Ooze.Query 🔎

This package enables usage of Readable Queries on IQueryable<T> instances. This is a concept where you can write actual expression as a string representation for filtering. For example if you have bunch of Posts which have Id and Name columns, you could filter them out via something like Id >= '3' && Name != 'My Post'. This in turn will be translated into the correct expression and applied to your IQueryable instance.

Installation ⚙

First you'll need to install package from Github package repository. In order to do so follow directions on the official github documentation. You'll need to generate Github personal access token and add new nuget source in order to install package from github. More information can be found on the before mentioned page.

Working with Ooze.Query

Supported logical operations for queries are AND (&&) and OR (||). On the other side of things supported value operators are next:

• GreaterThan - >>
• GreaterThanOrEqual ->=
• LessThan - <<
• LessThanOrEqual - <=
• Equal - ==
• NotEqual - !=
• StartsWith - @=
• EndsWith - =@
• Contains - %%

In order for this to work correctly you'll need to add implementation of IQueryFilterProvider<T> which will need to be registered to ServiceCollection. This implementation will contain filter fields which you enable for use in queries. Example implementation can be seen below (based on previous Blog example):

public class BlogQueryFiltersProvider : IOozeQueryFilterProvider<Blog>
{
    public IEnumerable<IQueryFilterDefinition<Blog>> GetFilters()
    {
        return QueryFilters.CreateFor<Blog>()
            .Add(x => x.Id, name: "Id")
            .Add(x => x.Name, name: "Name")
            .Build();
    }
}

//register Ooze.Query to your service collection and add filter provider for your type
services.AddOozeQuery()
    .AddFilterProvider<BlogQueryFiltersProvider>();

After registering required services/dependencies you just need to call Apply method on instance of Ooze Handler. Example can be seen below:

//lets say we have a simple controller action that will filter posts by hardcoded query
//you can always pass that query from outside as this is just an example
[HttpGet]
public async Task<IActionResult> Get(
    [FromServices]IOozeQueryHandler<Post> handler,
    [FromServices]DatabaseContext db)
{
    IQueryable<Post> queryable = db.Set<Post>();
    var sampleLanguageQuery = "Id >> '3' && Name != 'Test'";
    queryable = handler.Apply(queryable, sampleLanguageQuery);
    //this materialized list now contains posts that meet the filter above
    var materialized = queryable.ToListAsync();

    //map this to some DTO before returning
    return Ok(materialized);
}