RavenDB how to flush? | 易学教程

问题

I am using RavenDb embedded. As a part of my intergration tests I want to check objects are persisted. When I SaveChanges on an object, then retrieve it, it cannot be found unless I dispose my connection.

This does not work for me, as no files are returned

 using (var session = _dataDocumentStore.Instance.OpenSession())
 {
         session.Store(file);
         session.SaveChanges();
 }

....

using (var session = _dataDocumentStore.Instance.OpenSession() )
{
          return session.Query<File>().ToList();
}

I created a Flush method which disposes and recreates a EmbeddableDocumentStore which works, but as this is somthing that feels fundamental I may be going about things the wrong way:

  public static IDocumentStore Initialize()
        {
            instance = new EmbeddableDocumentStore
            {
                DataDirectory = "App_Data/Database",
                UseEmbeddedHttpServer = true,


            };

            instance.Initialize();
            return instance;
        }

        public void Flush()
        {
            instance.Dispose();
            Initialize();

        }

How do you persist in RavenDB and then check it has been persisted? Any advice on this would be great

回答1:

Basically, the EmbeddableDocumentStore takes longer to save and Index that new data, than saving and querying.

So when your tests say:-

Store and SaveChanges.
Load.
Did this load?

the load completes waaay quicker than the indexing has had time to finish.

So, Like Daniel Lang said, u need to wait for stale results.

BUT .. you'll have to do that for -every- query you wish to check, in your code. So .. lets cheat (legally) :)

Tell your document store to ALWAYS wait for stale results, if something queries the store.

How?

// Initialise the Store.
var documentStore = new EmbeddableDocumentStore
                    {
                        RunInMemory = true
                    };
documentStore.Initialize();

// Force query's to wait for index's to catch up. Unit Testing only :P
documentStore.RegisterListener(new NoStaleQueriesListener());

....


#region Nested type: NoStaleQueriesListener

public class NoStaleQueriesListener : IDocumentQueryListener
{
    #region Implementation of IDocumentQueryListener

    public void BeforeQueryExecuted(IDocumentQueryCustomization queryCustomization)
    {
        queryCustomization.WaitForNonStaleResults();
    }

    #endregion
}

#endregion

Now to see this in action, check out RavenOverflow @ github. And the Tests project in that solution has all the love you might want :)

回答2:

The reason is, that ravens index is too stale to return something here. You need to do this:

session.Query<File>()
    .Customize(x => x.WaitForNonStaleResultsAsOfLastWrite())
    .ToList();

For further reading, go here: http://ravendb.net/docs/client-api/querying/stale-indexes

来源：https://stackoverflow.com/questions/9181204/ravendb-how-to-flush

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persistence

ravendb

flush