/// <summary>
/// Composes and executes the query asynchronously based on the <see cref="RemoteLinq.Expression"/> and maps the result into dynamic objects.
/// </summary>
/// <remarks>
/// Multiple active operations on the same EF context instance are not supported. Use 'await' to ensure
/// that any asynchronous operations have completed before calling another method on the same context.
/// </remarks>
/// <param name="expression">The <see cref="RemoteLinq.Expression"/> to be executed.</param>
/// <param name="cancellation">A <see cref="CancellationToken" /> to observe while waiting for the task to complete.</param>
/// <returns>
/// A task that represents the asynchronous operation.
/// The task result contains the mapped result of the query execution.
/// </returns>
public async ValueTask <TDataTranferObject> ExecuteAsync(RemoteLinq.Expression expression, CancellationToken cancellation = default)
{
expression.AssertNotNull(nameof(expression));
var ctx = Context;
var preparedRemoteExpression = Prepare(expression);
ctx.RemoteExpression = preparedRemoteExpression;
var linqExpression = Transform(preparedRemoteExpression);
var preparedLinqExpression = PrepareAsyncQuery(linqExpression, cancellation);
ctx.SystemExpression = preparedLinqExpression;
var queryResult = await ExecuteAsync(preparedLinqExpression, cancellation).ConfigureAwait(false);
var processedResult = ProcessResult(queryResult);
var dynamicObjects = ConvertResult(processedResult);
var processedDynamicObjects = ProcessResult(dynamicObjects);
return(processedDynamicObjects);
}
private static IQueryable <T1> BuildQuery <T1, T2>(IQueryable <T1> queriable1, IQueryable <T2> queriable2)
where T1 : IValue
where T2 : IValue
{
Expression <Func <T2, bool> > subfilter =
x => x.Value % 2 == 0;
Expression <Func <T1, bool> > outerfilter =
x => queriable2.Where(subfilter).Where(d => d.Value == x.Value).Any();
return(queriable1.Where(outerfilter));
}
/// <summary>
/// Composes and executes the query based on the <see cref="RemoteLinq.Expression"/>.
/// </summary>
/// <param name="expression">The <see cref="RemoteLinq.Expression"/> to be executed.</param>
/// <param name="cancellation">A <see cref="CancellationToken" /> to observe while waiting for the async operation to complete.</param>
/// <returns>The mapped result of the query execution.</returns>
public IAsyncEnumerable <TDataTranferObject> ExecuteAsyncStream(RemoteLinq.Expression expression, CancellationToken cancellation = default)
{
var ctx = Context;
var preparedRemoteExpression = Prepare(expression);
ctx.RemoteExpression = preparedRemoteExpression;
var linqExpression = Transform(preparedRemoteExpression);
var preparedLinqExpression = Prepare(linqExpression);
ctx.SystemExpression = preparedLinqExpression;
var queryResult = ExecuteAsyncStream(preparedLinqExpression, cancellation);
var processedResult = ProcessResult(queryResult);
var dataTransferObjects = ConvertResult(processedResult);
var processedDataTransferObjects = ProcessResult(dataTransferObjects);
return(processedDataTransferObjects);
}
/// <summary>
/// Composes and executes the query based on the <see cref="RemoteLinq.Expression"/> and maps the result into dynamic objects.
/// </summary>
/// <param name="expression">The <see cref="RemoteLinq.Expression"/> to be executed.</param>
/// <returns>The mapped result of the query execution.</returns>
public TDataTranferObject Execute(RemoteLinq.Expression expression)
{
var ctx = Context;
var preparedRemoteExpression = Prepare(expression);
ctx.RemoteExpression = preparedRemoteExpression;
var linqExpression = Transform(preparedRemoteExpression);
var preparedLinqExpression = Prepare(linqExpression);
ctx.SystemExpression = preparedLinqExpression;
var queryResult = Execute(preparedLinqExpression);
var processedResult = ProcessResult(queryResult);
var dataTransferObjects = ConvertResult(processedResult);
var processedDataTransferObjects = ProcessResult(dataTransferObjects);
return(processedDataTransferObjects);
}
public SystemLinq.Expression ToExpression(RemoteLinq.Expression expression) => Visit(expression.CheckNotNull(nameof(expression)));
/// <summary> /// Transforms the <see cref="RemoteLinq.Expression"/> to a <see cref="SystemLinq.Expression"/>. /// </summary> /// <param name="expression">The <see cref="RemoteLinq.Expression"/> to be transformed.</param> /// <returns>A <see cref="SystemLinq.Expression"/>.</returns> protected virtual SystemLinq.Expression Transform(RemoteLinq.Expression expression) => expression.ToLinqExpression(_context);
/// <summary> /// Prepares the <see cref="RemoteLinq.Expression"/> befor being transformed.<para/> /// </summary> /// <param name="expression">The <see cref="RemoteLinq.Expression"/>.</param> /// <returns>A <see cref="SystemLinq.Expression"/>.</returns> protected virtual RemoteLinq.Expression Prepare(RemoteLinq.Expression expression) => expression .ReplaceNonGenericQueryArgumentsByGenericArguments() .ReplaceResourceDescriptorsByQueryable(_queryableProvider, _context.TypeResolver);
SystemLinq.Expression IAsyncStreamExpressionExecutionDecorator <TDataTranferObject> .Transform(RemoteLinq.Expression expression) => Transform(expression);
RemoteLinq.Expression IAsyncStreamExpressionExecutionDecorator <TDataTranferObject> .Prepare(RemoteLinq.Expression expression) => Prepare(expression);
protected override RemoteLinq.Expression Prepare(RemoteLinq.Expression expression) => _transform(base.Prepare(expression));
protected override RemoteLinq.Expression Prepare(RemoteLinq.Expression expression) => base.Prepare(expression) .MapIncludeQueryMethods();
public static SystemLinq.Expression ToLinqExpression(this RemoteLinq.Expression expression, ITypeResolver?typeResolver) => ToLinqExpression(expression, GetExpressionTranslatorContextOrNull(typeResolver));
/// <summary> /// Translates a given remote linq expression into an system linq expression. /// </summary> public static SystemLinq.Expression ToLinqExpression(this RemoteLinq.Expression expression, IExpressionFromRemoteLinqContext?context = null) => new RemoteToSystemLinqTranslator(context ?? ExpressionTranslatorContext.Default).ToExpression(expression);
public ResultWrapperExpression(RemoteLinq.Expression result, Type type)
{
Result = result;
Type = type;
}