Qstick
3 years ago
parent
4c68645175
commit
68e41f0860
@ -1,389 +1,9 @@
|
||||
using System;
|
||||
using System.Collections.Generic;
|
||||
using System.Data;
|
||||
using System.Linq;
|
||||
using System.Linq.Expressions;
|
||||
using System.Reflection;
|
||||
using System.Text;
|
||||
using Dapper;
|
||||
|
||||
namespace NzbDrone.Core.Datastore
|
||||
{
|
||||
public class WhereBuilder : ExpressionVisitor
|
||||
public abstract class WhereBuilder : ExpressionVisitor
|
||||
{
|
||||
protected StringBuilder _sb;
|
||||
|
||||
private const DbType EnumerableMultiParameter = (DbType)(-1);
|
||||
private readonly string _paramNamePrefix;
|
||||
private readonly bool _requireConcreteValue = false;
|
||||
private int _paramCount = 0;
|
||||
private bool _gotConcreteValue = false;
|
||||
|
||||
public WhereBuilder(Expression filter, bool requireConcreteValue, int seq)
|
||||
{
|
||||
_paramNamePrefix = string.Format("Clause{0}", seq + 1);
|
||||
_requireConcreteValue = requireConcreteValue;
|
||||
_sb = new StringBuilder();
|
||||
|
||||
Parameters = new DynamicParameters();
|
||||
|
||||
if (filter != null)
|
||||
{
|
||||
Visit(filter);
|
||||
}
|
||||
}
|
||||
|
||||
public DynamicParameters Parameters { get; private set; }
|
||||
|
||||
private string AddParameter(object value, DbType? dbType = null)
|
||||
{
|
||||
_gotConcreteValue = true;
|
||||
_paramCount++;
|
||||
var name = _paramNamePrefix + "_P" + _paramCount;
|
||||
Parameters.Add(name, value, dbType);
|
||||
return '@' + name;
|
||||
}
|
||||
|
||||
protected override Expression VisitBinary(BinaryExpression expression)
|
||||
{
|
||||
_sb.Append('(');
|
||||
|
||||
Visit(expression.Left);
|
||||
|
||||
_sb.AppendFormat(" {0} ", Decode(expression));
|
||||
|
||||
Visit(expression.Right);
|
||||
|
||||
_sb.Append(')');
|
||||
|
||||
return expression;
|
||||
}
|
||||
|
||||
protected override Expression VisitMethodCall(MethodCallExpression expression)
|
||||
{
|
||||
var method = expression.Method.Name;
|
||||
|
||||
switch (expression.Method.Name)
|
||||
{
|
||||
case "Contains":
|
||||
ParseContainsExpression(expression);
|
||||
break;
|
||||
|
||||
case "StartsWith":
|
||||
ParseStartsWith(expression);
|
||||
break;
|
||||
|
||||
case "EndsWith":
|
||||
ParseEndsWith(expression);
|
||||
break;
|
||||
|
||||
default:
|
||||
var msg = string.Format("'{0}' expressions are not yet implemented in the where clause expression tree parser.", method);
|
||||
throw new NotImplementedException(msg);
|
||||
}
|
||||
|
||||
return expression;
|
||||
}
|
||||
|
||||
protected override Expression VisitMemberAccess(MemberExpression expression)
|
||||
{
|
||||
var tableName = expression?.Expression?.Type != null ? TableMapping.Mapper.TableNameMapping(expression.Expression.Type) : null;
|
||||
var gotValue = TryGetRightValue(expression, out var value);
|
||||
|
||||
// Only use the SQL condition if the expression didn't resolve to an actual value
|
||||
if (tableName != null && !gotValue)
|
||||
{
|
||||
_sb.Append($"\"{tableName}\".\"{expression.Member.Name}\"");
|
||||
}
|
||||
else
|
||||
{
|
||||
if (value != null)
|
||||
{
|
||||
// string is IEnumerable<Char> but we don't want to pick up that case
|
||||
var type = value.GetType();
|
||||
var typeInfo = type.GetTypeInfo();
|
||||
var isEnumerable =
|
||||
type != typeof(string) && (
|
||||
typeInfo.ImplementedInterfaces.Any(ti => ti.IsGenericType && ti.GetGenericTypeDefinition() == typeof(IEnumerable<>)) ||
|
||||
(typeInfo.IsGenericType && typeInfo.GetGenericTypeDefinition() == typeof(IEnumerable<>)));
|
||||
|
||||
var paramName = isEnumerable ? AddParameter(value, EnumerableMultiParameter) : AddParameter(value);
|
||||
_sb.Append(paramName);
|
||||
}
|
||||
else
|
||||
{
|
||||
_gotConcreteValue = true;
|
||||
_sb.Append("NULL");
|
||||
}
|
||||
}
|
||||
|
||||
return expression;
|
||||
}
|
||||
|
||||
protected override Expression VisitConstant(ConstantExpression expression)
|
||||
{
|
||||
