[nhusers] Message "Session has already been garbage collected"

[David_L]

I upgraded my Project to NH5 last week. Now I have a question about a
Message I have never seen before: "Session has already been garbage
collected"

My code was Querying through lazy linked (many-to-one/one-to-many) Entities
via LINQ. Everything worked without Exception in the past (with NH4). A
customer reported me this message. I personally have never seen it...

StackTrace of my customer report:

Message:An error has occurred.,ExceptionMessage:Session has already been
garbage
collected,ExceptionType:System.InvalidOperationException,StackTrace:
bei NHibernate.Linq.DefaultQueryProvider.get_Session()
bei NHibernate.Linq.DefaultQueryProvider.PrepareQuery(Expression
expression, IQuery query)
bei NHibernate.Linq.DefaultQueryProvider.Execute(Expression expression)
bei NHibernate.Linq.DefaultQueryProvider.Execute[TResult](Expression
expression)
bei Remotion.Linq.QueryableBase`1.GetEnumerator()
bei System.Linq.Enumerable.<SelectManyIterator>d__16`2.MoveNext()
bei System.Linq.Enumerable.<DistinctIterator>d__63`1.MoveNext()
bei System.Linq.Buffer`1..ctor(IEnumerable`1 source)
bei System.Linq.Enumerable.ToArray[TSource](IEnumerable`1 source)
bei
MediaServices.Services.Implementation.ServiceBaseWebApi.FillModelExtras(Asset[]
assets)
bei MediaServices.Services.Implementation.OfferService.OfferGalery(Int64
offerProgramId)

My code in OfferGalery loads some entiteis from database with a
Session.Query<xxx>().Where... Statement. Then I Fill my Model
(FillModelExtras) navigating through the loaded entities and
lazy-sub-entities.

Under which conditions does this Message come up? And what can I do to
avoid it?

[f***@free.fr]

The NHibernate LINQ provider has a weak reference on the session, allowing
the session to get garbaged collected if nothing else than the query
provider references it.

If a Linq query is used after having let the session it is bound to go
un-referenced, then this message may occur. This is a change in NHibernate
5.0: previously, the weak reference was "resurrecting" the session instead,
but in an unpredictable state.

Post by David_L
I upgraded my Project to NH5 last week. Now I have a question about a
Message I have never seen before: "Session has already been garbage
collected"
My code was Querying through lazy linked (many-to-one/one-to-many)
Entities via LINQ. Everything worked without Exception in the past (with
NH4). A customer reported me this message. I personally have never seen
it...
Message:An error has occurred.,ExceptionMessage:Session has already been
garbage
bei NHibernate.Linq.DefaultQueryProvider.get_Session()
bei NHibernate.Linq.DefaultQueryProvider.PrepareQuery(Expression
expression, IQuery query)
bei NHibernate.Linq.DefaultQueryProvider.Execute(Expression expression)
bei NHibernate.Linq.DefaultQueryProvider.Execute[TResult](Expression
expression)
bei Remotion.Linq.QueryableBase`1.GetEnumerator()
bei System.Linq.Enumerable.<SelectManyIterator>d__16`2.MoveNext()
bei System.Linq.Enumerable.<DistinctIterator>d__63`1.MoveNext()
bei System.Linq.Buffer`1..ctor(IEnumerable`1 source)
bei System.Linq.Enumerable.ToArray[TSource](IEnumerable`1 source)
bei
MediaServices.Services.Implementation.ServiceBaseWebApi.FillModelExtras(Asset[]
assets)
bei MediaServices.Services.Implementation.OfferService.OfferGalery(Int64
offerProgramId)
My code in OfferGalery loads some entiteis from database with a
Session.Query<xxx>().Where... Statement. Then I Fill my Model
(FillModelExtras) navigating through the loaded entities and
lazy-sub-entities.
Under which conditions does this Message come up? And what can I do to
avoid it?