modules/platforms/dotnet/Apache.Ignite.Linq/Impl/CacheFieldsQueryExecutor.cs - ignite - Git at Google

 /*
  * Licensed to the Apache Software Foundation (ASF) under one or more
  * contributor license agreements.  See the NOTICE file distributed with
  * this work for additional information regarding copyright ownership.
  * The ASF licenses this file to You under the Apache License, Version 2.0
  * (the "License"); you may not use this file except in compliance with
  * the License.  You may obtain a copy of the License at
  *
  *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  * See the License for the specific language governing permissions and
  * limitations under the License.
  */

 namespace Apache.Ignite.Linq.Impl
 {
     using System;
     using System.Collections.Generic;
     using System.Diagnostics;
     using System.Diagnostics.CodeAnalysis;
     using System.Linq;
     using System.Linq.Expressions;
     using System.Reflection;
     using Apache.Ignite.Core.Binary;
     using Apache.Ignite.Core.Cache;
     using Apache.Ignite.Core.Cache.Query;
     using Apache.Ignite.Core.Impl.Cache;
     using Apache.Ignite.Core.Impl.Common;
     using Remotion.Linq;

     /// <summary>
     /// Fields query executor.
     /// </summary>
     internal class CacheFieldsQueryExecutor : IQueryExecutor
     {
         /** */
         private readonly ICacheInternal _cache;

         /** */
         private readonly QueryOptions _options;

         /** */
         private static readonly CopyOnWriteConcurrentDictionary<ConstructorInfo, object> CtorCache =
             new CopyOnWriteConcurrentDictionary<ConstructorInfo, object>();

         /// <summary>
         /// Initializes a new instance of the <see cref="CacheFieldsQueryExecutor" /> class.
         /// </summary>
         /// <param name="cache">The executor function.</param>
         /// <param name="options">Query options.</param>
         public CacheFieldsQueryExecutor(ICacheInternal cache, QueryOptions options)
         {
             Debug.Assert(cache != null);
             Debug.Assert(options != null);

             _cache = cache;
             _options = options;
         }

         /** <inheritdoc /> */
         public T ExecuteScalar<T>(QueryModel queryModel)
         {
             return ExecuteSingle<T>(queryModel, false);
         }

         /** <inheritdoc /> */
         public T ExecuteSingle<T>(QueryModel queryModel, bool returnDefaultWhenEmpty)
         {
             var col = ExecuteCollection<T>(queryModel);

             return returnDefaultWhenEmpty ? col.SingleOrDefault() : col.Single();
         }

         /** <inheritdoc /> */
         [SuppressMessage("Microsoft.Design", "CA1062:Validate arguments of public methods")]
         public IEnumerable<T> ExecuteCollection<T>(QueryModel queryModel)
         {
             Debug.Assert(queryModel != null);

             var qryData = GetQueryData(queryModel);

             Debug.WriteLine("\nFields Query: {0} | {1}", qryData.QueryText,
                 string.Join(", ", qryData.Parameters.Select(x => x == null ? "null" : x.ToString())));

             var qry = GetFieldsQuery(qryData.QueryText, qryData.Parameters.ToArray());

             var selector = GetResultSelector<T>(queryModel.SelectClause.Selector);

             return _cache.Query(qry, selector);
         }

         /// <summary>
         /// Compiles the query without regard to number or order of arguments.
         /// </summary>
         public Func<object[], IQueryCursor<T>> CompileQuery<T>(QueryModel queryModel)
         {
             Debug.Assert(queryModel != null);

             var qryText = GetQueryData(queryModel).QueryText;
             var selector = GetResultSelector<T>(queryModel.SelectClause.Selector);

             return args => _cache.Query(GetFieldsQuery(qryText, args), selector);
         }

         /// <summary>
         /// Compiles the query.
         /// </summary>
         /// <typeparam name="T">Result type.</typeparam>
         /// <param name="queryModel">The query model.</param>
         /// <param name="queryLambdaModel">The query model generated from lambda body.</param>
         /// <param name="queryLambda">The query lambda.</param>
         /// <returns>Compiled query func.</returns>
         public Func<object[], IQueryCursor<T>> CompileQuery<T>(QueryModel queryModel, QueryModel queryLambdaModel,
             LambdaExpression queryLambda)
         {
             Debug.Assert(queryModel != null);