if (expression.Value != null)
|
||||
{
|
||||
var paramName = AddParameter(expression.Value);
|
||||
_sb.Append(paramName);
|
||||
}
|
||||
else
|
||||
{
|
||||
_gotConcreteValue = true;
|
||||
_sb.Append("NULL");
|
||||
}
|
||||
|
||||
return expression;
|
||||
}
|
||||
|
||||
private bool TryGetConstantValue(Expression expression, out object result)
|
||||
{
|
||||
result = null;
|
||||
|
||||
if (expression is ConstantExpression constExp)
|
||||
{
|
||||
result = constExp.Value;
|
||||
return true;
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
private bool TryGetPropertyValue(MemberExpression expression, out object result)
|
||||
{
|
||||
result = null;
|
||||
|
||||
if (expression.Expression is MemberExpression nested)
|
||||
{
|
||||
// Value is passed in as a property on a parent entity
|
||||
var container = (nested.Expression as ConstantExpression)?.Value;
|
||||
|
||||
if (container == null)
|
||||
{
|
||||
return false;
|
||||
}
|
||||
|
||||
var entity = GetFieldValue(container, nested.Member);
|
||||
result = GetFieldValue(entity, expression.Member);
|
||||
return true;
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
private bool TryGetVariableValue(MemberExpression expression, out object result)
|
||||
{
|
||||
result = null;
|
||||
|
||||
// Value is passed in as a variable
|
||||
if (expression.Expression is ConstantExpression nested)
|
||||
{
|
||||
result = GetFieldValue(nested.Value, expression.Member);
|
||||
return true;
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
private bool TryGetRightValue(Expression expression, out object value)
|
||||
{
|
||||
value = null;
|
||||
|
||||
if (TryGetConstantValue(expression, out value))
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
var memberExp = expression as MemberExpression;
|
||||
|
||||
if (TryGetPropertyValue(memberExp, out value))
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
if (TryGetVariableValue(memberExp, out value))
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
private object GetFieldValue(object entity, MemberInfo member)
|
||||
{
|
||||
if (member.MemberType == MemberTypes.Field)
|
||||
{
|
||||
return (member as FieldInfo).GetValue(entity);
|
||||
}
|
||||
|
||||
if (member.MemberType == MemberTypes.Property)
|
||||
{
|
||||
return (member as PropertyInfo).GetValue(entity);
|
||||
}
|
||||
|
||||
throw new ArgumentException(string.Format("WhereBuilder could not get the value for {0}.{1}.", entity.GetType().Name, member.Name));
|
||||
}
|
||||
|
||||
private bool IsNullVariable(Expression expression)
|
||||
{
|
||||
if (expression.NodeType == ExpressionType.Constant &&
|
||||
TryGetConstantValue(expression, out var constResult) &&
|
||||
constResult == null)
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
if (expression.NodeType == ExpressionType.MemberAccess &&
|
||||
expression is MemberExpression member &&
|
||||
((TryGetPropertyValue(member, out var result) && result == null) ||
|
||||
(TryGetVariableValue(member, out result) && result == null)))
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
private string Decode(BinaryExpression expression)
|
||||
{
|
||||
if (IsNullVariable(expression.Right))
|
||||
{
|
||||
switch (expression.NodeType)
|
||||
{
|
||||
case ExpressionType.Equal: return "IS";
|
||||
case ExpressionType.NotEqual: return "IS NOT";
|
||||
}
|
||||
}
|
||||
|
||||
switch (expression.NodeType)
|
||||
{
|
||||
case ExpressionType.AndAlso: return "AND";
|
||||
case ExpressionType.And: return "AND";
|
||||
case ExpressionType.Equal: return "=";
|
||||
case ExpressionType.GreaterThan: return ">";
|
||||
case ExpressionType.GreaterThanOrEqual: return ">=";
|
||||
case ExpressionType.LessThan: return "<";
|
||||
case ExpressionType.LessThanOrEqual: return "<=";
|
||||
case ExpressionType.NotEqual: return "<>";
|
||||
case ExpressionType.OrElse: return "OR";
|
||||
case ExpressionType.Or: return "OR";
|
||||
