/// <summary>Gets database expression.</summary>
/// <param name="context">The context.</param>
/// <param name="type">The type.</param>
/// <returns>The database expression.</returns>
public override DbExpression GetDbExpression(DbContext context, Type type)
{
var contextFullName = context.GetType().AssemblyQualifiedName ?? context.GetType().FullName;
var typeFullName = type.AssemblyQualifiedName ?? type.FullName;
var hookId = QueryFilterManager.PrefixHook + contextFullName + ";" + typeFullName + ";" + UniqueKey;
if (!QueryFilterManager.DbExpressionByHook.ContainsKey(hookId))
{
// CREATE set
var setMethod = typeof(DbContext).GetMethod("Set", new Type[0]).MakeGenericMethod(type);
var dbSet = (IQueryable <T>)setMethod.Invoke(context, null);
// APPLY filter
dbSet = Filter(dbSet);
// APPLY hook
dbSet = QueryFilterManager.HookFilter(dbSet, hookId);
// HOOK the filter
var objectQuery = dbSet.GetObjectQuery();
var commandTextAndParameters = objectQuery.GetCommandTextAndParameters();
// ADD parameter
QueryFilterManager.DbExpressionParameterByHook.AddOrUpdate(QueryFilterManager.DbExpressionByHook[hookId], commandTextAndParameters.Item2, (s, list) => list);
}
// TODO: WeakTable ?
return(QueryFilterManager.DbExpressionByHook[hookId]);
}
/// <summary>Gets database expression.</summary>
/// <param name="context">The context.</param>
/// <param name="type">The type.</param>
/// <returns>The database expression.</returns>
public override DbExpression GetDbExpression(DbContext context, Type type)
{
var contextFullName = context.GetType().AssemblyQualifiedName ?? context.GetType().FullName;
var typeFullName = type.AssemblyQualifiedName ?? type.FullName;
var hookId = QueryFilterManager.PrefixHook + contextFullName + ";" + typeFullName + ";" + UniqueKey;
if (!QueryFilterManager.DbExpressionByHook.ContainsKey(hookId))
{
// CREATE set
var setMethod = typeof(DbContext).GetMethod("Set", new Type[0]).MakeGenericMethod(type);
var dbSet = (IQueryable <T>)setMethod.Invoke(context, null);
// APPLY filter
dbSet = Filter(dbSet);
// APPLY hook
dbSet = QueryFilterManager.HookFilter(dbSet, hookId);
// Hook the filter
var objectQuery = dbSet.GetObjectQuery();
objectQuery.ToTraceString();
}
// TODO: WeakTable ?
return(QueryFilterManager.DbExpressionByHook[hookId]);
}
/// <summary>
/// Filter the query using context filters associated with specified keys.
/// </summary>
/// <typeparam name="T">The type of elements of the query.</typeparam>
/// <param name="query">The query to filter using context filters associated with specified keys.</param>
/// <param name="keys">
/// A variable-length parameters list containing keys associated to context filters to use to filter the
/// query.
/// </param>
/// <returns>The query filtered using context filters associated with specified keys.</returns>
public static IQueryable <T> Filter <T>(this IDbSet <T> query, params object[] keys) where T : class
{
var filterContext = QueryFilterManager.AddOrGetFilterContext(query.GetDbContext());
var filterHook = QueryFilterManager.EnableFilterById;
var sb = new StringBuilder();
if (keys != null)
{
foreach (var key in keys)
{
var filter = filterContext.GetFilter(key);
if (filter == null)
{
continue;
}
sb.Append(filter.UniqueKey);
sb.Append(";");
}
}
return(QueryFilterManager.HookFilter(query.AsNoFilter(), filterHook + sb));
}
/// <summary>Return the orginal query before the context was filtered.</summary>
/// <typeparam name="T">The type of elements of the query.</typeparam>
/// <param name="query">The filtered query from which the original query should be retrieved.</param>
/// <returns>The orginal query before the context was filtered.</returns>
public static IQueryable <T> AsNoFilter <T>(this IDbSet <T> query) where T : class
{
return(QueryFilterManager.HookFilter(query, QueryFilterManager.DisableAllFilter));
}