             // Get model from lambda to map arguments properly.
             var qryData = GetQueryData(queryLambdaModel);

             var qryText = GetQueryData(queryModel).QueryText;
             var qryTextLambda = qryData.QueryText;

             if (qryText != qryTextLambda)
             {
                 Debug.WriteLine(qryText);
                 Debug.WriteLine(qryTextLambda);

                 throw new InvalidOperationException("Error compiling query: entire LINQ expression should be " +
                                                     "specified within lambda passed to Compile method. " +
                                                     "Part of the query can't be outside the Compile method call.");
             }

             var selector = GetResultSelector<T>(queryModel.SelectClause.Selector);

             var qryParams = qryData.Parameters.ToArray();

             // Compiled query is a delegate with query parameters
             // Delegate parameters order and query parameters order may differ

             // Simple case: lambda with no parameters. Only embedded parameters are used.
             if (!queryLambda.Parameters.Any())
             {
                 return argsUnused => _cache.Query(GetFieldsQuery(qryText, qryParams), selector);
             }

             // These are in order of usage in query
             var qryOrderArgs = qryParams.OfType<ParameterExpression>().Select(x => x.Name).ToArray();

             // These are in order they come from user
             var userOrderArgs = queryLambda.Parameters.Select(x => x.Name).ToList();

             // Simple case: all query args directly map to the lambda args in the same order
             if (qryOrderArgs.Length == qryParams.Length
                 && qryOrderArgs.SequenceEqual(userOrderArgs))
             {
                 return args => _cache.Query(GetFieldsQuery(qryText, args), selector);
             }

             // General case: embedded args and lambda args are mixed; same args can be used multiple times.
             // Produce a mapping that defines where query arguments come from.
             var mapping = qryParams.Select(x =>
             {
                 var pe = x as ParameterExpression;

                 if (pe != null)
                     return userOrderArgs.IndexOf(pe.Name);

                 return -1;
             }).ToArray();

             return args => _cache.Query(
                 GetFieldsQuery(qryText, MapQueryArgs(args, qryParams, mapping)), selector);
         }

         /// <summary>
         /// Maps the query arguments.
         /// </summary>
         private static object[] MapQueryArgs(object[] userArgs, object[] embeddedArgs, int[] mapping)
         {
             var mappedArgs = new object[embeddedArgs.Length];

             for (var i = 0; i < mappedArgs.Length; i++)
             {
                 var map = mapping[i];

                 mappedArgs[i] = map < 0 ? embeddedArgs[i] : userArgs[map];
             }

             return mappedArgs;
         }

         /// <summary>
         /// Gets the fields query.
         /// </summary>
         internal SqlFieldsQuery GetFieldsQuery(string text, object[] args)
         {
             return new SqlFieldsQuery(text)
             {
                 EnableDistributedJoins = _options.EnableDistributedJoins,
                 PageSize = _options.PageSize,
                 EnforceJoinOrder = _options.EnforceJoinOrder,
                 Timeout = _options.Timeout,
 #pragma warning disable 618
                 ReplicatedOnly = _options.ReplicatedOnly,
 #pragma warning restore 618
                 Colocated = _options.Colocated,
                 Local = _options.Local,
                 Arguments = args,
                 Lazy = _options.Lazy,
                 UpdateBatchSize = _options.UpdateBatchSize,
                 Partitions = _options.Partitions
             };
         }