default: throw new NotSupportedException(string.Format("{0} statement is not supported", expression.NodeType.ToString()));
|
||||
}
|
||||
}
|
||||
|
||||
private void ParseContainsExpression(MethodCallExpression expression)
|
||||
{
|
||||
var list = expression.Object;
|
||||
|
||||
if (list != null && (list.Type == typeof(string)))
|
||||
{
|
||||
ParseStringContains(expression);
|
||||
return;
|
||||
}
|
||||
|
||||
ParseEnumerableContains(expression);
|
||||
}
|
||||
|
||||
private void ParseEnumerableContains(MethodCallExpression body)
|
||||
{
|
||||
// Fish out the list and the item to compare
|
||||
// It's in a different form for arrays and Lists
|
||||
var list = body.Object;
|
||||
Expression item;
|
||||
|
||||
if (list != null)
|
||||
{
|
||||
// Generic collection
|
||||
item = body.Arguments[0];
|
||||
}
|
||||
else
|
||||
{
|
||||
// Static method
|
||||
// Must be Enumerable.Contains(source, item)
|
||||
if (body.Method.DeclaringType != typeof(Enumerable) || body.Arguments.Count != 2)
|
||||
{
|
||||
throw new NotSupportedException("Unexpected form of Enumerable.Contains");
|
||||
}
|
||||
|
||||
list = body.Arguments[0];
|
||||
item = body.Arguments[1];
|
||||
}
|
||||
|
||||
_sb.Append('(');
|
||||
|
||||
Visit(item);
|
||||
|
||||
_sb.Append(" IN ");
|
||||
|
||||
// hardcode the integer list if it exists to bypass parameter limit
|
||||
if (item.Type == typeof(int) && TryGetRightValue(list, out var value))
|
||||
{
|
||||
var items = (IEnumerable<int>)value;
|
||||
_sb.Append('(');
|
||||
_sb.Append(string.Join(", ", items));
|
||||
_sb.Append(')');
|
||||
|
||||
_gotConcreteValue = true;
|
||||
}
|
||||
else
|
||||
{
|
||||
Visit(list);
|
||||
}
|
||||
|
||||
_sb.Append(')');
|
||||
}
|
||||
|
||||
private void ParseStringContains(MethodCallExpression body)
|
||||
{
|
||||
_sb.Append('(');
|
||||
|
||||
Visit(body.Object);
|
||||
|
||||
_sb.Append(" LIKE '%' || ");
|
||||
|
||||
Visit(body.Arguments[0]);
|
||||
|
||||
_sb.Append(" || '%')");
|
||||
}
|
||||
|
||||
private void ParseStartsWith(MethodCallExpression body)
|
||||
{
|
||||
_sb.Append('(');
|
||||
|
||||
Visit(body.Object);
|
||||
|
||||
_sb.Append(" LIKE ");
|
||||
|
||||
Visit(body.Arguments[0]);
|
||||
|
||||
_sb.Append(" || '%')");
|
||||
}
|
||||
|
||||
private void ParseEndsWith(MethodCallExpression body)
|
||||
{
|
||||
_sb.Append('(');
|
||||
|
||||
Visit(body.Object);
|
||||
|
||||
_sb.Append(" LIKE '%' || ");
|
||||
|
||||
Visit(body.Arguments[0]);
|
||||
|
||||
_sb.Append(')');
|
||||
}
|
||||
|
||||
public override string ToString()
|
||||
{
|
||||
var sql = _sb.ToString();
|
||||
|
||||
if (_requireConcreteValue && !_gotConcreteValue)
|
||||
{
|
||||
var e = new InvalidOperationException("WhereBuilder requires a concrete condition");
|
||||
e.Data.Add("sql", sql);
|
||||
throw e;
|
||||
}
|
||||
|
||||
return sql;
|
||||
}
|
||||
public DynamicParameters Parameters { get; protected set; }
|
||||
}
|
||||
}
|
||||
|
||||
@ -0,0 +1,374 @@
|
||||
using System;
|
||||
using System.Collections.Generic;
|
||||
using System.Data;
|
||||
using System.Linq;
|
||||
using System.Linq.Expressions;
|
||||
using System.Reflection;
|
||||
using System.Text;
|
||||
using Dapper;
|
||||
|
||||
namespace NzbDrone.Core.Datastore
|
||||
{
|
||||
public class WhereBuilderPostgres : WhereBuilder
|
||||
{
|
||||
protected StringBuilder _sb;
|
||||
|
||||
private const DbType EnumerableMultiParameter = (DbType)(-1);
|
||||
private readonly string _paramNamePrefix;
|
||||
private readonly bool _requireConcreteValue = false;
|
||||
private int _paramCount = 0;
|
||||
private bool _gotConcreteValue = false;
|
||||
|
||||
public WhereBuilderPostgres(Expression filter, bool requireConcreteValue, int seq)
|
||||
{
|
||||
_paramNamePrefix = string.Format("Clause{0}", seq + 1);
|
||||
_requireConcreteValue = requireConcreteValue;
|
||||
_sb = new StringBuilder();
|
||||
|
||||
Parameters = new DynamicParameters();
|
||||
|
||||
if (filter != null)
|
||||
{
|
||||
Visit(filter);
|
||||
}
|
