public virtual void Add <T>(T instance) where T : class
{
if (instance == null)
{
throw new ArgumentNullException(nameof(instance));
}
var type = typeof(T);
var value = _idAccessor.GetId(instance);
var key = _idManager.GetFromId(typeof(T), value);
if (key == null)
{
key = _idManager.GenerateId(type);
_idAccessor.SetId(instance, key.Id);
}
var entry = new SessionEntry()
{
Action = ActionType.Add,
Instance = instance,
Key = key
};
_sessionCache.Attach(entry);
}
protected virtual async Task <IEnumerable <T> > Load <T>(IEnumerable ids, ISessionCache sessionCache,
ITrackingProvider tracking, IAction <IEnumerable <LoadContext> > loadTask) where T : class
{
//setup the pipeline
var pipe = new Middleware <IEnumerable <LoadContext> >();
pipe.Use(new TrackingAction <LoadContext>(tracking));
pipe.Use(new SessionAction <LoadContext>(sessionCache));
pipe.Use(loadTask);
//setup the load context
var type = typeof(T);
var loadContexts = ids.Cast <object>().Select(id =>
{
var idKey = _idManager.GetFromId(type, id);
return(new LoadContext()
{
Key = idKey,
Type = type
});
}).ToList();
await pipe.Execute(loadContexts);
return(loadContexts.Select(x => x.Entity).Where(x => x != null).Cast <T>());
}
public Task <IEnumerable <LoadContext> > Execute(QueryContext context,
Next <QueryContext, IEnumerable <LoadContext> > next)
{
var ctx = context;
var q = ctx.Query;
var query = new MongoQueryRequest
{
Selector = q.Selector,
Limit = q.Limit,
Skip = q.Skip,
Sort = q.Sort
};
var allDocs = _couchDb.MongoQuery(query);
//using the loaded docs, update the context entries.
var results =
(from entity in allDocs.Docs
let id = _idAccessor.GetId(entity)
let key = _idManager.GetFromId(entity.GetType(), id)
select new LoadContext()
{
Entity = entity,
Key = key,
Type = entity.GetType()
}).ToList();
return(Task.FromResult((IEnumerable <LoadContext>)results));
}
public Task Execute(IEnumerable <LoadContext> context, Next <IEnumerable <LoadContext> > next)
{
var items = context.ToList(); //ensure 1 iteration over list. (tasks to run once)
//we do not want to load items which have been loaded from the cache
var toLoad = items.Where(x => !x.LoadedFromCache).ToDictionary(loadContext => loadContext.Key.CouchDbId);
var allDocs = _couchDb.LoadAllEntities(new AllDocsRequest()
{
Keys = toLoad.Keys
});
//using the loaded docs, update the context entries.
foreach (var entity in allDocs.Rows.Select(x => x.Doc))
{
var id = _idAccessor.GetId(entity);
var key = _idManager.GetFromId(entity.GetType(), id);
toLoad[key.CouchDbId].Entity = entity;
}
return(Task.CompletedTask);
}