         /// <summary>
         /// Generates <see cref="QueryData"/> from specified <see cref="QueryModel"/>.
         /// </summary>
         public static QueryData GetQueryData(QueryModel queryModel)
         {
             Debug.Assert(queryModel != null);

             return new CacheQueryModelVisitor().GenerateQuery(queryModel);
         }

         /// <summary>
         /// Gets the result selector.
         /// </summary>
         private static Func<IBinaryRawReader, int, T> GetResultSelector<T>(Expression selectorExpression)
         {
             var newExpr = selectorExpression as NewExpression;

             if (newExpr != null)
                 return GetCompiledCtor<T>(newExpr.Constructor);

             var entryCtor = GetCacheEntryCtorInfo(typeof(T));

             if (entryCtor != null)
                 return GetCompiledCtor<T>(entryCtor);

             if (typeof(T) == typeof(bool))
                 return ReadBool<T>;

             return (reader, count) => reader.ReadObject<T>();
         }

         /// <summary>
         /// Reads the bool. Actual data may be bool or int/long.
         /// </summary>
         private static T ReadBool<T>(IBinaryRawReader reader, int count)
         {
             var obj = reader.ReadObject<object>();

             if (obj is bool)
                 return (T) obj;

             if (obj is long)
                 return TypeCaster<T>.Cast((long) obj != 0);

             if (obj is int)
                 return TypeCaster<T>.Cast((int) obj != 0);

             throw new InvalidOperationException("Expected bool, got: " + obj);
         }

         /// <summary>
         /// Gets the cache entry constructor.
         /// </summary>
         private static ConstructorInfo GetCacheEntryCtorInfo(Type entryType)
         {
             if (!entryType.IsGenericType || entryType.GetGenericTypeDefinition() != typeof(ICacheEntry<,>))
                 return null;

             var args = entryType.GetGenericArguments();

             var targetType = typeof (CacheEntry<,>).MakeGenericType(args);

             return targetType.GetConstructors().Single();
         }

         /// <summary>
         /// Gets the compiled constructor.
         /// </summary>
         private static Func<IBinaryRawReader, int, T> GetCompiledCtor<T>(ConstructorInfo ctorInfo)
         {
             object result;

             if (CtorCache.TryGetValue(ctorInfo, out result))
                 return (Func<IBinaryRawReader, int, T>) result;

             return (Func<IBinaryRawReader, int, T>) CtorCache.GetOrAdd(ctorInfo, x =>
             {
                 var innerCtor1 = DelegateConverter.CompileCtor<T>(x, GetCacheEntryCtorInfo);

                 return (Func<IBinaryRawReader, int, T>) ((r, c) => innerCtor1(r));
             });
         }
     }
 }
	/*
	* Licensed to the Apache Software Foundation (ASF) under one or more
	* contributor license agreements. See the NOTICE file distributed with
	* this work for additional information regarding copyright ownership.
	* The ASF licenses this file to You under the Apache License, Version 2.0
	* (the "License"); you may not use this file except in compliance with
	* the License. You may obtain a copy of the License at
	*
	* http://www.apache.org/licenses/LICENSE-2.0
	*
	* Unless required by applicable law or agreed to in writing, software
	* distributed under the License is distributed on an "AS IS" BASIS,
	* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
	* See the License for the specific language governing permissions and
	* limitations under the License.
	*/

	namespace Apache.Ignite.Linq.Impl
	{
	using System;
	using System.Collections.Generic;
	using System.Diagnostics;
	using System.Diagnostics.CodeAnalysis;
	using System.Linq;
	using System.Linq.Expressions;
	using System.Reflection;
	using Apache.Ignite.Core.Binary;
	using Apache.Ignite.Core.Cache;
	using Apache.Ignite.Core.Cache.Query;
	using Apache.Ignite.Core.Impl.Cache;
	using Apache.Ignite.Core.Impl.Common;
	using Remotion.Linq;

	/// <summary>
	/// Fields query executor.
	/// </summary>
	internal class CacheFieldsQueryExecutor : IQueryExecutor
	{
	/** */
	private readonly ICacheInternal _cache;

	/** */
	private readonly QueryOptions _options;

	/** */
	private static readonly CopyOnWriteConcurrentDictionary<ConstructorInfo, object> CtorCache =
	new CopyOnWriteConcurrentDictionary<ConstructorInfo, object>();

	/// <summary>
	/// Initializes a new instance of the <see cref="CacheFieldsQueryExecutor" /> class.
	/// </summary>
	/// <param name="cache">The executor function.</param>
	/// <param name="options">Query options.</param>
	public CacheFieldsQueryExecutor(ICacheInternal cache, QueryOptions options)
	{
	Debug.Assert(cache != null);
	Debug.Assert(options != null);