||||
}
|
||||
|
||||
private string AddParameter(object value, DbType? dbType = null)
|
||||
{
|
||||
_gotConcreteValue = true;
|
||||
_paramCount++;
|
||||
var name = _paramNamePrefix + "_P" + _paramCount;
|
||||
Parameters.Add(name, value, dbType);
|
||||
return '@' + name;
|
||||
}
|
||||
|
||||
protected override Expression VisitBinary(BinaryExpression expression)
|
||||
{
|
||||
_sb.Append('(');
|
||||
|
||||
Visit(expression.Left);
|
||||
|
||||
_sb.AppendFormat(" {0} ", Decode(expression));
|
||||
|
||||
Visit(expression.Right);
|
||||
|
||||
_sb.Append(')');
|
||||
|
||||
return expression;
|
||||
}
|
||||
|
||||
protected override Expression VisitMethodCall(MethodCallExpression expression)
|
||||
{
|
||||
var method = expression.Method.Name;
|
||||
|
||||
switch (expression.Method.Name)
|
||||
{
|
||||
case "Contains":
|
||||
ParseContainsExpression(expression);
|
||||
break;
|
||||
|
||||
case "StartsWith":
|
||||
ParseStartsWith(expression);
|
||||
break;
|
||||
|
||||
case "EndsWith":
|
||||
ParseEndsWith(expression);
|
||||
break;
|
||||
|
||||
default:
|
||||
var msg = string.Format("'{0}' expressions are not yet implemented in the where clause expression tree parser.", method);
|
||||
throw new NotImplementedException(msg);
|
||||
}
|
||||
|
||||
return expression;
|
||||
}
|
||||
|
||||
protected override Expression VisitMemberAccess(MemberExpression expression)
|
||||
{
|
||||
var tableName = expression?.Expression?.Type != null ? TableMapping.Mapper.TableNameMapping(expression.Expression.Type) : null;
|
||||
var gotValue = TryGetRightValue(expression, out var value);
|
||||
|
||||
// Only use the SQL condition if the expression didn't resolve to an actual value
|
||||
if (tableName != null && !gotValue)
|
||||
{
|
||||
_sb.Append($"\"{tableName}\".\"{expression.Member.Name}\"");
|
||||
}
|
||||
else
|
||||
{
|
||||
if (value != null)
|
||||
{
|
||||
// string is IEnumerable<Char> but we don't want to pick up that case
|
||||
var type = value.GetType();
|
||||
var typeInfo = type.GetTypeInfo();
|
||||
var isEnumerable =
|
||||
type != typeof(string) && (
|
||||
typeInfo.ImplementedInterfaces.Any(ti => ti.IsGenericType && ti.GetGenericTypeDefinition() == typeof(IEnumerable<>)) ||
|
||||
(typeInfo.IsGenericType && typeInfo.GetGenericTypeDefinition() == typeof(IEnumerable<>)));
|
||||
|
||||
var paramName = isEnumerable ? AddParameter(value, EnumerableMultiParameter) : AddParameter(value);
|
||||
_sb.Append(paramName);
|
||||
}
|
||||
else
|
||||
{
|
||||
_gotConcreteValue = true;
|
||||
_sb.Append("NULL");
|
||||
}
|
||||
}
|
||||
|
||||
return expression;
|
||||
}
|
||||
|
||||
protected override Expression VisitConstant(ConstantExpression expression)
|
||||
{
|
||||
if (expression.Value != null)
|
||||
{
|
||||
var paramName = AddParameter(expression.Value);
|
||||
_sb.Append(paramName);
|
||||
}
|
||||
else
|
||||
{
|
||||
_gotConcreteValue = true;
|
||||
_sb.Append("NULL");
|
||||
}
|
||||
|
||||
return expression;
|
||||
}
|
||||
|
||||
private bool TryGetConstantValue(Expression expression, out object result)
|
||||
{
|
||||
result = null;
|
||||
|
||||
if (expression is ConstantExpression constExp)
|
||||
{
|
||||
result = constExp.Value;
|
||||
return true;
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
private bool TryGetPropertyValue(MemberExpression expression, out object result)
|
||||
{
|
||||
result = null;
|
||||
|
||||
if (expression.Expression is MemberExpression nested)
|
||||
{
|
||||
// Value is passed in as a property on a parent entity
|
||||
var container = (nested.Expression as ConstantExpression)?.Value;
|
||||
|
||||
if (container == null)
|
||||
{
|
||||
return false;
|
||||
}
|
||||
|
||||
var entity = GetFieldValue(container, nested.Member);
|
||||
result = GetFieldValue(entity, expression.Member);
|
||||
return true;
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
private bool TryGetVariableValue(MemberExpression expression, out object result)
