Exception - System.InvalidOperationException: Client projection contains reference to constant expression of type: Microsoft.AspNetCore.DataProtection.EntityFrameworkCore.EntityFrameworkCoreXmlRepository<DataProtectionKeysDbContext>. This could potentially cause memory leak.

[smuthiya]

With .NET Core 3.0 Preview 9 - in ASP.NET Core Web API Project - when data protection is used following exception occurs

System.InvalidOperationException: Client projection contains reference to constant expression of type: Microsoft.AspNetCore.DataProtection.EntityFrameworkCore.EntityFrameworkCoreXmlRepository<Varian.Eventing.Dal.DbContexts.DataProtectionKeysContext>. This could potentially cause memory leak.

Following is the complete stacktrace -

System.InvalidOperationException: Client projection contains reference to constant expression of type: Microsoft.AspNetCore.DataProtection.EntityFrameworkCore.EntityFrameworkCoreXmlRepository<Varian.Eventing.Dal.DbContexts.DataProtectionKeysContext>. This could potentially cause memory leak.
at Microsoft.EntityFrameworkCore.Query.ShapedQueryCompilingExpressionVisitor.ConstantVerifyingExpressionVisitor.VisitConstant(ConstantExpression constantExpression)
at System.Linq.Expressions.ConstantExpression.Accept(ExpressionVisitor visitor)
at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
at System.Linq.Expressions.ExpressionVisitor.VisitMethodCall(MethodCallExpression node)
at System.Linq.Expressions.MethodCallExpression.Accept(ExpressionVisitor visitor)
at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
at System.Dynamic.Utils.ExpressionVisitorUtils.VisitBlockExpressions(ExpressionVisitor visitor, BlockExpression block)
at System.Linq.Expressions.ExpressionVisitor.VisitBlock(BlockExpression node)
at System.Linq.Expressions.BlockExpression.Accept(ExpressionVisitor visitor)
at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
at System.Linq.Expressions.ExpressionVisitor.VisitLambda[T](Expression1 node) at System.Linq.Expressions.Expression1.Accept(ExpressionVisitor visitor)
at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
at Microsoft.EntityFrameworkCore.Query.ShapedQueryCompilingExpressionVisitor.InjectEntityMaterializers(Expression expression)
at Microsoft.EntityFrameworkCore.Query.RelationalShapedQueryCompilingExpressionVisitor.VisitShapedQueryExpression(ShapedQueryExpression shapedQueryExpression)
at Microsoft.EntityFrameworkCore.Query.ShapedQueryCompilingExpressionVisitor.VisitExtension(Expression extensionExpression)
at System.Linq.Expressions.Expression.Accept(ExpressionVisitor visitor)
at System.Linq.Expressions.ExpressionVisitor.Visit(Expression node)
at Microsoft.EntityFrameworkCore.Query.QueryCompilationContext.CreateQueryExecutor[TResult](Expression query)
at Microsoft.EntityFrameworkCore.Storage.Database.CompileQuery[TResult](Expression query, Boolean async)
at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.CompileQueryCore[TResult](IDatabase database, Expression query, IModel model, Boolean async)
at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.<>c__DisplayClass9_01.<Execute>b__0() at Microsoft.EntityFrameworkCore.Query.Internal.CompiledQueryCache.GetOrAddQueryCore[TFunc](Object cacheKey, Func1 compiler)
at Microsoft.EntityFrameworkCore.Query.Internal.CompiledQueryCache.GetOrAddQuery[TResult](Object cacheKey, Func1 compiler) at Microsoft.EntityFrameworkCore.Query.Internal.QueryCompiler.Execute[TResult](Expression query) at Microsoft.EntityFrameworkCore.Query.Internal.EntityQueryProvider.Execute[TResult](Expression expression) at Microsoft.EntityFrameworkCore.Query.Internal.EntityQueryable1.GetEnumerator()
at System.Collections.Generic.List1..ctor(IEnumerable1 collection)
at System.Linq.Enumerable.ToList[TSource](IEnumerable1 source) at Microsoft.AspNetCore.DataProtection.EntityFrameworkCore.EntityFrameworkCoreXmlRepository1.GetAllElements()
at Microsoft.AspNetCore.DataProtection.KeyManagement.XmlKeyManager.GetAllKeys()
at Microsoft.AspNetCore.DataProtection.KeyManagement.KeyRingProvider.CreateCacheableKeyRingCore(DateTimeOffset now, IKey keyJustAdded)
at Microsoft.AspNetCore.DataProtection.KeyManagement.KeyRingProvider.Microsoft.AspNetCore.DataProtection.KeyManagement.Internal.ICacheableKeyRingProvider.GetCacheableKeyRing(DateTimeOffset now)
at Microsoft.AspNetCore.DataProtection.KeyManagement.KeyRingProvider.GetCurrentKeyRingCore(DateTime utcNow, Boolean forceRefresh)

Expected behavior

The above exception should not occur

[blowdart]

Dupe of #13696

Fixed in #13743