	_cache = cache;
	_options = options;
	}

	/** <inheritdoc /> */
	public T ExecuteScalar<T>(QueryModel queryModel)
	{
	return ExecuteSingle<T>(queryModel, false);
	}

	/** <inheritdoc /> */
	public T ExecuteSingle<T>(QueryModel queryModel, bool returnDefaultWhenEmpty)
	{
	var col = ExecuteCollection<T>(queryModel);

	return returnDefaultWhenEmpty ? col.SingleOrDefault() : col.Single();
	}

	/** <inheritdoc /> */
	[SuppressMessage("Microsoft.Design", "CA1062:Validate arguments of public methods")]
	public IEnumerable<T> ExecuteCollection<T>(QueryModel queryModel)
	{
	Debug.Assert(queryModel != null);

	var qryData = GetQueryData(queryModel);

	Debug.WriteLine("\nFields Query: {0} \| {1}", qryData.QueryText,
	string.Join(", ", qryData.Parameters.Select(x => x == null ? "null" : x.ToString())));

	var qry = GetFieldsQuery(qryData.QueryText, qryData.Parameters.ToArray());

	var selector = GetResultSelector<T>(queryModel.SelectClause.Selector);

	return _cache.Query(qry, selector);
	}

	/// <summary>
	/// Compiles the query without regard to number or order of arguments.
	/// </summary>
	public Func<object[], IQueryCursor<T>> CompileQuery<T>(QueryModel queryModel)
	{
	Debug.Assert(queryModel != null);

	var qryText = GetQueryData(queryModel).QueryText;
	var selector = GetResultSelector<T>(queryModel.SelectClause.Selector);

	return args => _cache.Query(GetFieldsQuery(qryText, args), selector);
	}

	/// <summary>
	/// Compiles the query.
	/// </summary>
	/// <typeparam name="T">Result type.</typeparam>
	/// <param name="queryModel">The query model.</param>
	/// <param name="queryLambdaModel">The query model generated from lambda body.</param>
	/// <param name="queryLambda">The query lambda.</param>
	/// <returns>Compiled query func.</returns>
	public Func<object[], IQueryCursor<T>> CompileQuery<T>(QueryModel queryModel, QueryModel queryLambdaModel,
	LambdaExpression queryLambda)
	{
	Debug.Assert(queryModel != null);

	// Get model from lambda to map arguments properly.
	var qryData = GetQueryData(queryLambdaModel);

	var qryText = GetQueryData(queryModel).QueryText;
	var qryTextLambda = qryData.QueryText;

	if (qryText != qryTextLambda)
	{
	Debug.WriteLine(qryText);
	Debug.WriteLine(qryTextLambda);

	throw new InvalidOperationException("Error compiling query: entire LINQ expression should be " +
	"specified within lambda passed to Compile method. " +
	"Part of the query can't be outside the Compile method call.");
	}

	var selector = GetResultSelector<T>(queryModel.SelectClause.Selector);

	var qryParams = qryData.Parameters.ToArray();

	// Compiled query is a delegate with query parameters
	// Delegate parameters order and query parameters order may differ

	// Simple case: lambda with no parameters. Only embedded parameters are used.
	if (!queryLambda.Parameters.Any())
	{
	return argsUnused => _cache.Query(GetFieldsQuery(qryText, qryParams), selector);
	}

	// These are in order of usage in query
	var qryOrderArgs = qryParams.OfType<ParameterExpression>().Select(x => x.Name).ToArray();

	// These are in order they come from user
	var userOrderArgs = queryLambda.Parameters.Select(x => x.Name).ToList();

	// Simple case: all query args directly map to the lambda args in the same order
	if (qryOrderArgs.Length == qryParams.Length
	&& qryOrderArgs.SequenceEqual(userOrderArgs))
	{
	return args => _cache.Query(GetFieldsQuery(qryText, args), selector);
	}

	// General case: embedded args and lambda args are mixed; same args can be used multiple times.
	// Produce a mapping that defines where query arguments come from.
	var mapping = qryParams.Select(x =>
	{
	var pe = x as ParameterExpression;

	if (pe != null)
	return userOrderArgs.IndexOf(pe.Name);

	return -1;
	}).ToArray();

	return args => _cache.Query(
	GetFieldsQuery(qryText, MapQueryArgs(args, qryParams, mapping)), selector);
	}