|
||||
{
|
||||
result = null;
|
||||
|
||||
// Value is passed in as a variable
|
||||
if (expression.Expression is ConstantExpression nested)
|
||||
{
|
||||
result = GetFieldValue(nested.Value, expression.Member);
|
||||
return true;
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
private bool TryGetRightValue(Expression expression, out object value)
|
||||
{
|
||||
value = null;
|
||||
|
||||
if (TryGetConstantValue(expression, out value))
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
var memberExp = expression as MemberExpression;
|
||||
|
||||
if (TryGetPropertyValue(memberExp, out value))
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
if (TryGetVariableValue(memberExp, out value))
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
private object GetFieldValue(object entity, MemberInfo member)
|
||||
{
|
||||
if (member.MemberType == MemberTypes.Field)
|
||||
{
|
||||
return (member as FieldInfo).GetValue(entity);
|
||||
}
|
||||
|
||||
if (member.MemberType == MemberTypes.Property)
|
||||
{
|
||||
return (member as PropertyInfo).GetValue(entity);
|
||||
}
|
||||
|
||||
throw new ArgumentException(string.Format("WhereBuilder could not get the value for {0}.{1}.", entity.GetType().Name, member.Name));
|
||||
}
|
||||
|
||||
private bool IsNullVariable(Expression expression)
|
||||
{
|
||||
if (expression.NodeType == ExpressionType.Constant &&
|
||||
TryGetConstantValue(expression, out var constResult) &&
|
||||
constResult == null)
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
if (expression.NodeType == ExpressionType.MemberAccess &&
|
||||
expression is MemberExpression member &&
|
||||
((TryGetPropertyValue(member, out var result) && result == null) ||
|
||||
(TryGetVariableValue(member, out result) && result == null)))
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
private string Decode(BinaryExpression expression)
|
||||
{
|
||||
if (IsNullVariable(expression.Right))
|
||||
{
|
||||
switch (expression.NodeType)
|
||||
{
|
||||
case ExpressionType.Equal: return "IS";
|
||||
case ExpressionType.NotEqual: return "IS NOT";
|
||||
}
|
||||
}
|
||||
|
||||
switch (expression.NodeType)
|
||||
{
|
||||
case ExpressionType.AndAlso: return "AND";
|
||||
case ExpressionType.And: return "AND";
|
||||
case ExpressionType.Equal: return "=";
|
||||
case ExpressionType.GreaterThan: return ">";
|
||||
case ExpressionType.GreaterThanOrEqual: return ">=";
|
||||
case ExpressionType.LessThan: return "<";
|
||||
case ExpressionType.LessThanOrEqual: return "<=";
|
||||
case ExpressionType.NotEqual: return "<>";
|
||||
case ExpressionType.OrElse: return "OR";
|
||||
case ExpressionType.Or: return "OR";
|
||||
default: throw new NotSupportedException(string.Format("{0} statement is not supported", expression.NodeType.ToString()));
|
||||
}
|
||||
}
|
||||
|
||||
private void ParseContainsExpression(MethodCallExpression expression)
|
||||
{
|
||||
var list = expression.Object;
|
||||
|
||||
if (list != null && (list.Type == typeof(string)))
|
||||
{
|
||||
ParseStringContains(expression);
|
||||
return;
|
||||
}
|
||||
|
||||
ParseEnumerableContains(expression);
|
||||
}
|
||||
|
||||
private void ParseEnumerableContains(MethodCallExpression body)
|
||||
{
|
||||
// Fish out the list and the item to compare
|
||||
// It's in a different form for arrays and Lists
|
||||
var list = body.Object;
|
||||
Expression item;
|
||||
|
||||
if (list != null)
|
||||
{
|
||||
// Generic collection
|
||||
item = body.Arguments[0];
|
||||
}
|
||||
else
|
||||
{
|
||||
// Static method
|
||||
// Must be Enumerable.Contains(source, item)
|
||||
if (body.Method.DeclaringType != typeof(Enumerable) || body.Arguments.Count != 2)
|
||||
{
|
||||
throw new NotSupportedException("Unexpected form of Enumerable.Contains");
|
||||
}
|
||||
|
||||
list = body.Arguments[0];
|
||||
item = body.Arguments[1];
|
||||
}
|
||||
|
||||
_sb.Append('(');
|
||||
|
||||
Visit(item);
|
||||
|
||||
_sb.Append(" = ANY (");
