Merge pull request #96 from kevindost/feature/filter-on-nulls

Add filtering on null.
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Ashish Patel 2020-10-23 23:39:54 +05:30 committed by GitHub
commit 51b5356ec7
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2 changed files with 61 additions and 14 deletions

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@ -56,6 +56,7 @@ namespace Sieve.Services
where TFilterTerm : IFilterTerm, new() where TFilterTerm : IFilterTerm, new()
where TSortTerm : ISortTerm, new() where TSortTerm : ISortTerm, new()
{ {
private const string nullFilterValue = "null";
private readonly IOptions<SieveOptions> _options; private readonly IOptions<SieveOptions> _options;
private readonly ISieveCustomSortMethods _customSortMethods; private readonly ISieveCustomSortMethods _customSortMethods;
private readonly ISieveCustomFilterMethods _customFilterMethods; private readonly ISieveCustomFilterMethods _customFilterMethods;
@ -179,15 +180,14 @@ namespace Sieve.Services
var (fullPropertyName, property) = GetSieveProperty<TEntity>(false, true, filterTermName); var (fullPropertyName, property) = GetSieveProperty<TEntity>(false, true, filterTermName);
if (property != null) if (property != null)
{ {
var converter = TypeDescriptor.GetConverter(property.PropertyType);
Expression propertyValue = parameter; Expression propertyValue = parameter;
Expression nullCheck = null; Expression nullCheck = null;
var names = fullPropertyName.Split('.');
foreach (var name in fullPropertyName.Split('.')) for (var i = 0; i < names.Length; i++)
{ {
propertyValue = Expression.PropertyOrField(propertyValue, name); propertyValue = Expression.PropertyOrField(propertyValue, names[i]);
if (propertyValue.Type.IsNullable()) if (i != names.Length - 1 && propertyValue.Type.IsNullable())
{ {
nullCheck = GenerateFilterNullCheckExpression(propertyValue, nullCheck); nullCheck = GenerateFilterNullCheckExpression(propertyValue, nullCheck);
} }
@ -195,15 +195,13 @@ namespace Sieve.Services
if (filterTerm.Values == null) continue; if (filterTerm.Values == null) continue;
var converter = TypeDescriptor.GetConverter(property.PropertyType);
foreach (var filterTermValue in filterTerm.Values) foreach (var filterTermValue in filterTerm.Values)
{ {
var isFilterTermValueNull = filterTermValue.ToLower() == nullFilterValue;
dynamic constantVal = converter.CanConvertFrom(typeof(string)) var filterValue = isFilterTermValueNull
? converter.ConvertFrom(filterTermValue) ? Expression.Constant(null, property.PropertyType)
: Convert.ChangeType(filterTermValue, property.PropertyType); : ConvertStringValueToConstantExpression(filterTermValue, property, converter);
Expression filterValue = GetClosureOverConstant(constantVal, property.PropertyType);
if (filterTerm.OperatorIsCaseInsensitive) if (filterTerm.OperatorIsCaseInsensitive)
{ {
@ -223,9 +221,13 @@ namespace Sieve.Services
expression = Expression.Not(expression); expression = Expression.Not(expression);
} }
if (nullCheck != null) var filterValueNullCheck = !isFilterTermValueNull && propertyValue.Type.IsNullable()
? GenerateFilterNullCheckExpression(propertyValue, nullCheck)
: nullCheck;
if (filterValueNullCheck != null)
{ {
expression = Expression.AndAlso(nullCheck, expression); expression = Expression.AndAlso(filterValueNullCheck, expression);
} }
if (innerExpression == null) if (innerExpression == null)
@ -272,6 +274,15 @@ namespace Sieve.Services
: Expression.AndAlso(nullCheckExpression, Expression.NotEqual(propertyValue, Expression.Default(propertyValue.Type))); : Expression.AndAlso(nullCheckExpression, Expression.NotEqual(propertyValue, Expression.Default(propertyValue.Type)));
} }
private Expression ConvertStringValueToConstantExpression(string value, PropertyInfo property, TypeConverter converter)
{
dynamic constantVal = converter.CanConvertFrom(typeof(string))
? converter.ConvertFrom(value)
: Convert.ChangeType(value, property.PropertyType);
return GetClosureOverConstant(constantVal, property.PropertyType);
}
private static Expression GetExpression(TFilterTerm filterTerm, dynamic filterValue, dynamic propertyValue) private static Expression GetExpression(TFilterTerm filterTerm, dynamic filterValue, dynamic propertyValue)
{ {
switch (filterTerm.OperatorParsed) switch (filterTerm.OperatorParsed)

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@ -528,5 +528,41 @@ namespace SieveUnitTests
Assert.AreEqual(sortedPosts[0].Id, 2); Assert.AreEqual(sortedPosts[0].Id, 2);
Assert.AreEqual(sortedPosts[1].Id, 1); Assert.AreEqual(sortedPosts[1].Id, 1);
} }
[TestMethod]
public void FilteringOnNullWorks()
{
var posts = new List<Post>
{
new Post() {
Id = 1,
Title = null,
LikeCount = 0,
IsDraft = false,
CategoryId = null,
TopComment = null,
FeaturedComment = null
},
new Post() {
Id = 2,
Title = null,
LikeCount = 0,
IsDraft = false,
CategoryId = null,
TopComment = null,
FeaturedComment = new Comment { Id = 1, Text = null }
},
}.AsQueryable();
var model = new SieveModel()
{
Filters = "FeaturedComment.Text==null",
};
var result = _processor.Apply(model, posts);
Assert.AreEqual(1, result.Count());
var filteredPosts = result.ToList();
Assert.AreEqual(filteredPosts[0].Id, 2);
}
} }
} }