sense?

Using SQLDependency or SqlCacheDependency with Repository pattern

I am building an ASP.NET MVC application using the Repository pattern. A typical method in my Repository is as follows
public IList<T> Select<T>(string cacheKey, string Sql, object filter) where T: new()
{
IList<T> items = MemoryCache.Default.Get(cacheKey) as IList<T>;
if (items == null || !items.Any())
{
items = Connection.Select<T>(Sql, filter);
MemoryCache.Default.Add(cacheKey, items, DateTime.Now.AddMinutes(120));
}
return items;
}
and it is being used as follows
IEnumerable<OSADCOL> osadcols = Repository.Select<OSADCOL>("OSADCOLS__TblId=" + Id, "TBLid = #id", new { id = Id });
In the above mentioned example OSADCOL is a model in my app and represents a Table with the same name in my Database. The Connection.Select function is ORMlite function. I don't use Entity Framework for performance issues. My problem is the following. I am currently cashing the result set for future relevance but I am doing it in a hard coded way. I am caching the result set for 2 hours. It is obvious that a proper implementation would be to discard my cashed data when the OSADCOL's table data changes. It seems that I have to use SQLDependency or SQLCacheDependency. The questions are the following:
How am I going to use SQLDependency or SQLCacheDependency with this Repository?
What is the actual difference between these 2?
It is mentioned in some forums that SQLDependency creates memory leaks? Is that true? And If yes is there an alternative approach?
Any Ideas?

Handling calculated properties with breezejs and web api

I'm experimenting with BreezeJS with Web API using the BreezeControllerAttribute. How should calculated properties on an entity be exposed? The only way I've found to do this reliably is to create an intermediate DTO that inherits from the entity or use a projection. Normally I would use a readonly property for this scenario, but those appear to be ignored.
When Breeze maps JSON property data to entities, it ignores properties that it does not recognize. That's why your server class's calculated property data are discarded even though you see them in the JSON on the wire.
Fortunately, you can teach Breeze to recognize the property by registering it as an unmapped property. I'll show you how. Let me give some background first.
Background
Your calculated property would be "known" to the Breeze client had it been a property calculated by the database. Database-backed properties (regular and calculated) are picked up in metadata as mapped properties.
But in your case (if I understand correctly) the property is defined in the logic of the server-side class, not in the database. Therefore it is not among the mapped properties in metadata. It is hidden from metadata. It is an unmapped instance property.
I assume you're not hiding it from the serializer. If you look at the network traffic for a query of the class, you can see your calculated property data arriving at the client. The problem is that Breeze is ignoring it when it "materializes" entities from these query results.
Solution with example
The solution is to register the calculated property in the MetadataStore.
I modified the entityExtensionTests.js of the DocCode sample to include this scenario; you can get that code from GitHub or wait for the next Breeze release.
Or just follow along with the code below, starting with this snippet from the Employee class in NorthwindModel.cs:
// Unmapped, server-side calculated property
[NotMapped] // Hidden from Entity Framework; still serialized to the client
public string FullName {
get { return LastName +
(String.IsNullOrWhiteSpace(FirstName)? "" : (", " + FirstName)); }
}
And here is the automated test in entityExtensionTests.js
test("unmapped property can be set by a calculated property of the server class", 2,
function () {
var store = cloneModuleMetadataStore(); // clones the Northwind MetadataStore
// custom Employee constructor
var employeeCtor = function () {
//'Fullname' is a server-side calculated property of the Employee class
// This unmapped property will be empty for new entities
// but will be set for existing entities during query materialization
this.FullName = "";
};
// register the custom constructor
store.registerEntityTypeCtor("Employee", employeeCtor);
var fullProp = store.getEntityType('Employee').getProperty('FullName');
ok(fullProp && fullProp.isUnmapped,
"'FullName' should be an unmapped property after registration");
var em = newEm(store); // helper creates a manager using this MetadataStore
var query = EntityQuery.from('Employees').using(em);
stop(); // going async
query.execute().then(success).fail(handleFail).fin(start);
function success(data) {
var first = data.results[0];
var full = first.FullName();
// passing test confirms that the FulllName property has a value
ok(full, "queried 'Employee' should have a fullname ('Last, First'); it is "+full);
}
});
What you need to do is in this small part of the test example:
var yourTypeCtor = function () {
this.calculatedProperty = ""; // "" or instance of whatever type is is supposed to be
};
// register your custom constructor
store.registerEntityTypeCtor("YourType", yourTypeCtor);

Entity Framework CTP5 - Reading Multiple Record Sets From a Stored Procedure

In EF4, this was not easily possible. You either had to degrade to classic ADO.NET (DataReader), use ObjectContext.Translate or use the EFExtensions project.
Has this been implemented off the shelf in EF CTP5?
If not, what is the recommended way of doing this?
Do we have to cast the DbContext<T> as an IObjectContextAdapter and access the underlying ObjectContext in order to get to this method?
Can someone point me to a good article on doing this with EF CTP5?
So i got this working, here's what i have:
internal SomeInternalPOCOWrapper FindXXX(string xxx)
{
Condition.Requires(xxx).IsNotNullOrEmpty();
var someInternalPokey = new SomeInternalPOCOWrapper();
var ctx = (this as IObjectContextAdapter).ObjectContext;
var con = new SqlConnection("xxxxx");
{
con.Open();
DbCommand cmd = con.CreateCommand();
cmd.CommandText = "exec dbo.usp_XXX #xxxx";
cmd.Parameters.Add(new SqlParameter("xxxx", xxx));
using (var rdr = cmd.ExecuteReader())
{
// -- RESULT SET #1
someInternalPokey.Prop1 = ctx.Translate<InternalPoco1>(rdr);
// -- RESULT SET #2
rdr.NextResult();
someInternalPokey.Prop2 = ctx.Translate<InternalPoco2>(rdr);
// -- RESULT SET #3
rdr.NextResult();
someInternalPokey.Prop3 = ctx.Translate<InternalPoco3>(rdr);
// RESULT SET #4
rdr.NextResult();
someInternalPokey.Prop4 = ctx.Translate<InternalPoco4>(rdr);
}
con.Close();
}
return someInternalPokey;
}
Essentially, it's basically like classic ADO.NET. You read the DbReader, advance to the next result set, etc.
But at least we have the Translate method which seemingly does a left-to-right between the result set fields and the supplied entity.
Note the method is internal.
My Repository calls this method, then hydrates the DTO into my domain objects.
I'm not 100% happy with it for 3 reasons:
We have to cast the DbContext as IObjectContextAdapter. The method Translate should be on DbContext<T> class IMO.
We have to use classic ADO.NET Objects. Why? Stored Procedures are a must have for any ORM. My main gripe with EF is the lack of the stored procedure support and this seems to not have been rectified with EF CTP5.
You have to open a new SqlConnection. Why can't it use the same connection as the one opened by the EF Context?
Hope this both helps someone and sends out a message to the EF team. We need multiple result support for SPROCS off the shelf. You can map a stored proc to a complex type, so why can't we map a stored proc to multiple complex types?

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