|
||||
|
||||
Visit(list);
|
||||
|
||||
_sb.Append("))");
|
||||
}
|
||||
|
||||
private void ParseStringContains(MethodCallExpression body)
|
||||
{
|
||||
_sb.Append('(');
|
||||
|
||||
Visit(body.Object);
|
||||
|
||||
_sb.Append(" LIKE '%' || ");
|
||||
|
||||
Visit(body.Arguments[0]);
|
||||
|
||||
_sb.Append(" || '%')");
|
||||
}
|
||||
|
||||
private void ParseStartsWith(MethodCallExpression body)
|
||||
{
|
||||
_sb.Append('(');
|
||||
|
||||
Visit(body.Object);
|
||||
|
||||
_sb.Append(" LIKE ");
|
||||
|
||||
Visit(body.Arguments[0]);
|
||||
|
||||
_sb.Append(" || '%')");
|
||||
}
|
||||
|
||||
private void ParseEndsWith(MethodCallExpression body)
|
||||
{
|
||||
_sb.Append('(');
|
||||
|
||||
Visit(body.Object);
|
||||
|
||||
_sb.Append(" LIKE '%' || ");
|
||||
|
||||
Visit(body.Arguments[0]);
|
||||
|
||||
_sb.Append(')');
|
||||
}
|
||||
|
||||
public override string ToString()
|
||||
{
|
||||
var sql = _sb.ToString();
|
||||
|
||||
if (_requireConcreteValue && !_gotConcreteValue)
|
||||
{
|
||||
var e = new InvalidOperationException("WhereBuilder requires a concrete condition");
|
||||
e.Data.Add("sql", sql);
|
||||
throw e;
|
||||
}
|
||||
|
||||
return sql;
|
||||
}
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,387 @@
|
||||
using System;
|
||||
using System.Collections.Generic;
|
||||
using System.Data;
|
||||
using System.Linq;
|
||||
using System.Linq.Expressions;
|
||||
using System.Reflection;
|
||||
using System.Text;
|
||||
using Dapper;
|
||||
|
||||
namespace NzbDrone.Core.Datastore
|
||||
{
|
||||
public class WhereBuilderSqlite : WhereBuilder
|
||||
{
|
||||
protected StringBuilder _sb;
|
||||
|
||||
private const DbType EnumerableMultiParameter = (DbType)(-1);
|
||||
private readonly string _paramNamePrefix;
|
||||
private readonly bool _requireConcreteValue = false;
|
||||
private int _paramCount = 0;
|
||||
private bool _gotConcreteValue = false;
|
||||
|
||||
public WhereBuilderSqlite(Expression filter, bool requireConcreteValue, int seq)
|
||||
{
|
||||
_paramNamePrefix = string.Format("Clause{0}", seq + 1);
|
||||
_requireConcreteValue = requireConcreteValue;
|
||||
_sb = new StringBuilder();
|
||||
|
||||
Parameters = new DynamicParameters();
|
||||
|
||||
if (filter != null)
|
||||
{
|
||||
Visit(filter);
|
||||
}
|
||||
}
|
||||
|
||||
private string AddParameter(object value, DbType? dbType = null)
|
||||
{
|
||||
_gotConcreteValue = true;
|
||||
_paramCount++;
|
||||
var name = _paramNamePrefix + "_P" + _paramCount;
|
||||
Parameters.Add(name, value, dbType);
|
||||
return '@' + name;
|
||||
}
|
||||
|
||||
protected override Expression VisitBinary(BinaryExpression expression)
|
||||
{
|
||||
_sb.Append('(');
|
||||
|
||||
Visit(expression.Left);
|
||||
|
||||
_sb.AppendFormat(" {0} ", Decode(expression));
|
||||
|
||||
Visit(expression.Right);
|
||||
|
||||
_sb.Append(')');
|
||||
|
||||
return expression;
|
||||
}
|
||||
|
||||
protected override Expression VisitMethodCall(MethodCallExpression expression)
|
||||
{
|
||||
var method = expression.Method.Name;
|
||||
|
||||
switch (expression.Method.Name)
|
||||
{
|
||||
case "Contains":
|
||||
ParseContainsExpression(expression);
|
||||
break;
|
||||
|
||||
case "StartsWith":
|
||||
ParseStartsWith(expression);
|
||||
break;
|
||||
|
||||
case "EndsWith":
|
||||
ParseEndsWith(expression);
|
||||
break;
|
||||
|
||||
default:
|
||||
var msg = string.Format("'{0}' expressions are not yet implemented in the where clause expression tree parser.", method);
|
||||
throw new NotImplementedException(msg);
|
||||
}
|
||||
|
||||
return expression;
|
||||
}
|
||||
|
||||
protected override Expression VisitMemberAccess(MemberExpression expression)
|
||||
{
|
||||
var tableName = expression?.Expression?.Type != null ? TableMapping.Mapper.TableNameMapping(expression.Expression.Type) : null;
|
||||
var gotValue = TryGetRightValue(expression, out var value);
|
||||
|
||||
// Only use the SQL condition if the expression didn't resolve to an actual value
