QueryPack.Criterias 1.0.4

QueryPack.Criterias

Is a simple abstraction layer that allows for the creation and storage of reusable predicates. This layer implements a fluent criteria builder that builds type-safe expression predicates. These predicates can be used to filter and query data from various data sources, that support LINQ

Getting Started

1. Install the package into your project

dotnet add package QueryPack.Criterias

2. Create and configure your criteria builder

class EntitySearchBuilder : GenericCriteriaBuilder<Entity, SearchModel>
{
   public EntitySearchBuilder()
   {
         With(m => e => e.Property.StartsWith(m.Property),
               r => r.When(m => !string.IsNullOrEmpty(m.Property)));
   }
}

3. Add the following line to the Startup Configure method.

 services.AddCriteriaBuilders(typeof(YourType).Assembly);

4. Inject criteria builder into your service and build search criteria

ICriteriaBuilder<Entity, SearchModel> _criteriaBuilder;

Expression<Func<Entity, bool>> criteria = _criteriaBuilder.Build(searchModel);

5. Implement an in-memory search using the UseInMemoryTextSearchBy extension method.

IEnumerable<Entity> entities;

var results = entities.UseInMemoryTextSearchBy(builder => 
      builder.IncludeField(e => e.Property).When(e => !string.IsNullOrEmpty(e.Property)), 
                new SearchEntity
                {
                    TextSearch = "Test String"
                });

6. Add in-memory order using the UseInMemoryOrderBy extension method

IEnumerable<Entity> entities;
var query = new OrderModel
{
       OrderBy = new Dictionary<string, OrderDirection>
       {
            ["fieldA"] = OrderDirection.Asc,
            ["fieldB"] = OrderDirection.Desc
       }
};
var ordered = entities.UseInMemoryOrderBy(query,
                    optionsConfigurer => optionsConfigurer.AddComparerFactory(new EnumNameComparerFactory()));

7. Create a query criteria configuration and inject query visitor

class EntityQueryConfiguration : IQueryConfiguration<Entity, EntityQuery>
{
    public void Configure(IQueryCriteriaBuilder<Entity, EntityQuery> builder)
    {
        builder.AddPredicate(m => e => e.Property.StartsWith(m.SearchProperty),
            r => r.When(m => !string.IsNullOrEmpty(m.SearchProperty)));

        builder.AddOrder(e => new { e.Property, e.PropertyTwo }, builder => builder.From(e => e.OrderBy));
    }
}

var queryModel = new EntityQuery
{
    SearchProperty = "search string",
    OrderBy = new Dictionary<string, OrderDirection>
    {
        ["Property"] = OrderDirection.Asc,
    }
};

IQueryable<Entity> query;

IQueryVisitorBuilder<Entity, EntityQuery> _visitorBuilder;
IQueryVisitor<Entity> visitor = _visitorBuilder.GetVisitor(queryModel);

query = visitor.Visit(query);