	/// <summary>
	/// Maps the query arguments.
	/// </summary>
	private static object[] MapQueryArgs(object[] userArgs, object[] embeddedArgs, int[] mapping)
	{
	var mappedArgs = new object[embeddedArgs.Length];

	for (var i = 0; i < mappedArgs.Length; i++)
	{
	var map = mapping[i];

	mappedArgs[i] = map < 0 ? embeddedArgs[i] : userArgs[map];
	}

	return mappedArgs;
	}

	/// <summary>
	/// Gets the fields query.
	/// </summary>
	internal SqlFieldsQuery GetFieldsQuery(string text, object[] args)
	{
	return new SqlFieldsQuery(text)
	{
	EnableDistributedJoins = _options.EnableDistributedJoins,
	PageSize = _options.PageSize,
	EnforceJoinOrder = _options.EnforceJoinOrder,
	Timeout = _options.Timeout,
	#pragma warning disable 618
	ReplicatedOnly = _options.ReplicatedOnly,
	#pragma warning restore 618
	Colocated = _options.Colocated,
	Local = _options.Local,
	Arguments = args,
	Lazy = _options.Lazy,
	UpdateBatchSize = _options.UpdateBatchSize,
	Partitions = _options.Partitions
	};
	}

	/// <summary>
	/// Generates <see cref="QueryData"/> from specified <see cref="QueryModel"/>.
	/// </summary>
	public static QueryData GetQueryData(QueryModel queryModel)
	{
	Debug.Assert(queryModel != null);

	return new CacheQueryModelVisitor().GenerateQuery(queryModel);
	}

	/// <summary>
	/// Gets the result selector.
	/// </summary>
	private static Func<IBinaryRawReader, int, T> GetResultSelector<T>(Expression selectorExpression)
	{
	var newExpr = selectorExpression as NewExpression;

	if (newExpr != null)
	return GetCompiledCtor<T>(newExpr.Constructor);

	var entryCtor = GetCacheEntryCtorInfo(typeof(T));

	if (entryCtor != null)
	return GetCompiledCtor<T>(entryCtor);

	if (typeof(T) == typeof(bool))
	return ReadBool<T>;

	return (reader, count) => reader.ReadObject<T>();
	}

	/// <summary>
	/// Reads the bool. Actual data may be bool or int/long.
	/// </summary>
	private static T ReadBool<T>(IBinaryRawReader reader, int count)
	{
	var obj = reader.ReadObject<object>();

	if (obj is bool)
	return (T) obj;

	if (obj is long)
	return TypeCaster<T>.Cast((long) obj != 0);

	if (obj is int)
	return TypeCaster<T>.Cast((int) obj != 0);

	throw new InvalidOperationException("Expected bool, got: " + obj);
	}

	/// <summary>
	/// Gets the cache entry constructor.
	/// </summary>
	private static ConstructorInfo GetCacheEntryCtorInfo(Type entryType)
	{
	if (!entryType.IsGenericType \|\| entryType.GetGenericTypeDefinition() != typeof(ICacheEntry<,>))
	return null;

	var args = entryType.GetGenericArguments();

	var targetType = typeof (CacheEntry<,>).MakeGenericType(args);

	return targetType.GetConstructors().Single();
	}

	/// <summary>
	/// Gets the compiled constructor.
	/// </summary>
	private static Func<IBinaryRawReader, int, T> GetCompiledCtor<T>(ConstructorInfo ctorInfo)
	{
	object result;

	if (CtorCache.TryGetValue(ctorInfo, out result))
	return (Func<IBinaryRawReader, int, T>) result;

	return (Func<IBinaryRawReader, int, T>) CtorCache.GetOrAdd(ctorInfo, x =>
	{
	var innerCtor1 = DelegateConverter.CompileCtor<T>(x, GetCacheEntryCtorInfo);

	return (Func<IBinaryRawReader, int, T>) ((r, c) => innerCtor1(r));
	});
	}
	}
	}