|
||||
if (tableName != null && !gotValue)
|
||||
{
|
||||
_sb.Append($"\"{tableName}\".\"{expression.Member.Name}\"");
|
||||
}
|
||||
else
|
||||
{
|
||||
if (value != null)
|
||||
{
|
||||
// string is IEnumerable<Char> but we don't want to pick up that case
|
||||
var type = value.GetType();
|
||||
var typeInfo = type.GetTypeInfo();
|
||||
var isEnumerable =
|
||||
type != typeof(string) && (
|
||||
typeInfo.ImplementedInterfaces.Any(ti => ti.IsGenericType && ti.GetGenericTypeDefinition() == typeof(IEnumerable<>)) ||
|
||||
(typeInfo.IsGenericType && typeInfo.GetGenericTypeDefinition() == typeof(IEnumerable<>)));
|
||||
|
||||
var paramName = isEnumerable ? AddParameter(value, EnumerableMultiParameter) : AddParameter(value);
|
||||
_sb.Append(paramName);
|
||||
}
|
||||
else
|
||||
{
|
||||
_gotConcreteValue = true;
|
||||
_sb.Append("NULL");
|
||||
}
|
||||
}
|
||||
|
||||
return expression;
|
||||
}
|
||||
|
||||
protected override Expression VisitConstant(ConstantExpression expression)
|
||||
{
|
||||
if (expression.Value != null)
|
||||
{
|
||||
var paramName = AddParameter(expression.Value);
|
||||
_sb.Append(paramName);
|
||||
}
|
||||
else
|
||||
{
|
||||
_gotConcreteValue = true;
|
||||
_sb.Append("NULL");
|
||||
}
|
||||
|
||||
return expression;
|
||||
}
|
||||
|
||||
private bool TryGetConstantValue(Expression expression, out object result)
|
||||
{
|
||||
result = null;
|
||||
|
||||
if (expression is ConstantExpression constExp)
|
||||
{
|
||||
result = constExp.Value;
|
||||
return true;
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
private bool TryGetPropertyValue(MemberExpression expression, out object result)
|
||||
{
|
||||
result = null;
|
||||
|
||||
if (expression.Expression is MemberExpression nested)
|
||||
{
|
||||
// Value is passed in as a property on a parent entity
|
||||
var container = (nested.Expression as ConstantExpression)?.Value;
|
||||
|
||||
if (container == null)
|
||||
{
|
||||
return false;
|
||||
}
|
||||
|
||||
var entity = GetFieldValue(container, nested.Member);
|
||||
result = GetFieldValue(entity, expression.Member);
|
||||
return true;
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
private bool TryGetVariableValue(MemberExpression expression, out object result)
|
||||
{
|
||||
result = null;
|
||||
|
||||
// Value is passed in as a variable
|
||||
if (expression.Expression is ConstantExpression nested)
|
||||
{
|
||||
result = GetFieldValue(nested.Value, expression.Member);
|
||||
return true;
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
private bool TryGetRightValue(Expression expression, out object value)
|
||||
{
|
||||
value = null;
|
||||
|
||||
if (TryGetConstantValue(expression, out value))
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
var memberExp = expression as MemberExpression;
|
||||
|
||||
if (TryGetPropertyValue(memberExp, out value))
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
if (TryGetVariableValue(memberExp, out value))
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
private object GetFieldValue(object entity, MemberInfo member)
|
||||
{
|
||||
if (member.MemberType == MemberTypes.Field)
|
||||
{
|
||||
return (member as FieldInfo).GetValue(entity);
|
||||
}
|
||||
|
||||
if (member.MemberType == MemberTypes.Property)
|
||||
{
|
||||
return (member as PropertyInfo).GetValue(entity);
|
||||
}
|
||||
|
||||
throw new ArgumentException(string.Format("WhereBuilder could not get the value for {0}.{1}.", entity.GetType().Name, member.Name));
|
||||
}
|
||||
|
||||
private bool IsNullVariable(Expression expression)
|
||||
{
|
||||
if (expression.NodeType == ExpressionType.Constant &&
|
||||
TryGetConstantValue(expression, out var constResult) &&
|
||||
constResult == null)
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
if (expression.NodeType == ExpressionType.MemberAccess &&
|
||||
expression is MemberExpression member &&
|
||||
((TryGetPropertyValue(member, out var result) && result == null) ||
|
||||
(TryGetVariableValue(member, out result) && result == null)))
|
||||
{
|
||||
return true;
|
||||
}
|
||||
|
||||
return false;
|
||||
}
|
||||
|
||||
private string Decode(BinaryExpression expression)
|
||||
{
|
||||
if (IsNullVariable(expression.Right))
|
||||
{
|
||||
switch (expression.NodeType)
|
||||
{
|
||||
case ExpressionType.Equal: return "IS";
|
||||
case ExpressionType.NotEqual: return "IS NOT";
|
||||
}
|
||||
}
|
||||
|
||||
switch (expression.NodeType)
|
||||
{
|
||||
case ExpressionType.AndAlso: return "AND";
|
||||
case ExpressionType.And: return "AND";
|
||||
case ExpressionType.Equal: return "=";
|
||||
case ExpressionType.GreaterThan: return ">";
|
||||
case ExpressionType.GreaterThanOrEqual: return ">=";
|
||||
case ExpressionType.LessThan: return "<";
|
||||
case ExpressionType.LessThanOrEqual: return "<=";
|
||||
case ExpressionType.NotEqual: return "<>";
|
||||
case ExpressionType.OrElse: return "OR";
|
||||
case ExpressionType.Or: return "OR";
|
||||
default: throw new NotSupportedException(string.Format("{0} statement is not supported", expression.NodeType.ToString()));
|
||||
}
|
||||
}
|
||||
|
||||
private void ParseContainsExpression(MethodCallExpression expression)
|
||||
{
|
||||
var list = expression.Object;
|
||||
|
||||
if (list != null && (list.Type == typeof(string)))
|
||||
{
|
||||
ParseStringContains(expression);
|
||||
return;
|
||||
}
|
||||
|
||||
ParseEnumerableContains(expression);
|
||||
}
|
||||
|
||||
private void ParseEnumerableContains(MethodCallExpression body)
|
||||
{
|
||||
// Fish out the list and the item to compare
|
||||
// It's in a different form for arrays and Lists
|
||||
var list = body.Object;
|
||||
Expression item;
|
||||
|
||||
if (list != null)
|
||||
{
|
||||
// Generic collection
|
||||
item = body.Arguments[0];
|
||||
}
|
||||
else
|
||||
{
|
||||
// Static method
|
||||
// Must be Enumerable.Contains(source, item)
|
||||
if (body.Method.DeclaringType != typeof(Enumerable) || body.Arguments.Count != 2)
|
||||
{
|
||||
throw new NotSupportedException("Unexpected form of Enumerable.Contains");
|
||||
}
|
||||
|
||||
list = body.Arguments[0];
|
||||
item = body.Arguments[1];
|
||||
}
|
||||
|
||||
_sb.Append('(');
|
||||
|
||||
Visit(item);
|
||||
|
||||
_sb.Append(" IN ");
|
||||
|
||||
// hardcode the integer list if it exists to bypass parameter limit
|
||||
if (item.Type == typeof(int) && TryGetRightValue(list, out var value))
|
||||
{
|
||||
var items = (IEnumerable<int>)value;
|
||||
_sb.Append('(');
|
||||
_sb.Append(string.Join(", ", items));
|
||||
_sb.Append(')');
|
||||
|
||||
_gotConcreteValue = true;
|
||||
}
|
||||
else
|
||||
{
|
||||
Visit(list);
|
||||
}
|
||||
|
||||
_sb.Append(')');
|
||||
}
|
||||
|
||||
private void ParseStringContains(MethodCallExpression body)
|
||||
{
|
||||
_sb.Append('(');
|
||||
|
||||
Visit(body.Object);
|
||||
|
||||
_sb.Append(" LIKE '%' || ");
|
||||
|
||||
Visit(body.Arguments[0]);
|
||||
|
||||
_sb.Append(" || '%')");
|
||||
}
|
||||
|
||||
private void ParseStartsWith(MethodCallExpression body)
|
||||
{
|
||||
_sb.Append('(');
|
||||
|
||||
Visit(body.Object);
|
||||
|
||||
_sb.Append(" LIKE ");
|
||||
|
||||
Visit(body.Arguments[0]);
|
||||
|
||||
_sb.Append(" || '%')");
|
||||
}
|
||||
|
||||
private void ParseEndsWith(MethodCallExpression body)
|
||||
{
|
||||
_sb.Append('(');
|
||||
|
||||
Visit(body.Object);
|
||||
|
||||
_sb.Append(" LIKE '%' || ");
|
||||
|
||||
Visit(body.Arguments[0]);
|
||||
|
||||
_sb.Append(')');
|
||||
}
|
||||
|
||||
public override string ToString()
|
||||
{
|
||||
var sql = _sb.ToString();
|
||||
|
||||
if (_requireConcreteValue && !_gotConcreteValue)
|
||||
{
|
||||
var e = new InvalidOperationException("WhereBuilder requires a concrete condition");
|
||||
e.Data.Add("sql", sql);
|
||||
throw e;
|
||||
}
|
||||
|
||||
return sql;
|
||||
}
|
||||
}
|
||||
}
|
||||
Loading…
Reference in new issue